Polymyalgia Rheumatica

Inflammatory Disorder MONDO:0019735 Pathograph 13 Show in embeddings browser Inflammatory Rheumatic Diseases

Polymyalgia rheumatica is one of the most common inflammatory rheumatic diseases of people over 50, presenting with neck pain, bilateral shoulder and hip girdle pain, and prominent morning stiffness, together with a systemic acute-phase response. Despite the name, the lesion is not in muscle: imaging and bursal biopsy place it in peri-articular synovial structures, consistently showing bilateral subacromial bursitis, biceps long-head tenosynovitis and trochanteric bursitis. Macrophages and fibroblast-like synoviocytes in these bursae drive an IL-6-centred cytokine loop, in which IL-1, IL-6, IL-17 and TNF-alpha activate synoviocytes that themselves secrete IL-6 and proliferate further. IL-6 accounts for much of what patients actually experience beyond pain — fatigue, sleep disturbance and low mood — through effects on the hypothalamic-pituitary-adrenal axis and on peripheral and central pain pathways. There is no specific diagnostic test, so diagnosis rests on exclusion. Glucocorticoids induce remission in most patients but more than half cannot taper off them, which is the clinical problem that IL-6 receptor blockade with tocilizumab or sarilumab addresses.

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6
Pathophys.
4
Phenotypes
13
Pathograph
1
Genes
3
Medical Actions
1
Trials
8
References
⚙

Pathophysiology

6
Age-Associated Inflammatory Susceptibility
Polymyalgia rheumatica is essentially confined to people aged 50 and over, and is one of the most common inflammatory rheumatic diseases in that age group. Age is therefore not merely an epidemiological association but the permissive condition for the disease, which is why it sits at the head of the causal chain. It shares this age restriction, and much of its immunopathophysiology, with giant cell arteritis and rheumatoid arthritis.
inflammatory response GO:0006954 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased inflammatory response (GO:0006954). GO:0006954 is a biological process from the Gene Ontology. ↑ INCREASED
Downstream
Bursal Macrophage and Synoviocyte Activation
Show evidence (2 references)
PMID:41107118 SUPPORT Human Clinical
"Polymyalgia rheumatica (PMR) is one of the most common inflammatory rheumatic diseases in people aged ≥50 years"
Establishes the restriction of the disease to older adults, the permissive condition this node describes.
PMID:41107118 SUPPORT Human Clinical
"It is closely interlinked with giant cell arteritis (GCA) (potentially considered the GCA-PMR spectrum) and rheumatoid arthritis and shares a common immunopathophysiology with both."
Records the shared immunopathophysiology with GCA and rheumatoid arthritis, which is why this entry relates to, rather than duplicates, the existing giant cell arteritis entry.
Bursal Macrophage and Synoviocyte Activation
Immunohistological study of subacromial bursal biopsies places the cellular lesion in the bursa rather than in muscle. Macrophages and fibroblast-like synoviocytes accumulate there, and proinflammatory cytokines including IL-1, IL-6, IL-17 and TNF-alpha activate the synoviocytes. This is the point at which a systemic age-associated susceptibility becomes a localised, biopsy-visible inflammatory lesion in specific peri-articular structures.
fibroblast-like synoviocyte CL:0002301 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves fibroblast-like synoviocyte, annotated with type B synovial cell (CL:0002301). CL:0002301 is a cell type from the Cell Ontology. macrophage CL:0000235 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves macrophage (CL:0000235). CL:0000235 is a cell type from the Cell Ontology.
inflammatory response GO:0006954 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased inflammatory response (GO:0006954). GO:0006954 is a biological process from the Gene Ontology. ↑ INCREASED
subacromial bursa UBERON:0003668 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in subacromial bursa, annotated with synovial bursa (UBERON:0003668). UBERON:0003668 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
IL-6 Amplification Loop
Show evidence (1 reference)
PMID:41107118 SUPPORT Human Clinical
"Immunohistological studies using biopsies from subacromial bursae have indicated that various cytokines and cells, including macrophages, interleukin-6 (IL-6), and fibroblast-like synoviocytes (FLS), play an integral role in the immunopathophysiology of PMR."
Directly localises the cellular lesion to the subacromial bursa and names the participating cell types on biopsy evidence.
IL-6 Amplification Loop
The cytokine circuit is self-reinforcing rather than linear. Proinflammatory cytokines activate fibroblast-like synoviocytes, which then secrete IL-6, and that IL-6 in turn promotes further synoviocyte proliferation. This feed-forward structure explains why the disease is sustained rather than self-limiting, and why interrupting IL-6 receptor signalling is disproportionately effective compared with blocking any single upstream cytokine.
fibroblast-like synoviocyte CL:0002301 Cell Ontology (CL) Relation: this pathophysiological event involves this cell type This pathophysiological event involves fibroblast-like synoviocyte, annotated with type B synovial cell (CL:0002301). CL:0002301 is a cell type from the Cell Ontology.
positive regulation of interleukin-6 production GO:0032755 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased positive regulation of interleukin-6 production (GO:0032755). GO:0032755 is a biological process from the Gene Ontology. ↑ INCREASED
Downstream
Peri-Articular Bursitis and Tenosynovitis
Systemic Acute-Phase Response
IL-6-Mediated Constitutional Symptoms
Show evidence (2 references)
PMID:41107118 SUPPORT Human Clinical
"Proinflammatory cytokines, including IL-1, IL-6, IL-17, and tumour necrosis factor-alpha, activate FLS which then secrete IL-6 that can further promote FLS proliferation."
Describes the feed-forward IL-6/synoviocyte loop that this node asserts.
PMID:41107118 SUPPORT INDIRECT Human Clinical
"Given the diverse roles of IL-6 in the immunopathophysiology of PMR, targeted molecular therapies such as IL-6 receptor inhibitors offer promising alternatives for disease management"
The therapeutic rationale for IL-6 receptor blockade rests on IL-6 being central to the loop, supporting this node's position in the mechanism.
Peri-Articular Bursitis and Tenosynovitis
The anatomical substrate of the girdle pain, established by ultrasound, MRI and PET rather than by muscle pathology. The consistent findings are bilateral subacromial bursitis, biceps long-head tenosynovitis and trochanteric bursitis, with interspinous bursitis on MRI and PET. This node is why the disease presents as shoulder and hip girdle pain and stiffness despite normal muscle, and it is the direct generator of the musculoskeletal phenotype.
subacromial and trochanteric synovial bursa UBERON:0003668 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in subacromial and trochanteric synovial bursa, annotated with synovial bursa (UBERON:0003668). UBERON:0003668 is an anatomical location from the Uberon multi-species anatomy ontology. shoulder joint UBERON:0016884 Uberon multi-species anatomy ontology (UBERON) Relation: this pathophysiological event occurs in this anatomical location This pathophysiological event occurs in shoulder joint (UBERON:0016884). UBERON:0016884 is an anatomical location from the Uberon multi-species anatomy ontology.
Downstream
Shoulder and Hip Girdle Pain
Morning Stiffness
Show evidence (3 references)
PMID:21565899 SUPPORT Human Clinical
"Bilateral subacromial bursitis, biceps long head tenosynovitis and trochanteric bursitis were particularly consistent findings."
Systematic imaging review establishing the specific peri-articular lesions that constitute the anatomical substrate of the disease.
PMID:28774422 SUPPORT Human Clinical
"Imaging techniques have identified the presence of bursitis in more than half of patients with active disease."
Quantifies how consistently the bursitis substrate is demonstrable in active disease.
PMID:37832573 SUPPORT Human Clinical
"Imaging has helped to identify the pathological substrate of polymyalgia rheumatica"
Confirms that imaging, rather than muscle pathology, defines the pathological substrate.
Systemic Acute-Phase Response
IL-6 released from inflamed bursae drives hepatic acute-phase protein synthesis, so erythrocyte sedimentation rate and C-reactive protein are typically elevated. This is a useful but imperfect disease marker: acute phase reactants rise less during flares in treated patients, and can rise for unrelated reasons, which is part of why assessing disease activity is difficult.
acute-phase response GO:0006953 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased acute-phase response (GO:0006953). GO:0006953 is a biological process from the Gene Ontology. ↑ INCREASED
Downstream
Elevated Acute-Phase Reactants
Show evidence (2 references)
PMID:41107118 SUPPORT Human Clinical
"Activation of synoviocytes in bursae may result in bursitis which can lead to a high concentration of acute-phase reactants and systemic inflammation."
Links bursal synoviocyte activation to the systemic acute-phase response, which is the causal step this node records.
PMID:37832573 SUPPORT Human Clinical
"Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
Confirms elevated acute-phase reactants as a common feature attributable to the inflammatory process.
IL-6-Mediated Constitutional Symptoms
Beyond driving inflammation, IL-6 acts on the hypothalamic-pituitary-adrenal axis and on peripheral and central pain pathways, producing sleep disturbance, mood disturbance, pain amplification and fatigue. This is a separate causal route from the bursal lesion and explains symptoms that pain from bursitis alone would not account for — worth modelling separately because it predicts that IL-6 blockade should improve fatigue and mood, not only joint symptoms.
interleukin-6-mediated signaling pathway GO:0070102 Gene Ontology (GO) Relation: this pathophysiological event involves this biological process This pathophysiological event involves increased interleukin-6-mediated signaling pathway (GO:0070102). GO:0070102 is a biological process from the Gene Ontology. ↑ INCREASED
Downstream
Fatigue
Show evidence (1 reference)
PMID:41107118 SUPPORT Human Clinical
"IL-6 also plays a role in sleep disturbances, mood disorders, pain, and fatigue; it is often seen in PMR, via disruption of the hypothalamic-pituitary-adrenal axis, and actions on the peripheral and central pain pathways."
Directly states the IL-6-mediated route to constitutional symptoms via the HPA axis and pain pathways.
⬡

Pathograph

Use the checkboxes to hide or show graph categories. Hover nodes for evidence and cross-linked metadata.
Pathograph: causal mechanism network for Polymyalgia Rheumatica Interactive directed graph showing how pathophysiology mechanisms, phenotypes, genetic factors and variants, experimental models, environmental triggers, and treatments relate through causal and linked edges.
●

Phenotypes

4
Metabolism 1
Elevated Acute-Phase Reactants FREQUENT Elevated erythrocyte sedimentation rate HP:0003565 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Elevated erythrocyte sedimentation rate (HP:0003565). HP:0003565 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:37832573 SUPPORT Human Clinical
"Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
Establishes elevated acute-phase reactants as a common laboratory feature.
PMID:37832573 SUPPORT INDIRECT Human Clinical
"acute phase reactants are increased less during flares in individuals undergoing treatment or might increase for other reasons"
Qualifies the marker's reliability, supporting the caveat that it is not a dependable measure of disease activity under treatment.
Musculoskeletal 1
Morning Stiffness VERY_FREQUENT Generalized morning stiffness HP:0005197 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Generalized morning stiffness (HP:0005197). HP:0005197 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:41107118 SUPPORT Human Clinical
"characterised by neck pain, bilateral shoulder and hip girdle pain, and morning stiffness"
Records morning stiffness among the defining clinical features.
Constitutional 2
Shoulder and Hip Girdle Pain OBLIGATE Arthralgia HP:0002829 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Arthralgia (HP:0002829), qualified as late onset. HP:0002829 is a phenotype from the Human Phenotype Ontology.
Onset: LATE
Show evidence (2 references)
PMID:41107118 SUPPORT Human Clinical
"characterised by neck pain, bilateral shoulder and hip girdle pain, and morning stiffness"
States girdle pain as a defining feature of the disease.
PMID:37832573 SUPPORT Human Clinical
"Polymyalgia rheumatica is an inflammatory disease producing pain and stiffness, mainly in the shoulders and pelvic girdle, in people older than 50 years."
Defines the distribution of pain and the age group affected.
Fatigue FREQUENT HP:0012378 Human Phenotype Ontology (HP) Relation: this clinical feature is this phenotype This clinical feature is Fatigue (HP:0012378). HP:0012378 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:41107118 SUPPORT Human Clinical
"IL-6 also plays a role in sleep disturbances, mood disorders, pain, and fatigue; it is often seen in PMR"
Records fatigue and related constitutional symptoms as features of PMR attributed to IL-6.
🧬

Genetic Associations

1
HLA-DRB1
Gene: HLA-DRB1 hgnc:4948 HUGO Gene Nomenclature Committee (hgnc) Relation: this disease-associated gene is this gene This disease-associated gene is HLA-DRB1 (hgnc:4948). hgnc:4948 is a gene from the HUGO Gene Nomenclature Committee. relationship_type: MODIFIER
Show evidence (3 references)
PMID:15305244 REFUTE Human Clinical
"The distribution of DRB1 alleles was very similar between PMR patients and controls."
Refutes an HLA-DRB1 susceptibility association for PMR itself, which is why this gene is not recorded as SUSCEPTIBILITY here.
PMID:15305244 SUPPORT Human Clinical
"the development of relapses in patients with PMR was associated with a higher frequency of DRB1*09"
Supports a modifier role affecting relapse rather than disease onset.
PMID:15305244 SUPPORT Human Clinical
"Our data suggest that the HLA-DRB1 alleles associated with susceptibility for developing PMR and GCA are different."
Directly supports the genetic separation of PMR from GCA, reinforcing the lump/split decision recorded in notes.
💊

Medical Actions

3
Glucocorticoid Therapy
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Agent: prednisone NCIT:C770 NCI Thesaurus (NCIT) Relation: this treatment uses this therapeutic agent This treatment uses prednisone (NCIT:C770). NCIT:C770 is a therapeutic agent from the NCI Thesaurus.
Platform: Small molecule
Oral prednisone at 12.5-25 mg daily induces remission in most patients and remains the standard of care, with subsequent tapering. Its limitation is not efficacy but durability and toxicity: relapse on tapering affects 40-60%, more than half of patients never come off, and cumulative exposure causes substantial adverse effects.
Mechanism Target:
Bursal Macrophage and Synoviocyte Activation — Broad, non-specific suppression of the bursal inflammatory infiltrate, which is why response is rapid but relapse follows withdrawal.
Show evidence (1 reference)
PMID:37832573 SUPPORT Human Clinical
"Glucocorticoids at 12·5-25·0 mg prednisone per day are effective in inducing remission in most individuals"
Establishes glucocorticoid efficacy at inducing remission of the inflammatory process.
Target Phenotypes: Arthralgia HP:0002829 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Arthralgia (HP:0002829). HP:0002829 is a phenotype from the Human Phenotype Ontology. Joint stiffness HP:0001387 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Joint stiffness (HP:0001387). HP:0001387 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:28774422 SUPPORT Human Clinical
"A dose of 12·5-25·0 mg prednisolone daily or equivalent leads to rapid improvement of symptoms in most patients with isolated disease."
Independent statement of the effective dose range and the rapidity of response, carrying the dose claim this treatment description makes.
PMID:28774422 SUPPORT Human Clinical
"However, relapses are common when prednisolone is tapered."
Confirms relapse on tapering as the limitation of glucocorticoid monotherapy, which is what motivates the steroid-sparing agents below.
Methotrexate
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Agent: methotrexate CHEBI:44185 Chemical Entities of Biological Interest (CHEBI) Relation: this treatment uses this therapeutic agent This treatment uses methotrexate (CHEBI:44185). CHEBI:44185 is a therapeutic agent from Chemical Entities of Biological Interest.
Platform: Small molecule
The conventional steroid-sparing DMARD, and the option that predates IL-6 blockade. In a randomised placebo-controlled trial added to tapering prednisone, more patients were off prednisone at 76 weeks, fewer had a flare, and the cumulative prednisone dose was lower. Unlike tocilizumab it is not directed at a specific node of the mechanism; it is included because presenting IL-6 blockade as the only steroid-sparing route would misstate the therapeutic landscape, and the EULAR/ACR recommendations cover DMARDs explicitly.
Target Phenotypes: Arthralgia HP:0002829 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Arthralgia (HP:0002829). HP:0002829 is a phenotype from the Human Phenotype Ontology.
Show evidence (3 references)
PMID:15466766 SUPPORT Human Clinical
"Twenty-eight of 32 patients in the methotrexate group and 16 of 30 patients in the placebo group were no longer taking prednisone at 76 weeks (P = 0.003)."
Randomised evidence that adding methotrexate increases the proportion of patients who come off prednisone.
PMID:15466766 SUPPORT Human Clinical
"Prednisone plus methotrexate is associated with shorter prednisone treatment and steroid sparing."
Trial conclusion establishing the steroid-sparing effect.
PMID:28774422 SUPPORT Human Clinical
"Methotrexate might be used in patients who relapse."
Places methotrexate in the treatment pathway for relapsing disease.
IL-6 Receptor Blockade
Action: PharmacotherapyNCI Thesaurus (NCIT) Relation: this treatment is this clinical intervention This treatment is Pharmacotherapy (NCIT:C15986). NCIT:C15986 is a clinical intervention from the NCI Thesaurus. NCIT:C15986
Agent: tocilizumab NCIT:C84217 NCI Thesaurus (NCIT) Relation: this treatment uses this therapeutic agent This treatment uses tocilizumab (NCIT:C84217). NCIT:C84217 is a therapeutic agent from the NCI Thesaurus.
Platform: Monoclonal antibody
Tocilizumab, an IL-6 receptor inhibitor, targets the amplification loop directly rather than suppressing inflammation broadly. In new-onset disease with rapid steroid tapering it tripled the rate of glucocorticoid-free remission, delayed relapse and lowered cumulative steroid dose. Sarilumab has also shown efficacy. This is the mechanistically motivated therapy: it predicts, and delivers, steroid sparing rather than merely additional anti-inflammatory effect.
Mechanism Target:
IL-6 Amplification Loop — Blocking the IL-6 receptor interrupts the feed-forward loop in which synoviocyte-derived IL-6 drives further synoviocyte proliferation.
Show evidence (1 reference)
PMID:35210264 SUPPORT Human Clinical
"Glucocorticoid-free remission at week 16 was achieved in 12 out of 19 patients on tocilizumab (63.2%) and 2 out of 17 patients receiving placebo (11.8%, p=0.002)"
Randomised evidence that IL-6 receptor blockade induces glucocorticoid-free remission, supporting the IL-6 loop as the operative mechanism.
Target Phenotypes: Arthralgia HP:0002829 Human Phenotype Ontology (HP) Relation: this treatment targets this phenotype This treatment targets Arthralgia (HP:0002829). HP:0002829 is a phenotype from the Human Phenotype Ontology.
Show evidence (2 references)
PMID:35210264 SUPPORT Human Clinical
"In patients with new onset polymyalgia rheumatica undergoing rapid glucocorticoid tapering, tocilizumab was superior to placebo regarding sustained glucocorticoid-free remission, time to relapse and cumulative glucocorticoid dose."
Trial conclusion establishing tocilizumab's steroid-sparing benefit across three endpoints.
PMID:37832573 SUPPORT Human Clinical
"tocilizumab and sarilumab have shown efficacy in randomised controlled trials and additional targeted therapies are emerging"
Confirms randomised-trial efficacy for both IL-6 receptor inhibitors used in this disease.
🔬

Biochemical Markers

2
Elevated ESR (Elevated)
Context: The principal laboratory handle in PMR and part of every classification criterion set, but an imperfect activity marker: it rises less during flares in treated patients and can rise for unrelated reasons in this age group.
Show evidence (2 references)
PMID:28774422 SUPPORT Human Clinical
"Increases in acute phase reactants are typical of polymyalgia rheumatica."
Establishes raised acute-phase reactants as typical of the disease.
PMID:37832573 SUPPORT Human Clinical
"acute phase reactants are increased less during flares in individuals undergoing treatment or might increase for other reasons"
Records the limitation that makes this a poor activity marker under treatment.
Elevated CRP (Elevated)
Context: Rises with ESR as part of the IL-6-driven acute-phase response, and is the marker adjusted for in the methotrexate trial's multivariate analysis.
Show evidence (1 reference)
PMID:37832573 SUPPORT Human Clinical
"Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
Establishes the acute-phase response, of which CRP is a component, as a common feature.
🔬

Diagnosis

1
Diagnosis of exclusion
There is no specific diagnostic test. Diagnosis requires excluding other conditions presenting similarly, with imaging used to support the clinical diagnosis and to detect coexistent giant cell arteritis. Assessing disease activity is separately difficult, because pain from common comorbidities such as osteoarthritis and tendinopathy returns as glucocorticoids are reduced and can be mistaken for relapse.
Show evidence (2 references)
PMID:37832573 SUPPORT Human Clinical
"Since there are no specific diagnostic tests, diagnosis requires the exclusion of other diseases with similar presentations."
Establishes the exclusionary basis of diagnosis.
PMID:37832573 SUPPORT Human Clinical
"it is increasingly used to support clinical diagnosis or to detect coexistent giant cell arteritis"
Records the role of imaging in supporting diagnosis and in detecting coexistent giant cell arteritis.
📈

Progression

1
Relapse on glucocorticoid tapering
Glucocorticoids induce remission in most patients, but relapse on tapering is the rule rather than the exception, and more than half never taper off successfully. This is the central clinical problem of the disease and the rationale for steroid-sparing therapy.
Show evidence (1 reference)
PMID:37832573 SUPPORT Human Clinical
"when tapered, relapses occur in 40-60% of those affected and side-effects are common"
Quantifies the relapse rate on tapering, defining this phase of the disease course.
📊

Prevalence

1
Adults aged 50 and over
Unknown Common
No numeric rate is recorded because the cited sources give none. They place the disease qualitatively among the most common inflammatory rheumatic diseases of this age group -- one calls it the second most common -- and it is essentially confined to people over 50, so the population here is the at-risk group rather than the general population. measure_type is UNKNOWN rather than a guess at point prevalence versus incidence.
Show evidence (2 references)
PMID:41107118 SUPPORT Human Clinical
"Polymyalgia rheumatica (PMR) is one of the most common inflammatory rheumatic diseases in people aged ≥50 years"
Places the disease qualitatively among the most common inflammatory rheumatic diseases of this age group.
PMID:35210264 SUPPORT Human Clinical
"Polymyalgia rheumatica is the second most common inflammatory rheumatic disease of people >50 years."
Gives a more specific qualitative ranking within the same age group.
⚖️

Clinical Burden

Moderate
An unusual burden profile: the disease does not clearly shorten life or damage organs, but materially degrades quality of life, and much of the long-term harm comes from prolonged glucocorticoid exposure rather than from the disease itself.
Show evidence (3 references)
PMID:37832573 SUPPORT Human Clinical
"Although polymyalgia rheumatica does not clearly impair survival or organ function, it can have a detrimental effect on quality of life."
States the dissociation between preserved survival and impaired quality of life that defines the burden of this disease.
PMID:28774422 SUPPORT Human Clinical
"Most population-based studies indicate that mortality is not increased in patients with isolated disease."
Independent population-level confirmation that isolated PMR does not increase mortality.
PMID:41107118 SUPPORT Human Clinical
">50% of patients cannot successfully taper GCs, and long-term treatment is associated with considerable GC-related adverse events"
Quantifies the treatment-derived component of the burden, which is the main driver of long-term harm.
🔬

Clinical Trials

1
NCT03263715 PHASE_II COMPLETED
PMR-SPARE: double-blind, multi-centre phase 2/3 trial of subcutaneous tocilizumab versus placebo in 36 patients with new-onset polymyalgia rheumatica undergoing rapid prednisone tapering.
Target Phenotypes: Arthralgia HP:0002829 Human Phenotype Ontology (HP) Relation: this clinical trial targets this phenotype This clinical trial targets Arthralgia (HP:0002829). HP:0002829 is a phenotype from the Human Phenotype Ontology.
Show evidence (1 reference)
PMID:35210264 SUPPORT Human Clinical
"we randomly assigned 36 patients with new onset polymyalgia rheumatica from three centres to receive subcutaneous tocilizumab (162 mg per week) or placebo for 16 weeks"
Describes the trial design and randomisation reported for this registered study.
{ }

Source YAML

click to show 
name: Polymyalgia Rheumatica
creation_date: "2026-09-04T03:05:00Z"
category: Inflammatory Disorder
description: >-
  Polymyalgia rheumatica is one of the most common inflammatory rheumatic
  diseases of people over 50, presenting with neck pain, bilateral shoulder and
  hip girdle pain, and prominent morning stiffness, together with a systemic
  acute-phase response. Despite the name, the lesion is not in muscle: imaging
  and bursal biopsy place it in peri-articular synovial structures, consistently
  showing bilateral subacromial bursitis, biceps long-head tenosynovitis and
  trochanteric bursitis. Macrophages and fibroblast-like synoviocytes in these
  bursae drive an IL-6-centred cytokine loop, in which IL-1, IL-6, IL-17 and
  TNF-alpha activate synoviocytes that themselves secrete IL-6 and proliferate
  further. IL-6 accounts for much of what patients actually experience beyond
  pain — fatigue, sleep disturbance and low mood — through effects on the
  hypothalamic-pituitary-adrenal axis and on peripheral and central pain
  pathways. There is no specific diagnostic test, so diagnosis rests on
  exclusion. Glucocorticoids induce remission in most patients but more than half
  cannot taper off them, which is the clinical problem that IL-6 receptor
  blockade with tocilizumab or sarilumab addresses.
disease_term:
  preferred_term: polymyalgia rheumatica
  term:
    id: MONDO:0019735
    label: polymyalgia rheumatica
synonyms:
- PMR
- rhizomelic pseudopolyarthritis
parents:
- Inflammatory Rheumatic Diseases
notes: >-
  Curated as a Disease in its own right rather than as part of
  Giant_Cell_Arteritis, which is already curated. The two are closely
  interlinked — some authors treat them as a single GCA-PMR spectrum, they share
  immunopathophysiology, and both respond to IL-6 receptor blockade — but they
  are not the same entry. PMR occurs far more often in isolation, its lesion is
  peri-articular bursitis and synovitis rather than large-vessel vasculitis, and
  it carries none of the vision-loss risk that makes GCA an ophthalmic emergency.
  The existing Giant_Cell_Arteritis entry already mentions polymyalgia rheumatica
  as an associated feature; those mentions are correct and were left alone. A
  comorbidity record is probably the right place to express the overlap
  quantitatively, and is not attempted here.

  The name is a historical misnomer worth flagging for anyone curating from it:
  "myalgia" implies muscle disease, but muscle histology and enzymes are normal
  and the imaging substrate is peri-articular. Do not bind muscle-pathology
  terms to the pathophysiology nodes on the strength of the disease name.
references:
- reference: PMID:37832573
  title: "Polymyalgia rheumatica."
- reference: PMID:41107118
  title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
- reference: PMID:21565899
  title: "Imaging of polymyalgia rheumatica: indications on its pathogenesis, diagnosis and prognosis."
- reference: PMID:35210264
  title: "Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial."
- reference: PMID:26359488
  title: "2015 Recommendations for the management of polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative."
- reference: PMID:15466766
  title: "Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial."
- reference: PMID:15305244
  title: "HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: influence on clinical subgroups and prognosis."
- reference: PMID:28774422
  title: "Polymyalgia rheumatica."
pathophysiology:
- name: Age-Associated Inflammatory Susceptibility
  biological_scale: ORGANISM
  description: >-
    Polymyalgia rheumatica is essentially confined to people aged 50 and over,
    and is one of the most common inflammatory rheumatic diseases in that age
    group. Age is therefore not merely an epidemiological association but the
    permissive condition for the disease, which is why it sits at the head of the
    causal chain. It shares this age restriction, and much of its
    immunopathophysiology, with giant cell arteritis and rheumatoid arthritis.
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
    modifier: INCREASED
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Polymyalgia rheumatica (PMR) is one of the most common inflammatory rheumatic diseases in people aged ≥50 years"
    explanation: >-
      Establishes the restriction of the disease to older adults, the permissive
      condition this node describes.
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "It is closely interlinked with giant cell arteritis (GCA) (potentially considered the GCA-PMR spectrum) and rheumatoid arthritis and shares a common immunopathophysiology with both."
    explanation: >-
      Records the shared immunopathophysiology with GCA and rheumatoid arthritis,
      which is why this entry relates to, rather than duplicates, the existing
      giant cell arteritis entry.
  downstream:
  - target: Bursal Macrophage and Synoviocyte Activation
    causal_link_type: INDIRECT_UNKNOWN_INTERMEDIATES
- name: Bursal Macrophage and Synoviocyte Activation
  biological_scale: CELLULAR
  description: >-
    Immunohistological study of subacromial bursal biopsies places the cellular
    lesion in the bursa rather than in muscle. Macrophages and fibroblast-like
    synoviocytes accumulate there, and proinflammatory cytokines including IL-1,
    IL-6, IL-17 and TNF-alpha activate the synoviocytes. This is the point at
    which a systemic age-associated susceptibility becomes a localised,
    biopsy-visible inflammatory lesion in specific peri-articular structures.
  cell_types:
  - preferred_term: fibroblast-like synoviocyte
    term:
      id: CL:0002301
      label: type B synovial cell
  - preferred_term: macrophage
    term:
      id: CL:0000235
      label: macrophage
  locations:
  - preferred_term: subacromial bursa
    term:
      id: UBERON:0003668
      label: synovial bursa
  biological_processes:
  - preferred_term: inflammatory response
    term:
      id: GO:0006954
      label: inflammatory response
    modifier: INCREASED
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Immunohistological studies using biopsies from subacromial bursae have indicated that various cytokines and cells, including macrophages, interleukin-6 (IL-6), and fibroblast-like synoviocytes (FLS), play an integral role in the immunopathophysiology of PMR."
    explanation: >-
      Directly localises the cellular lesion to the subacromial bursa and names
      the participating cell types on biopsy evidence.
  downstream:
  - target: IL-6 Amplification Loop
    causal_link_type: DIRECT
- name: IL-6 Amplification Loop
  biological_scale: MOLECULAR
  description: >-
    The cytokine circuit is self-reinforcing rather than linear. Proinflammatory
    cytokines activate fibroblast-like synoviocytes, which then secrete IL-6,
    and that IL-6 in turn promotes further synoviocyte proliferation. This
    feed-forward structure explains why the disease is sustained rather than
    self-limiting, and why interrupting IL-6 receptor signalling is
    disproportionately effective compared with blocking any single upstream
    cytokine.
  cell_types:
  - preferred_term: fibroblast-like synoviocyte
    term:
      id: CL:0002301
      label: type B synovial cell
  biological_processes:
  - preferred_term: positive regulation of interleukin-6 production
    term:
      id: GO:0032755
      label: positive regulation of interleukin-6 production
    modifier: INCREASED
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Proinflammatory cytokines, including IL-1, IL-6, IL-17, and tumour necrosis factor-alpha, activate FLS which then secrete IL-6 that can further promote FLS proliferation."
    explanation: >-
      Describes the feed-forward IL-6/synoviocyte loop that this node asserts.
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Given the diverse roles of IL-6 in the immunopathophysiology of PMR, targeted molecular therapies such as IL-6 receptor inhibitors offer promising alternatives for disease management"
    explanation: >-
      The therapeutic rationale for IL-6 receptor blockade rests on IL-6 being
      central to the loop, supporting this node's position in the mechanism.
    directness: INDIRECT
  downstream:
  - target: Peri-Articular Bursitis and Tenosynovitis
    causal_link_type: DIRECT
  - target: Systemic Acute-Phase Response
    causal_link_type: DIRECT
  - target: IL-6-Mediated Constitutional Symptoms
    causal_link_type: DIRECT
- name: Peri-Articular Bursitis and Tenosynovitis
  biological_scale: TISSUE
  description: >-
    The anatomical substrate of the girdle pain, established by ultrasound, MRI
    and PET rather than by muscle pathology. The consistent findings are
    bilateral subacromial bursitis, biceps long-head tenosynovitis and
    trochanteric bursitis, with interspinous bursitis on MRI and PET. This node
    is why the disease presents as shoulder and hip girdle pain and stiffness
    despite normal muscle, and it is the direct generator of the musculoskeletal
    phenotype.
  locations:
  - preferred_term: subacromial and trochanteric synovial bursa
    term:
      id: UBERON:0003668
      label: synovial bursa
  - preferred_term: shoulder joint
    term:
      id: UBERON:0016884
      label: shoulder joint
  evidence:
  - reference: PMID:21565899
    reference_title: "Imaging of polymyalgia rheumatica: indications on its pathogenesis, diagnosis and prognosis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Bilateral subacromial bursitis, biceps long head tenosynovitis and trochanteric bursitis were particularly consistent findings."
    explanation: >-
      Systematic imaging review establishing the specific peri-articular lesions
      that constitute the anatomical substrate of the disease.
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Imaging techniques have identified the presence of bursitis in more than half of patients with active disease."
    explanation: >-
      Quantifies how consistently the bursitis substrate is demonstrable in
      active disease.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Imaging has helped to identify the pathological substrate of polymyalgia rheumatica"
    explanation: >-
      Confirms that imaging, rather than muscle pathology, defines the
      pathological substrate.
  downstream:
  - target: Shoulder and Hip Girdle Pain
    causal_link_type: DIRECT
  - target: Morning Stiffness
    causal_link_type: DIRECT
- name: Systemic Acute-Phase Response
  biological_scale: ORGANISM
  description: >-
    IL-6 released from inflamed bursae drives hepatic acute-phase protein
    synthesis, so erythrocyte sedimentation rate and C-reactive protein are
    typically elevated. This is a useful but imperfect disease marker: acute
    phase reactants rise less during flares in treated patients, and can rise for
    unrelated reasons, which is part of why assessing disease activity is
    difficult.
  biological_processes:
  - preferred_term: acute-phase response
    term:
      id: GO:0006953
      label: acute-phase response
    modifier: INCREASED
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Activation of synoviocytes in bursae may result in bursitis which can lead to a high concentration of acute-phase reactants and systemic inflammation."
    explanation: >-
      Links bursal synoviocyte activation to the systemic acute-phase response,
      which is the causal step this node records.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
    explanation: >-
      Confirms elevated acute-phase reactants as a common feature attributable
      to the inflammatory process.
  downstream:
  - target: Elevated Acute-Phase Reactants
    causal_link_type: DIRECT
- name: IL-6-Mediated Constitutional Symptoms
  biological_scale: ORGANISM
  description: >-
    Beyond driving inflammation, IL-6 acts on the hypothalamic-pituitary-adrenal
    axis and on peripheral and central pain pathways, producing sleep
    disturbance, mood disturbance, pain amplification and fatigue. This is a
    separate causal route from the bursal lesion and explains symptoms that pain
    from bursitis alone would not account for — worth modelling separately
    because it predicts that IL-6 blockade should improve fatigue and mood, not
    only joint symptoms.
  biological_processes:
  - preferred_term: interleukin-6-mediated signaling pathway
    term:
      id: GO:0070102
      label: interleukin-6-mediated signaling pathway
    modifier: INCREASED
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "IL-6 also plays a role in sleep disturbances, mood disorders, pain, and fatigue; it is often seen in PMR, via disruption of the hypothalamic-pituitary-adrenal axis, and actions on the peripheral and central pain pathways."
    explanation: >-
      Directly states the IL-6-mediated route to constitutional symptoms via the
      HPA axis and pain pathways.
  downstream:
  - target: Fatigue
    causal_link_type: DIRECT
phenotypes:
- category: Phenotypic
  name: Shoulder and Hip Girdle Pain
  description: >-
    Bilateral aching pain of the shoulder and pelvic girdles with neck
    involvement, the presenting complaint in nearly all patients.
  phenotype_term:
    preferred_term: Arthralgia
    term:
      id: HP:0002829
      label: Arthralgia
    onset:
      onset_category: LATE
  frequency: OBLIGATE
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "characterised by neck pain, bilateral shoulder and hip girdle pain, and morning stiffness"
    explanation: >-
      States girdle pain as a defining feature of the disease.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Polymyalgia rheumatica is an inflammatory disease producing pain and stiffness, mainly in the shoulders and pelvic girdle, in people older than 50 years."
    explanation: >-
      Defines the distribution of pain and the age group affected.
- category: Phenotypic
  name: Morning Stiffness
  description: >-
    Prolonged stiffness of the shoulder and hip girdles on waking, characteristic
    of inflammatory rather than degenerative joint disease.
  phenotype_term:
    preferred_term: Generalized morning stiffness
    term:
      id: HP:0005197
      label: Generalized morning stiffness
  frequency: VERY_FREQUENT
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "characterised by neck pain, bilateral shoulder and hip girdle pain, and morning stiffness"
    explanation: >-
      Records morning stiffness among the defining clinical features.
- category: Phenotypic
  name: Elevated Acute-Phase Reactants
  description: >-
    Raised erythrocyte sedimentation rate and C-reactive protein reflecting
    IL-6-driven hepatic acute-phase protein synthesis. Common but not universal,
    and less reliable as a flare marker in treated patients.
  phenotype_term:
    preferred_term: Elevated erythrocyte sedimentation rate
    term:
      id: HP:0003565
      label: Elevated erythrocyte sedimentation rate
  frequency: FREQUENT
  evidence:
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
    explanation: >-
      Establishes elevated acute-phase reactants as a common laboratory feature.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "acute phase reactants are increased less during flares in individuals undergoing treatment or might increase for other reasons"
    explanation: >-
      Qualifies the marker's reliability, supporting the caveat that it is not a
      dependable measure of disease activity under treatment.
    directness: INDIRECT
- category: Phenotypic
  name: Fatigue
  description: >-
    Fatigue, disturbed sleep and low mood, attributable to IL-6 effects on the
    HPA axis and central pain pathways rather than to joint inflammation alone.
  phenotype_term:
    preferred_term: Fatigue
    term:
      id: HP:0012378
      label: Fatigue
  frequency: FREQUENT
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "IL-6 also plays a role in sleep disturbances, mood disorders, pain, and fatigue; it is often seen in PMR"
    explanation: >-
      Records fatigue and related constitutional symptoms as features of PMR
      attributed to IL-6.
prevalence:
- population: Adults aged 50 and over
  measure_type: UNKNOWN
  prevalence_class: COMMON
  notes: >-
    No numeric rate is recorded because the cited sources give none. They place
    the disease qualitatively among the most common inflammatory rheumatic
    diseases of this age group -- one calls it the second most common -- and it
    is essentially confined to people over 50, so the population here is the
    at-risk group rather than the general population. measure_type is UNKNOWN
    rather than a guess at point prevalence versus incidence.
  evidence:
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Polymyalgia rheumatica (PMR) is one of the most common inflammatory rheumatic diseases in people aged ≥50 years"
    explanation: >-
      Places the disease qualitatively among the most common inflammatory
      rheumatic diseases of this age group.
  - reference: PMID:35210264
    reference_title: "Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Polymyalgia rheumatica is the second most common inflammatory rheumatic disease of people >50 years."
    explanation: >-
      Gives a more specific qualitative ranking within the same age group.

genetic:
- name: HLA-DRB1
  gene_term:
    preferred_term: HLA-DRB1
    term:
      id: hgnc:4948
      label: HLA-DRB1
  relationship_type: MODIFIER
  notes: >-
    Recorded as a MODIFIER, not a susceptibility locus, and that is the point of
    this block. It would be easy to carry HLA-DRB1 across from Giant_Cell_
    Arteritis, which does have susceptibility alleles, but the PMR data do not
    support it: in a Spanish cohort the DRB1 allele distribution in PMR was very
    similar to controls, while DRB1*0401 and *0404 were overrepresented in GCA,
    and the authors conclude the susceptibility alleles for the two diseases are
    different. What DRB1 does appear to do in PMR is predict relapse, with
    DRB1*09 more frequent in relapsing patients.

    This is a second, independent line of evidence for the lump/split call made
    in notes: PMR and GCA do not share their HLA associations.
  evidence:
  - reference: PMID:15305244
    reference_title: "HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: influence on clinical subgroups and prognosis."
    supports: REFUTE
    evidence_source: HUMAN_CLINICAL
    snippet: "The distribution of DRB1 alleles was very similar between PMR patients and controls."
    explanation: >-
      Refutes an HLA-DRB1 susceptibility association for PMR itself, which is
      why this gene is not recorded as SUSCEPTIBILITY here.
  - reference: PMID:15305244
    reference_title: "HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: influence on clinical subgroups and prognosis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "the development of relapses in patients with PMR was associated with a higher frequency of DRB1*09"
    explanation: >-
      Supports a modifier role affecting relapse rather than disease onset.
  - reference: PMID:15305244
    reference_title: "HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: influence on clinical subgroups and prognosis."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Our data suggest that the HLA-DRB1 alleles associated with susceptibility for developing PMR and GCA are different."
    explanation: >-
      Directly supports the genetic separation of PMR from GCA, reinforcing the
      lump/split decision recorded in notes.
biochemical:
- name: Elevated ESR
  presence: Elevated
  context: >-
    The principal laboratory handle in PMR and part of every classification
    criterion set, but an imperfect activity marker: it rises less during flares
    in treated patients and can rise for unrelated reasons in this age group.
  evidence:
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Increases in acute phase reactants are typical of polymyalgia rheumatica."
    explanation: >-
      Establishes raised acute-phase reactants as typical of the disease.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "acute phase reactants are increased less during flares in individuals undergoing treatment or might increase for other reasons"
    explanation: >-
      Records the limitation that makes this a poor activity marker under
      treatment.
- name: Elevated CRP
  presence: Elevated
  context: >-
    Rises with ESR as part of the IL-6-driven acute-phase response, and is the
    marker adjusted for in the methotrexate trial's multivariate analysis.
  evidence:
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Elevation of acute phase reactants is common due to the inflammatory nature of the disease."
    explanation: >-
      Establishes the acute-phase response, of which CRP is a component, as a
      common feature.

clinical_burden:
  burden_level: MODERATE
  rationale: >-
    An unusual burden profile: the disease does not clearly shorten life or
    damage organs, but materially degrades quality of life, and much of the
    long-term harm comes from prolonged glucocorticoid exposure rather than from
    the disease itself.
  evidence:
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Although polymyalgia rheumatica does not clearly impair survival or organ function, it can have a detrimental effect on quality of life."
    explanation: >-
      States the dissociation between preserved survival and impaired quality of
      life that defines the burden of this disease.
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Most population-based studies indicate that mortality is not increased in patients with isolated disease."
    explanation: >-
      Independent population-level confirmation that isolated PMR does not
      increase mortality.
  - reference: PMID:41107118
    reference_title: "Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: ">50% of patients cannot successfully taper GCs, and long-term treatment is associated with considerable GC-related adverse events"
    explanation: >-
      Quantifies the treatment-derived component of the burden, which is the
      main driver of long-term harm.
progression:
- phase: Relapse on glucocorticoid tapering
  notes: >-
    Glucocorticoids induce remission in most patients, but relapse on tapering is
    the rule rather than the exception, and more than half never taper off
    successfully. This is the central clinical problem of the disease and the
    rationale for steroid-sparing therapy.
  evidence:
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "when tapered, relapses occur in 40-60% of those affected and side-effects are common"
    explanation: >-
      Quantifies the relapse rate on tapering, defining this phase of the
      disease course.
diagnosis:
- name: Diagnosis of exclusion
  description: >-
    There is no specific diagnostic test. Diagnosis requires excluding other
    conditions presenting similarly, with imaging used to support the clinical
    diagnosis and to detect coexistent giant cell arteritis. Assessing disease
    activity is separately difficult, because pain from common comorbidities such
    as osteoarthritis and tendinopathy returns as glucocorticoids are reduced and
    can be mistaken for relapse.
  evidence:
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Since there are no specific diagnostic tests, diagnosis requires the exclusion of other diseases with similar presentations."
    explanation: >-
      Establishes the exclusionary basis of diagnosis.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "it is increasingly used to support clinical diagnosis or to detect coexistent giant cell arteritis"
    explanation: >-
      Records the role of imaging in supporting diagnosis and in detecting
      coexistent giant cell arteritis.
treatments:
- name: Glucocorticoid Therapy
  description: >-
    Oral prednisone at 12.5-25 mg daily induces remission in most patients and
    remains the standard of care, with subsequent tapering. Its limitation is not
    efficacy but durability and toxicity: relapse on tapering affects 40-60%,
    more than half of patients never come off, and cumulative exposure causes
    substantial adverse effects.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: prednisone
      term:
        id: NCIT:C770
        label: Prednisone
  target_mechanisms:
  - target: Bursal Macrophage and Synoviocyte Activation
    description: >-
      Broad, non-specific suppression of the bursal inflammatory infiltrate,
      which is why response is rapid but relapse follows withdrawal.
    evidence:
    - reference: PMID:37832573
      reference_title: "Polymyalgia rheumatica."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Glucocorticoids at 12·5-25·0 mg prednisone per day are effective in inducing remission in most individuals"
      explanation: >-
        Establishes glucocorticoid efficacy at inducing remission of the
        inflammatory process.
  target_phenotypes:
  - preferred_term: Arthralgia
    term:
      id: HP:0002829
      label: Arthralgia
  - preferred_term: Joint stiffness
    term:
      id: HP:0001387
      label: Joint stiffness
  evidence:
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "A dose of 12·5-25·0 mg prednisolone daily or equivalent leads to rapid improvement of symptoms in most patients with isolated disease."
    explanation: >-
      Independent statement of the effective dose range and the rapidity of
      response, carrying the dose claim this treatment description makes.
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "However, relapses are common when prednisolone is tapered."
    explanation: >-
      Confirms relapse on tapering as the limitation of glucocorticoid
      monotherapy, which is what motivates the steroid-sparing agents below.
- name: Methotrexate
  description: >-
    The conventional steroid-sparing DMARD, and the option that predates IL-6
    blockade. In a randomised placebo-controlled trial added to tapering
    prednisone, more patients were off prednisone at 76 weeks, fewer had a
    flare, and the cumulative prednisone dose was lower. Unlike tocilizumab it
    is not directed at a specific node of the mechanism; it is included because
    presenting IL-6 blockade as the only steroid-sparing route would misstate
    the therapeutic landscape, and the EULAR/ACR recommendations cover DMARDs
    explicitly.
  therapeutic_modality: SMALL_MOLECULE
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: methotrexate
      term:
        id: CHEBI:44185
        label: methotrexate
  target_phenotypes:
  - preferred_term: Arthralgia
    term:
      id: HP:0002829
      label: Arthralgia
  evidence:
  - reference: PMID:15466766
    reference_title: "Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Twenty-eight of 32 patients in the methotrexate group and 16 of 30 patients in the placebo group were no longer taking prednisone at 76 weeks (P = 0.003)."
    explanation: >-
      Randomised evidence that adding methotrexate increases the proportion of
      patients who come off prednisone.
  - reference: PMID:15466766
    reference_title: "Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Prednisone plus methotrexate is associated with shorter prednisone treatment and steroid sparing."
    explanation: >-
      Trial conclusion establishing the steroid-sparing effect.
  - reference: PMID:28774422
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "Methotrexate might be used in patients who relapse."
    explanation: >-
      Places methotrexate in the treatment pathway for relapsing disease.
  notes: >-
    No target_mechanisms link. Methotrexate's mechanism in PMR is not resolved to
    a node in this pathograph, and asserting one would overstate what the trial
    shows -- the endpoints are steroid sparing and relapse, not a measured
    mechanistic effect.
- name: IL-6 Receptor Blockade
  description: >-
    Tocilizumab, an IL-6 receptor inhibitor, targets the amplification loop
    directly rather than suppressing inflammation broadly. In new-onset disease
    with rapid steroid tapering it tripled the rate of glucocorticoid-free
    remission, delayed relapse and lowered cumulative steroid dose. Sarilumab has
    also shown efficacy. This is the mechanistically motivated therapy: it
    predicts, and delivers, steroid sparing rather than merely additional
    anti-inflammatory effect.
  therapeutic_modality: MONOCLONAL_ANTIBODY
  treatment_term:
    preferred_term: Pharmacotherapy
    term:
      id: NCIT:C15986
      label: Pharmacotherapy
    therapeutic_agent:
    - preferred_term: tocilizumab
      term:
        id: NCIT:C84217
        label: Tocilizumab
  target_mechanisms:
  - target: IL-6 Amplification Loop
    description: >-
      Blocking the IL-6 receptor interrupts the feed-forward loop in which
      synoviocyte-derived IL-6 drives further synoviocyte proliferation.
    evidence:
    - reference: PMID:35210264
      reference_title: "Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial."
      supports: SUPPORT
      evidence_source: HUMAN_CLINICAL
      snippet: "Glucocorticoid-free remission at week 16 was achieved in 12 out of 19 patients on tocilizumab (63.2%) and 2 out of 17 patients receiving placebo (11.8%, p=0.002)"
      explanation: >-
        Randomised evidence that IL-6 receptor blockade induces
        glucocorticoid-free remission, supporting the IL-6 loop as the operative
        mechanism.
  target_phenotypes:
  - preferred_term: Arthralgia
    term:
      id: HP:0002829
      label: Arthralgia
  evidence:
  - reference: PMID:35210264
    reference_title: "Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "In patients with new onset polymyalgia rheumatica undergoing rapid glucocorticoid tapering, tocilizumab was superior to placebo regarding sustained glucocorticoid-free remission, time to relapse and cumulative glucocorticoid dose."
    explanation: >-
      Trial conclusion establishing tocilizumab's steroid-sparing benefit across
      three endpoints.
  - reference: PMID:37832573
    reference_title: "Polymyalgia rheumatica."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "tocilizumab and sarilumab have shown efficacy in randomised controlled trials and additional targeted therapies are emerging"
    explanation: >-
      Confirms randomised-trial efficacy for both IL-6 receptor inhibitors used
      in this disease.
clinical_trials:
- name: NCT03263715
  phase: PHASE_II
  status: COMPLETED
  description: >-
    PMR-SPARE: double-blind, multi-centre phase 2/3 trial of subcutaneous
    tocilizumab versus placebo in 36 patients with new-onset polymyalgia
    rheumatica undergoing rapid prednisone tapering.
  target_phenotypes:
  - preferred_term: Arthralgia
    term:
      id: HP:0002829
      label: Arthralgia
  evidence:
  - reference: PMID:35210264
    reference_title: "Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial."
    supports: SUPPORT
    evidence_source: HUMAN_CLINICAL
    snippet: "we randomly assigned 36 patients with new onset polymyalgia rheumatica from three centres to receive subcutaneous tocilizumab (162 mg per week) or placebo for 16 weeks"
    explanation: >-
      Describes the trial design and randomisation reported for this registered
      study.
📚

References & Deep Research

References

8
PMID:37832573
Polymyalgia rheumatica.
No top-level findings curated for this source.
PMID:41107118
Understanding the immunopathophysiology of polymyalgia rheumatica: implications for treatment.
No top-level findings curated for this source.
PMID:21565899
Imaging of polymyalgia rheumatica: indications on its pathogenesis, diagnosis and prognosis.
No top-level findings curated for this source.
PMID:35210264
Tocilizumab in patients with new onset polymyalgia rheumatica (PMR-SPARE): a phase 2/3 randomised controlled trial.
No top-level findings curated for this source.
PMID:26359488
2015 Recommendations for the management of polymyalgia rheumatica: a European League Against Rheumatism/American College of Rheumatology collaborative initiative.
No top-level findings curated for this source.
PMID:15466766
Prednisone plus methotrexate for polymyalgia rheumatica: a randomized, double-blind, placebo-controlled trial.
No top-level findings curated for this source.
PMID:15305244
HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: influence on clinical subgroups and prognosis.
No top-level findings curated for this source.
PMID:28774422
Polymyalgia rheumatica.
No top-level findings curated for this source.