Bulimia Nervosa — Comprehensive Research Report

1. Disease Information

Overview. Bulimia nervosa (BN) is a psychiatric eating disorder characterized by recurrent episodes of binge eating (rapid consumption of an objectively large amount of food accompanied by a subjective sense of loss of control) followed by inappropriate compensatory behaviors intended to prevent weight gain — most commonly self-induced vomiting, but also laxative/diuretic/enema misuse, fasting, or excessive/compulsive exercise. Self-evaluation is disproportionately influenced by body shape and weight. Unlike anorexia nervosa, body weight in BN is typically within or above the normal range, which contributes to underrecognition (MRCPsych UK, ICD-11 criteria; StatPearls).

Key identifiers: - MONDO: MONDO:0005452 (bulimia nervosa) — confirmed via OLS/Monarch query (EBI OLS4 API, 2026-07-29 query) - OMIM: 607499 — "BULIMIA NERVOSA, SUSCEPTIBILITY TO; BULN" (a susceptibility locus entry, not a monogenic disorder) (OMIM:607499) - DOID: DOID:12129 - ICD-10-CM: F50.2 (Bulimia nervosa); ICD-11: 6B81 - ICD-11 diagnostic code: 6B81 - EFO: EFO_0005204 - HPO: HP:0100739 "Bulimia" (synonym: "Binge and purge") — confirmed via OLS4 API query - MeSH: D002032 (Bulimia Nervosa)

Synonyms: Bulimia, binge-purge syndrome, bulimarexia (historical, now discouraged).

Evidence base: Predominantly aggregated disease-level literature (case series, clinical cohorts, epidemiological registries, twin/family studies, GWAS meta-analyses, RCTs). Individual-patient EHR-level data exist but are less centralized than for BED/AN; national inpatient databases (e.g., US Nationwide Inpatient Sample) provide some individual-level aggregated statistics (PMC6034764).

Sources: ICD-11 Criteria (MRCPsych), StatPearls: Bulimia Nervosa, OMIM:607499

2. Etiology

Disease causal model: BN is multifactorial/polygenic — no single causal gene; risk arises from an interaction of genetic vulnerability (heritability ~50–60%), neurobiological reward/impulse-control dysregulation, and environmental/psychosocial exposures (sociocultural thin-ideal internalization, dieting, trauma).

Genetic risk factors

• Heritability: Twin studies estimate BN heritability at ~50–60% (one classic study: heritability of liability 55%; a subsequent twin study ~41%; proband-wise concordance 22.9% MZ vs. 8.7% DZ twins) (PubMed:1842216 — Kendler et al., "The genetic epidemiology of bulimia nervosa").
• Genetic correlation with anorexia nervosa: rg 0.46–0.79, indicating substantial shared genetic architecture between AN and BN (Nature Transl Psychiatry, 2023).
• GWAS: The Psychiatric Genomics Consortium – Eating Disorders (PGC-ED) is actively collecting BN samples; a 2025 GWAS of binge-eating behavior and anorexia nervosa found shared and unique genetic architecture across ED phenotypes (medRxiv 2025.01.31.25321397). A dedicated, well-powered BN-specific GWAS with genome-wide-significant loci has not yet been published (as of 2026), in contrast to AN (first genome-wide-significant locus reported in Watson et al. 2019, chr12).
• Candidate gene studies (largely underpowered/candidate-gene era, mixed replication):
• 5-HTTLPR (serotonin transporter promoter polymorphism, SLC6A4/hgnc:11050): implicated in reward processing, impulsivity, and eating-disorder susceptibility in meta-analyses; effects reported are inconsistent across studies.
• BDNF Val66Met (rs6265, hgnc:1033): studied primarily in AN; not robustly associated in BN-specific analyses.
• OPRD1 (delta-opioid receptor) and HTR1D: association signals reported with eating-disorder susceptibility (primarily AN datasets, with BN comorbid samples).
• ESR1/ESR2 (estrogen receptor genes): implicated given menstrual-cycle-linked binge-eating fluctuations.
• Note on evidence quality: Most single-candidate-gene associations in BN come from small case-control samples and have not been replicated in well-powered GWAS; treat as evidence_source: HUMAN_CLINICAL with low confidence pending GWAS confirmation.

Environmental / psychosocial risk factors

• Sociocultural pressure/thin-ideal internalization and dieting behavior are established proximal risk factors — strict caloric restriction predisposes to disinhibited binge eating (PMC2907970).
• Childhood sexual abuse and maltreatment: Childhood sexual abuse is a replicated non-specific risk factor for BN (elevated risk vs. no-ED controls, though not specific to BN vs. other psychiatric disorders) (PubMed, Am J Psychiatry 1992; ScienceDirect 1993).
• Adverse childhood experiences (ACEs): emotional, physical, and sexual abuse and emotional neglect show a dose-dependent relationship with eating-disorder symptom severity, including in BN (Frontiers 2022; PMC8860810).
• Perfectionism (particularly self-oriented perfectionism) and low self-esteem/body dissatisfaction are robust psychological risk factors.
• Sex: female sex is the strongest demographic risk factor (see §9).
• Family history of eating disorders, depression, substance use, or obesity.
• Weight stigma / weight-based teasing and participation in weight-class or appearance-focused activities (dance, gymnastics, modeling).

Protective factors

• Limited high-quality literature specifically on protective genetic variants. Environmentally, protective factors include: family meal structure/cohesion, media-literacy interventions, and body-acceptance-based prevention programs (see §13). No confirmed protective allele has reached genome-wide significance specifically for BN.

Gene-environment interaction

• The interaction of genetic loading (reward/impulsivity circuitry variants) with dieting/restriction as an environmental trigger is the dominant conceptual G×E model — caloric restriction unmasks binge-eating vulnerability in genetically susceptible individuals, consistent with rodent binge-eating-prone (BEP) vs binge-eating-resistant (BER) models responding differentially to identical intermittent palatable-food-access protocols (PMC3132131).

Sources: Kendler et al. PMID:1842216, Nature Transl Psychiatry 2023, PMC2907970, Frontiers 2022 ACEs

3. Phenotypes

Onset: Typically late adolescence to early adulthood (median onset ~18–21 years); can follow a period of dietary restriction or, less commonly, transition from anorexia nervosa (AN-restricting → BN crossover reported in a subset of AN patients) (PMC2275291).

Severity (DSM-5) is graded by weekly frequency of inappropriate compensatory behaviors: - Mild: 1–3 episodes/week - Moderate: 4–7 episodes/week - Severe: 8–13 episodes/week - Extreme: ≥14 episodes/week

Course: Episodic/fluctuating with a tendency toward chronicity if untreated; partial and full remission specifiers apply (see §8, §11).

Quality of life impact: Significant impairment in psychosocial functioning, social withdrawal (due to secrecy around bingeing/purging), impaired occupational/educational functioning, and elevated suicide risk associated with comorbid depression.

Sources: Cleveland Clinic J Med, StatPearls, ScienceDirect salivary gland, PMC2275291

4. Genetic / Molecular Information

• Causal genes: None establish a monogenic cause; BN is polygenic/multifactorial (OMIM 607499 is explicitly a "susceptibility" entry, not a Mendelian disease locus).
• Pathogenic variants: Not applicable in the classical Mendelian sense. No ClinVar pathogenic/likely-pathogenic variant classifications exist for BN as a discrete monogenic trait.
• Susceptibility loci / candidate genes (see §2 for detail): SLC6A4 (5-HTTLPR), BDNF (Val66Met/rs6265), OPRD1, HTR1D, ESR1/ESR2 — candidate-gene-era findings, generally not replicated at genome-wide significance.
• Polygenic architecture: Significant genetic correlation with anorexia nervosa (rg 0.46–0.79) and likely with major depression, anxiety disorders, OCD, and impulsivity/ADHD traits, consistent with the high psychiatric comorbidity burden (§9 below; Nature Transl Psychiatry 2023).
• Epigenetics: Limited direct BN-specific data; eating-disorder epigenetics literature (largely AN-focused) has examined DNA methylation changes in genes related to appetite regulation (e.g., POMC, AGRP) but BN-specific methylation studies are sparse and not yet conclusive.
• Chromosomal abnormalities: None established as causal for BN.
• Modifier genes: Not well characterized specifically for BN; impulsivity- and reward-related gene variants may modify symptom severity/course but data are preliminary.

Suggested gene terms if annotating candidate associations (low-confidence, candidate-gene-era evidence — flag accordingly): hgnc:11050 (SLC6A4), hgnc:1033 (BDNF), hgnc:8156 (OPRD1), hgnc:3444 (ESR1).

Sources: OMIM:607499, Nature Transl Psychiatry 2023, Frontiers 2024 AN polymorphisms

5. Environmental Information

• Sociocultural exposures: Media/thin-ideal internalization, social-media use (a Lebanese university-student study found problematic social media use associated with BN symptoms mediated by anxiety/depression — PMC10052263), weight stigma, appearance-focused athletic/artistic activities.
• Lifestyle factors: Chronic dieting/caloric restriction is the most consistently identified proximal behavioral trigger; alcohol/substance use frequently co-occurs and may share impulsivity-driven risk pathways.
• Life stress/trauma: Childhood abuse/neglect (§2), interpersonal stressors, and transitions (e.g., leaving home, athletic competition pressure).
• Infectious agents: Not applicable — BN has no known infectious etiology.

Sources: PMC10052263, NEDA Risk Factors

6. Mechanism / Pathophysiology

BN pathophysiology is best modeled as a reward-circuitry and homeostatic-appetite-signaling dysregulation cascade, upstream of the behavioral binge-purge cycle, with secondary systemic/metabolic consequences downstream of purging behaviors.

Causal chain (upstream → downstream)

1. Trigger: Caloric restriction/dieting (behavioral) and/or genetic predisposition (reward/impulsivity circuitry variants) →
2. Gut-hormone/appetite-signaling dysregulation: Impaired meal-induced ghrelin suppression, blunted postprandial cholecystokinin (CCK) rise, and lower postprandial leptin — collectively reducing satiety signaling and promoting continued/disinhibited intake (PMC3782835; ResearchGate ghrelin/leptin study) →
3. Mesolimbic reward-circuit hyperresponsivity: Altered dopamine D1/D2 receptor balance and interaction with serotonergic (mood/anxiety) systems in ventral striatum, orbitofrontal cortex; corticostriatal circuitry changes parallel those seen in substance-use disorders (ScienceDirect reward dysregulation; PMC3366171) →
4. Impaired top-down inhibitory control: Altered functional connectivity between dorsolateral prefrontal cortex (self-regulation) and striatum (reward), plus insular hyperactivity to food cues driving impulsive/compulsive food approach (PMC7311647 / Int J Neuropsychopharmacol 2020; Frontiers 2022 OFC) →
5. Binge-eating episode (loss-of-control overconsumption) →
6. Compensatory purging behavior (self-induced vomiting most common; laxative/diuretic misuse; excessive exercise), driven by shape/weight overvaluation and anxiety-reduction reinforcement (negative reinforcement loop: purging transiently reduces post-binge distress, reinforcing the cycle) →
7. Systemic/metabolic sequelae: Recurrent vomiting → gastric acid exposure to oral cavity/esophagus → dental enamel erosion (perimyolysis), esophagitis, rare Mallory-Weiss tears/Boerhaave esophageal rupture; hydrochloric acid and fluid loss → hypochloremic, hypokalemic metabolic alkalosis (pseudo-Bartter physiology via chronic volume depletion → secondary hyperaldosteronism) → risk of QTc prolongation and arrhythmia (torsades de pointes); salivary gland (parotid) hypertrophy with elevated serum amylase.

Gut-brain axis

Vagal gut-brain signaling governs mesolimbic dopamine dynamics; gut microbial metabolites (short-chain fatty acids, bile acids, tryptophan metabolites) and microbially synthesized neurotransmitters (dopamine, serotonin, GABA) may modulate reward-driven eating behavior, an emerging area of interest connecting the gut microbiome to BN's binge phenotype (PMC12857734; Bulimia Nervosa and Depression, gut microbiota).

Molecular pathways / GO term suggestions

• Serotonergic signaling: GO:0007210 serotonin receptor signaling pathway
• Dopaminergic reward signaling: GO:0007212 dopamine receptor signaling pathway
• Appetite regulation / satiety: GO:0032100 positive regulation of appetite; GO:0032099 negative regulation of appetite
• Response to nutrient levels / feeding behavior: GO:0007631 feeding behavior

Cell types / anatomical substrates (CL/UBERON suggestions)

• Neurons of ventral striatum/nucleus accumbens (reward): CL:0000540 neuron (generic; more specific CL terms for medium spiny neurons: CL:0000842? verify via OAK)
• Hypothalamic arcuate nucleus neurons (appetite regulation)
• Parotid gland acinar cells (secondary complication): UBERON:0001830 parotid gland

Biochemical abnormalities

Hypokalemia (HP:0002900), hypochloremia, metabolic alkalosis, hyperamylasemia (salivary isoenzyme predominance) — direct consequences of purging, not primary disease mechanism, but clinically critical downstream nodes.

Immune involvement

Not a primary feature; no established autoimmune/inflammatory mechanism in BN specifically (contrast with some appetite-neuropeptide-autoantibody findings reported in AN — PMC3782835 discusses "mixed" orexigenic/anorexigenic autoantibody signals relevant to both AN and BN, an area of ongoing investigation).

Model-system caveat

Much of the gut-hormone and reward-circuit mechanistic evidence blends human clinical (fMRI, hormone assay) studies with rodent binge-eating-prone (BEP) models; rodent bingeing models capture caloric/palatability-driven overconsumption and associated anxiety-like behavior but do not fully recapitulate purging behavior or the cognitive shape/weight-overvaluation component — a human-model mismatch worth flagging if curated as a HUMAN_MODEL_MISMATCH discussion.

Sources: PMC3782835, PMC12857734, ScienceDirect reward dysregulation, PMC7311647, Frontiers 2022 OFC VBM/FC, PMC6379643

7. Anatomical Structures Affected

Organ level (primary): Central nervous system (reward/limbic circuitry, hypothalamus) — primary driver; secondary/complication organs: gastrointestinal tract (oral cavity, esophagus, stomach), salivary glands (parotid), cardiovascular system (arrhythmia risk from electrolyte disturbance), renal system (electrolyte/fluid balance), endocrine/reproductive system (menstrual irregularity), dental/oral structures.

Body systems involved: Nervous (CNS reward/cognitive control), digestive (esophagus, salivary glands, dental enamel), cardiovascular, renal, endocrine/reproductive, psychiatric/behavioral.

UBERON suggestions: - UBERON:0001630 muscle organ / UBERON:0006562 — not directly relevant - UBERON:0001043 esophagus - UBERON:0001830 parotid gland - UBERON:0001723 tooth enamel (or UBERON:0001754 tooth) - UBERON:0002107 liver — not primary but monitored in refeeding/metabolic workups - UBERON:0002037 cerebellum / UBERON:0002420 basal ganglia (striatum) — reward circuitry - UBERON:0001876 amygdala

Tissue/cell level: Dental enamel (acid erosion), esophageal squamous epithelium (irritation/tears), parotid acinar tissue (hypertrophy), gastric mucosa.

Subcellular: Not a primary organelle-level disease; mitochondrial/oxidative changes are not established mechanistic features.

Lateralization: Not applicable (systemic/bilateral/symmetric where relevant, e.g., bilateral parotid enlargement).

Sources: Cleveland Clinic J Med, ScienceDirect salivary gland enlargement

8. Temporal Development

• Onset: Adolescence to early adulthood; median age of onset typically 18–21 years, though onset can occur earlier (early teens) or later. Onset pattern is typically insidious, often emerging after a period of dietary restriction (subacute/gradual).
• Progression: Variable — can remain stable, progress in severity/frequency, or fluctuate episodically; DSM-5 severity specifiers (mild/moderate/severe/extreme) are frequency-based, not stage-based.
• Disease course pattern: Predominantly episodic/relapsing-remitting; approximately two-thirds of patients achieve substantial improvement or recovery long-term, with frequent relapses in between, and 15–20% follow a chronic protracted course (Am J Psychiatry, "Outcome of bulimia nervosa" 2009; PubMed:19884225).
• Remission patterns: Both spontaneous and treatment-induced remission occur; risk of relapse declines notably after ~4 years post-presentation. Full and partial remission are formal DSM-5 specifiers.
• Critical periods: Adolescence/young adulthood represents the key vulnerability window (developmental identity formation + peak dieting-behavior prevalence); early intervention within the first few years of illness onset is associated with better prognosis.

Sources: PubMed:9054777, PubMed:19884225, PubMed:9892257

9. Inheritance and Population

Epidemiology

• Lifetime prevalence: 0.8–2.6% among women; 0.1–0.2% among men (some sources cite up to 3% of females and >1% of males) (search synthesis of multiple epidemiological reviews).
• Global burden trend: Age-standardized prevalence increased ~43% globally from 1990–2021 (EAPC 0.57); burden correlates positively with socioeconomic development; Australia had the highest burden in 2021; fastest growth in East and South Asia; decline in high-income North America (PMC12164058; J Eating Disorders 2025).
• Age distribution: Most common in adolescents (10–19y) and young adults (20–40y), especially in Western/high-income countries.

Inheritance pattern

Multifactorial/polygenic — not Mendelian. OMIM designates a "susceptibility" locus construct (607499), consistent with complex trait architecture. - Heritability: ~50–60% (twin studies). - Penetrance/expressivity: Not applicable in the Mendelian sense; risk is probabilistic/polygenic, modulated heavily by environmental exposure (dieting, trauma). - Genetic anticipation, germline mosaicism, founder effects, consanguinity, carrier frequency: Not applicable to this polygenic behavioral/psychiatric disorder.

Population demographics

• Sex ratio: Strongly female-predominant (historically cited ~10:1 female:male in clinical samples, though population-based estimates suggest a narrower gap and rising recognition in males).
• Geographic distribution: Higher burden in higher-SES/Western countries historically; rapidly rising in East/South Asia; regional variation reflects both true prevalence differences and detection/reporting differences.

Sources: PMC8500372, PMC12164058, Oxford Academic Eur J Public Health 2026

10. Diagnostics

Clinical/laboratory tests

• Electrolytes: Serum potassium, chloride, bicarbonate — screen for hypokalemic, hypochloremic metabolic alkalosis (most common abnormality, ~27.4% of BN patients show metabolic alkalosis; hypochloremia ~23.8%; hypokalemia ~13.7%) (search synthesis of medical-complications literature).
• Serum amylase: Elevated (salivary isoenzyme) correlating with binge/purge frequency and parotid enlargement — useful non-invasive marker of active purging (ScienceDirect).
• ECG: To assess QTc interval, especially with significant hypokalemia — risk of torsades de pointes.
• Dental exam: Perimyolysis (lingual-surface enamel erosion of maxillary teeth) is a sensitive clinical sign of chronic self-induced vomiting (PMC11986531 dentin hypersensitivity study).
• Imaging: Not routinely required for diagnosis; used if complications suspected (e.g., chest/abdominal imaging for suspected esophageal rupture).

Genetic testing

Not clinically indicated — BN is not a Mendelian/single-gene disorder; no diagnostic genetic test exists.

Screening tools

• SCOFF questionnaire: 5-item screen (Sick, Control, One stone, Fat, Food); cutoff ≥2 "yes" answers; sensitivity 84.6%, specificity 89.6% in primary care, detecting all AN and BN cases and 77% of EDNOS in the validating study (search synthesis).
• EDE-Q (Eating Disorder Examination Questionnaire): 28-item self-report across 4 subscales (restraint, eating concern, shape concern, weight concern); optimal global-score cutoff ≥2.80 (sensitivity/specificity ~0.80/0.80) (ScienceDirect EDE-Q vs SCOFF).

Clinical diagnostic criteria

• DSM-5: Recurrent binge eating + recurrent inappropriate compensatory behavior, both occurring on average ≥1×/week for 3 months; self-evaluation unduly influenced by shape/weight; not occurring exclusively during AN episodes.
• ICD-11 (6B81): Similar core criteria; frequency threshold ≥1×/week for ≥1 month; notably includes "subjective binges" (loss of control even without objectively large intake) — a key ICD-11/DSM-5 divergence. About 98% diagnostic concordance between ICD-11 and DSM-5 in inpatient samples (PMC6515596).
• Differential diagnosis: Anorexia nervosa binge-purge subtype (distinguished by significantly low body weight), binge-eating disorder (no regular compensatory behavior), Kleine-Levin syndrome, atypical depression with hyperphagia, Prader-Willi syndrome (in relevant developmental contexts), medical causes of vomiting.

Sources: SCOFF validation, ICD-11 field study PMC6515596, PMC11986531

11. Outcome/Prognosis

• Mortality: Crude mortality rate ~0.3% across pooled follow-up studies (7 deaths/2,194 subjects, likely an underestimate given short follow-up); more recent cohort analyses indicate a ~50% increased risk of death (all-cause) relative to general population (PubMed:23771148 — longitudinal mortality study).
• Long-term recovery: At 5–10 years, ~50% fully recover; ~20% continue to meet full BN criteria; ~30% relapse into bulimic symptoms after initial improvement (risk of relapse declines after ~4 years) (PubMed:9054777).
• Quarter-century synthesis: ~45% full recovery on average, ~27% considerable improvement, ~23% chronic protracted course (Am J Psychiatry 2009).
• Prognostic factors: Impulsivity (personality trait) associated with poorer outcome; comorbid depression/substance use predicts persistence (ScienceDirect comorbid depression/substance use); treatment speeds recovery but doesn't strongly alter outcome beyond 5 years post-presentation.
• Complications driving morbidity: Electrolyte-disturbance-related cardiac arrhythmia, GI complications (Mallory-Weiss tear, rare Boerhaave esophageal rupture), dental damage, and psychiatric comorbidity burden (depression, anxiety, substance use) are the principal drivers of long-term morbidity.
• QoL: Chronic BN is associated with substantial reduction in psychosocial functioning and quality of life, improving with successful treatment.

Sources: PubMed:23771148, PubMed:9054777, Am J Psychiatry 2009

12. Treatment

Pharmacotherapy

• Fluoxetine (SSRI; CHEBI:5118): The only FDA-approved medication for BN, at a higher dose (60 mg/day) than typical antidepressant dosing. RCT evidence: fluoxetine reduces core binge/purge symptoms and psychological features in the short term (PubMed:9299800; systematic review PubMed:17370288).
• Combination fluoxetine + CBT: All three arms (fluoxetine alone, CBT alone, combination) showed improvement in an RCT; combination was superior to medication alone on some parameters but not significantly superior to CBT alone (PubMed:9299800).
• Topiramate (anticonvulsant, off-label): Reduces binge urges via effects on appetite/impulse-control-relevant neurotransmission; studied in partial responders (NCT00988481).
• Lisdexamfetamine (psychostimulant, FDA-approved for BED, off-label in BN): Emerging open-label feasibility data in BN adults show reductions in binge/purge frequency (PMC10204259); case-series data on psychostimulants generally show reduced binge/purge days (PubMed:28111772).

Psychotherapy (first-line)

• Cognitive Behavioral Therapy (CBT), including enhanced CBT (CBT-E): Leading evidence-based treatment; reduces core behavioral/psychological features in short and long term (systematic review PubMed:17370288). MAXO suggestion: cognitive behavioral therapy — closest MAXO/NCIT term should be verified via OAK (NCIT:C49236 Therapeutic Procedure as a fallback if no specific CBT term exists).
• Interpersonal psychotherapy (IPT): An evidence-based alternative, slower onset of effect but comparable longer-term outcomes to CBT in some trials.
• Guided self-help CBT models have been piloted in non-Western settings (e.g., Japan) with promising feasibility (PMC5918895; PMC7041176).

Nutritional/behavioral/supportive

• Nutritional counseling/rehabilitation, regular meal-pattern restoration, and psychoeducation are standard adjunctive components.
• Group therapy formats are under active study (e.g., "Step by Step Group Therapy for Bulimia Nervosa" — NCT06063278).
• Physical exercise and dietary therapy have been compared to CBT in RCT protocols (PED-t trial — PMC5427572).

Medical/supportive management of complications

Electrolyte repletion (aggressive potassium correction to prevent arrhythmia), dental care, and monitoring for esophageal injury in severe purging.

Experimental / advanced therapeutics

No gene therapy, cell therapy, or immunotherapy approaches are applicable — BN is a behavioral/psychiatric disorder, not amenable to these modalities. Active clinical trial areas include neurobiological/fMRI-guided treatment-response studies (e.g., "Neurobiology of Bulimia Nervosa" — NCT04225221) and self-control/impulsivity-targeted interventions (NCT04409457).

Treatment algorithm

Guideline-concordant stepped care: CBT-E (or IPT) as first-line psychotherapy; fluoxetine as first-line/adjunctive pharmacotherapy or for partial responders; topiramate/psychostimulants as off-label augmentation in treatment-resistant cases; inpatient/higher level of care for medical instability (severe electrolyte disturbance, cardiac risk).

Suggested MAXO terms: MAXO:0000950 supportive care (nutritional/medical monitoring), pharmacotherapy generically under NCIT:C15986, with therapeutic_agent CHEBI binding to fluoxetine (CHEBI:5118) and topiramate; psychotherapy modality would need a dedicated MAXO/NCIT lookup (verify via OAK — likely closest is a general "psychotherapy" or "behavioral therapy" NCIT term).

Sources: PubMed:9299800, PubMed:17370288, PMC10204259, PubMed:28111772

13. Prevention

• Primary prevention: School- and media-literacy-based programs targeting thin-ideal internalization, body dissatisfaction, and dieting behavior; universal and targeted (high-risk) prevention curricula have shown modest efficacy in reducing eating-disorder risk-factor endorsement.
• Secondary prevention/early detection: Primary-care screening with SCOFF or EDE-Q in at-risk populations (adolescent girls, athletes in weight-sensitive sports, individuals with early dieting behavior or subthreshold binge/purge symptoms).
• Tertiary prevention: Relapse-prevention components within CBT-E; ongoing monitoring of electrolytes/dental health in patients with residual purging behavior to prevent life-threatening complications (arrhythmia, esophageal rupture).
• Behavioral interventions: Reducing dieting behavior, promoting normalized eating patterns, media-literacy and body-acceptance interventions.
• Counseling: Family-based approaches and psychoeducation for caregivers; no genetic counseling role given the polygenic, non-Mendelian architecture.
• Public health: Broader social-media/advertising regulation discussions around thin-ideal content; weight-stigma reduction campaigns.
• Immunization/prophylaxis: Not applicable.

Sources: General synthesis from NEDA risk factors and prevention literature cited in etiology searches above.

14. Other Species / Natural Disease

BN as clinically defined (with its cognitive component of shape/weight overvaluation) is a human-specific psychiatric construct; there is no known naturally occurring veterinary analog in companion animals or wildlife, and no OMIA entry exists for a bulimia-like natural disease. This is distinct from binge-eating/palatability-driven overconsumption, which is modeled experimentally (see §15).

• Taxonomy: Not applicable for natural disease.
• Zoonotic potential: Not applicable.

15. Model Organisms

BN pathophysiology (specifically the binge-eating component) is modeled almost exclusively via induced rodent models, since no genetic/knockout model recapitulates the full human syndrome (including purging and cognitive shape/weight overvaluation).

• Binge-Eating-Prone (BEP) / Binge-Eating-Resistant (BER) rat model: Rats undergo repeated intermittent exposure to palatable food; individual variation in over- vs under-consumption identifies BEP vs. BER phenotypes, used to study neurobiological risk factors for binge eating (Springer protocol).
• Sugar-bingeing / intermittent access model: Periodic (e.g., 12-hour) food restriction followed by scheduled access to 25% glucose or 10% sucrose solution; over ~3 weeks produces a bingeing pattern (up to 32% of caloric intake from sugar), used as a model of behavioral/neurochemical "sugar addiction" relevant to binge-type eating disorders (PMC4361030).
• Neurochemical findings from these models: Altered dopamine D1/D2 receptor balance, changes in midbrain serotonin neurotransmission — mirroring hypothesized human corticostriatal reward dysregulation (ScienceDirect; PMC3366171).
• Behavioral readouts: Elevated Plus-Maze anxiety-like behavior is increased (small effect size) across pooled rodent binge-eating studies (systematic review/meta-analysis of 18 studies) (ScienceDirect meta-analysis).
• Model limitations: Rodent bingeing models do not capture compensatory purging behavior, body-image/shape-weight cognitive overvaluation, or the menstrual-cycle/estrogen-linked symptom fluctuation seen in humans — an important human-model-mismatch caveat for any hypothesis-flagged pathophysiology node built from these data.
• Applications: Used to dissect neurochemical/circuit-level contributions to loss-of-control eating, palatability-driven reward, and pharmacological screening (e.g., topiramate, opioid-antagonist, and serotonergic-agent testing) relevant to BN's binge component.

Sources: PMC3132131, Springer BEP/BER protocol, PMC4361030, MDPI 2023 rodent pharmacotherapy review

Summary of Key Ontology Term Suggestions

Notes on Evidence Gaps for Curation

1. No BN-specific genome-wide-significant GWAS locus has been published as of this report (contrast with AN); candidate-gene findings (5-HTTLPR, BDNF, OPRD1, ESR1) should be curated as evidence_source: HUMAN_CLINICAL with an explicit caveat about small-sample/candidate-gene-era limitations, or considered for a KNOWLEDGE_GAP discussion entry.
2. No dedicated HP terms exist for several clinically important signs (Russell's sign, perimyolysis/dental erosion, parotid enlargement specifically) — these will need either a best-fit broader HP term or documentation via notes/free text rather than a forced ontology binding.
3. Rodent binge-eating models do not recapitulate purging or cognitive shape/weight overvaluation — a strong candidate for a HUMAN_MODEL_MISMATCH discussion node if a MODEL_ORGANISM-sourced pathophysiology claim (e.g., dopamine D1/D2 imbalance) is included.
4. All PMIDs/URLs above should be independently re-verified against cached abstracts (just fetch-reference) and exact-quote snippets extracted before use in KB YAML, per dismech's evidence SOP — this report is a research lead document, not pre-validated curation content.

Sources (consolidated): - ICD-11 Criteria for Bulimia Nervosa (MRCPsych UK) - ICD-11 field study, PMC6515596 - StatPearls: Bulimia Nervosa - OMIM:607499 - Kendler et al., PMID:1842216 - Nature Translational Psychiatry 2023 - PMC2907970 — Bulimia nervosa review - Frontiers 2022 — ACEs and eating disorders - PMC8860810 — childhood maltreatment network analysis - PMC3782835 — orexigenic/anorexigenic autoantibodies - PMC12857734 — gut-brain vagal axis and dopamine - ScienceDirect — reward system dysregulation animal models - PMC3366171 - PMC7311647 / Int J Neuropsychopharmacol 2020 - Frontiers 2022 — OFC VBM/FC study - PMC6379643 — resting-state fMRI BED/BN - Cleveland Clinic Journal of Medicine — medical complications - ScienceDirect — salivary gland enlargement/amylase - PMC4392812 — medical complications review - PMC11986531 — dentin hypersensitivity in BN - PMC6034764 — hospitalization outcomes/comorbidities - PubMed:9299800 — fluoxetine + CBT RCT - PubMed:17370288 — treatment systematic review - PMC10204259 — lisdexamfetamine feasibility trial - PubMed:28111772 — psychostimulants case reports - NCT00988481 — topiramate augmentation - NCT06063278 — group therapy - NCT04225221 — neurobiology of BN - PubMed:23771148 — longitudinal mortality study - PubMed:9054777 — outcome in bulimia nervosa - Am J Psychiatry 2009 — quarter-century outcome review - PMC8500372 — incidence/prevalence/mortality review - PMC12164058 — GBD 2021 analysis - PMC2275291 — AN-restricting to BN transition - PMC3132131 — rat models of binge eating - PMC4361030 — sugar addiction rat model - Springer protocol — BEP/BER model - PubMed:18359005 — EDE-Q vs SCOFF screening