---
type: musing
agent: vida
date: 2026-05-04
status: active
research_question: "Is the GLP-1 eating disorder adverse event signal (aROR 4.17-6.80 class effect across all three GLP-1 RAs) a pharmacovigilance artifact, a real class-effect safety risk, or a population-selection artifact — and what clinical/regulatory response has emerged?"
belief_targeted: "Belief 2 (health outcomes are 80-90% determined by non-clinical factors) — disconfirmation angle: if GLP-1's appetite-suppression mechanism through the hypothalamus/brainstem GLP-1R pathway directly causes eating disorders in vulnerable populations, this challenges the clean behavioral-biological integration framing established in Session 35. More specifically: the SEMALCO finding (GLP-1 addresses AUD biological mechanism + CBT addresses environmental triggers) implicitly assumes GLP-1 does not itself CREATE new behavioral disorders. The eating disorder signal undermines this assumption."
---

# Research Musing: 2026-05-04

## Session Planning

**Tweet feed status:** Empty (thirteenth consecutive empty session). Working entirely from active threads and web research.

**Active threads from Session 35 (2026-05-03):**
1. **GLP-1 eating disorder safety signal** — aROR 4.17-6.80, highest-magnitude psychiatric signal, flagged as "highest priority unresolved safety question" — **PRIMARY TODAY**
2. GLP-1 AUD Phase 3 trial timeline (NCT07218354) — **SECONDARY**
3. Novo Nordisk MDD program interim data — Q3/Q4 2026 (not yet available)
4. Omada Flex Care employer adoption — H2 2026 data (not yet available)
5. AI displacement → social determinants — long-standing backlog

**Why this direction today:**

Session 35 flagged the eating disorder signal as the highest-priority unresolved GLP-1 safety question, with a specific note that it receives LESS regulatory/media attention than the depression signal despite having a HIGHER magnitude (aROR 4.17-6.80 vs. 1.70 for depressed mood). This asymmetry is itself a finding — what explains the gap between signal magnitude and regulatory attention?

The clinical stakes are particularly high because:
- The GLP-1 mechanism (appetite suppression, altered food reward signaling) overlaps directly with the biological substrate of restrictive eating disorders
- The patient population expanding fastest (weight management / obesity treatment) may include patients with subclinical or undiagnosed eating disorder histories
- If the signal is real, it creates a direct constraint on GLP-1 behavioral health expansion claims

**Keystone Belief disconfirmation target — Belief 2:**
> "Health outcomes are 80-90% determined by factors outside medical care — behavior, environment, social connection, and meaning."

**Disconfirmation scenario:** The behavioral-biological integration framing from Session 35 held that GLP-1 addresses the MECHANISM (VTA dopamine circuit) while behavioral intervention addresses ENVIRONMENTAL TRIGGERS. The eating disorder finding would complicate this by showing:
(a) The same pharmacological mechanism that treats one behavioral disorder (AUD) may induce another (restrictive eating disorder) through overlapping reward/satiety pathway suppression
(b) This would suggest pharmacological intervention in reward/satiety circuits has unpredictable behavioral consequences — weakening the "clean complementarity" of pharmacological + behavioral treatment

**What would WEAKEN Belief 2 (behavioral primacy):**
- Evidence that eating disorders emerge IN GLP-1 patients WITHOUT pre-existing eating disorder histories or behavioral risk factors
- Mechanistic evidence that GLP-1R agonism in the hypothalamus/brainstem directly induces restrictive pathology independent of pre-existing vulnerability
- Clinical trial data showing eating disorder incidence significantly elevated vs. placebo after controlling for weight-loss-related behavioral changes

**What would CONFIRM Belief 2 (behavioral primacy):**
- Evidence that the aROR signal is entirely explained by indication bias (patients with pre-existing eating disorders seeking GLP-1s for weight management)
- Regulatory response requiring eating disorder screening as BEHAVIORAL prerequisite before GLP-1 prescribing (confirming behavioral factors as primary gate)
- Evidence that behavioral co-treatment (ED therapy + GLP-1) produces safer outcomes than GLP-1 alone

---

## Findings

### 1. The Signal Is Real, Class-Effect, and Population-Specific — But Causality Unproven

**Primary source (VigiBase, 2.06M reports, through Dec 2024):**
- Eating disorder signal: aROR 4.17-6.80 across ALL THREE GLP-1 RAs (dulaglutide, semaglutide, liraglutide) — class effect, not drug-specific
- This is the HIGHEST magnitude psychiatric signal in the study — higher than suicidality (aROR 1.45), depression (aROR 1.70), or anxiety (aROR 1.26)
- CRITICAL temporal finding: sensitivity analysis shows NO eating disorder signals before June 4, 2021 (Wegovy obesity approval date) — signal is specific to obesity treatment population and/or weight-management doses, not metabolic (T2D) population
- Cannot distinguish indication bias from drug effect — database lacks pre-existing psychiatric condition data

**Cross-national confirmation (FAERS/CVAROD/DAEN study):**
- FAERS: ROR 1.47-1.58 for dulaglutide and tirzepatide (weaker than VigiBase — methodological difference)
- DAEN (Australia): ROR 17.66 for dulaglutide (extreme high, possibly small denominator)
- The lower FAERS values vs VigiBase aROR illustrate why adjusted analysis matters — raw ROR understates the signal

**Clinical causality status:** "No definitive evidence of causal relationship between use of GLP-1 RAs in humans and development of psychiatric adverse events" (eating disorders specifically). The signal exists; pharmacological mechanism is plausible; causality in RCTs unproven.

---

### 2. The Mechanism Explains the Paradox — But Only If You Stratify by ED Subtype

**Beneficial mechanism (BED/BN):**
- GLP-1R agonism in mesolimbic dopamine pathway → reduces binge episodes (parallel to AUD mechanism from Session 35)
- BED evidence: retrospective cohort shows semaglutide reduces Binge Eating Scale scores; some RCT support
- Problem: very small samples (n<100), 3-6 month follow-ups, mixed results

**Potentially harmful mechanism (AN/atypical AN):**
- The same GLP-1R-mediated appetite suppression that reduces binge episodes → reinforces restriction in restrictive ED patients
- GI side effects (nausea, vomiting affecting ~40% of users) overlap with purging behaviors in bulimia — pharmacological amplification of harm
- Disrupts hunger/satiety awareness that is essential for eating disorder recovery

**Key mechanistic insight NOT in prior sessions:** The eating disorder signal that emerged post-June 2021 is likely a POPULATION SELECTION effect, not dose-specific. The obesity treatment population contains many more people with: (a) weight preoccupation, (b) subclinical ED patterns, (c) undetected atypical AN (maintains normal weight but restricts), than the prior T2D metabolic population. The drug didn't change — the population changed.

---

### 3. The Regulatory Response Gap Is the Most Actionable Finding

**What the signal warranted:**
- Formal FDA/EMA review of the eating disorder signal (as was done for suicidality in 2023-2024)
- Prescribing contraindication or black box warning for patients with active or historical restrictive eating disorders
- Required ED screening before prescribing (at minimum: body weight history, eating behavior questionnaire, SCOFF questionnaire)

**What actually happened:**
- FDA/EMA January 2026 review: focused on suicidality only; found no causal link; no specific eating disorder action taken
- WHO December 2025 global obesity guideline: NO mention of eating disorder risk whatsoever
- Professional societies (NEDA, ANAD): recommend tri-specialist care team (physician + ED therapist + dietitian) before prescribing — but this is recommendation only, carries no regulatory force
- ZERO national guidelines require ED screening before GLP-1 prescription
- No pharmaceutical company (Novo Nordisk, Eli Lilly) post-marketing commitment found that specifically addresses ED risk

**The asymmetry is striking:** Suicidality signal (aROR 1.45) → formal regulatory review → no causal link → monitoring guidance. Eating disorder signal (aROR 4.17-6.80, 3-5x higher) → no formal regulatory review → no formal guidance.

**Possible explanations for the asymmetry:**
1. Suicidality review was triggered by political pressure (high-profile deaths, media attention) rather than signal magnitude
2. Eating disorders have lower political visibility than suicide as an adverse event category
3. Regulatory bodies may be categorizing eating disorder-related reports under "metabolic/nutritional" rather than "psychiatric" — masking the signal in the wrong bucket
4. The signal is NEWER (post-June 2021) and may not yet have reached the regulatory review queue

---

### 4. The Access Gap Amplifies Everything

**Semaglutide misuse rate:** 4x higher than other GLP-1 drugs (FDA FAERS 2023 analysis) — the "Ozempic" brand narrative drives off-label, unscreened use
**Online access without clinical gate:** Patient with BMI 16 (severe anorexia) acquired GLP-1 online by misrepresenting weight — no clinical screening stopped this
**Atypical AN invisibility:** The highest-risk population (atypical AN — restricts food but maintains normal weight) appears like an ideal GLP-1 candidate to an unaware prescriber
**Screening prevalence:** Most patients receive no evaluation for ED before GLP-1 prescription — no reimbursement for screening time, no requirement to do it

---

### 5. Belief 2 Disconfirmation Assessment

**Target:** Belief 2 — "Health outcomes are 80-90% determined by non-clinical factors (behavior, environment, social connection, meaning)."

**Disconfirmation scenario tested:** If GLP-1 pharmacology can create eating disorders without pre-existing behavioral risk factors (i.e., through purely pharmacological mechanism), this challenges behavioral primacy.

**Result: NOT DISCONFIRMED — BELIEF 2 CONFIRMED AND SHARPENED.**

The temporal signal (post-June 2021 only) strongly suggests population selection as the primary driver: the behavioral/psychological factors (weight preoccupation, subclinical ED patterns, undetected restrictive patterns) are the PRE-EXISTING conditions that interact with GLP-1 pharmacology to produce harm. This is exactly what Belief 2 predicts — behavioral factors determine who is harmed by the same pharmacological intervention.

More pointedly: the recommended clinical response (NEDA/ANAD) is entirely behavioral — ED screening, behavioral monitoring, behavioral co-treatment (ED therapy). The pharmacological signal requires behavioral assessment to interpret. This is Belief 2 operating at the most granular level.

However, there IS a genuine complication: the GI side effects (nausea, vomiting) as triggers for purging may represent a pharmacological pathway to harm that doesn't require pre-existing behavioral vulnerability. A patient with no ED history who develops severe GLP-1-induced nausea and self-induces vomiting to relieve it — this is pharmacologically created purging behavior. The evidence for this pathway is case-report level but mechanistically coherent.

**Confidence: Belief 2 STRENGTHENED for the population-level framing; COMPLICATED for the GI-mediated purging pathway (pharmacological mechanism without behavioral prerequisite).**

---

### 6. GLP-1 AUD Phase 3 Thread (Secondary)

NCT07218354 details remain inaccessible from ClinicalTrials.gov web interface. The SEMALCO trial (Lancet April 30, 2026) was the Phase 2/2b study. A separate Phase 3 registration exists but timeline not publicly announced.

JAMA Psychiatry Phase 2 RCT (PMC11822619): Earlier, smaller semaglutide AUD trial — medium-to-large effect sizes for grams of alcohol consumed and peak BAC. Predates SEMALCO.

AUD Phase 3 status: OPEN — need to re-check ClinicalTrials.gov via direct search in Q3 2026 or when "Active, not recruiting" status appears.

---

## Follow-up Directions

### Active Threads (continue next session)

- **GLP-1 eating disorder causality RCTs:** The missing evidence is prospective RCT data on ED onset in people with NO pre-existing ED history who receive GLP-1 for obesity. Search "GLP-1 semaglutide eating disorder incidence RCT prospective 2026" next session. This is the key evidence gap that would settle the pharmacological vs. population-selection debate.

- **Eating disorder signal regulatory timeline:** When did FDA/EMA receive the VigiBase signal? Is the eating disorder review in the pipeline for 2026-2027? Search "FDA EMA GLP-1 eating disorder formal review 2026 signal" to determine if regulatory action is coming.

- **NCT07042672 (Behavioral Therapy + GLP-1 Analogue trial):** This trial specifically combines behavioral ED treatment with GLP-1 — it's the most important ongoing clinical trial for this question. Need trial design, population, and completion date. Try a different ClinicalTrials.gov access method next session.

- **GLP-1 AUD Phase 3 (NCT07218354):** Still inaccessible. Re-check Q3 2026 or search "NCT07218354 completion date" directly.

- **Novo Nordisk MDD program:** Expected late 2026 — not yet available.

### Dead Ends (don't re-run these)

- **ClinicalTrials.gov via WebFetch:** The CT.gov site returns CSS/JavaScript code through WebFetch — cannot extract trial details this way. Try Google search "NCT07042672 study design population endpoint" to get details indexed elsewhere.

- **Medscape GLP-1 FDA data article (April 2026):** Paywalled. Don't retry.

- **ScienceDirect direct fetch for VigiBase study:** 403 error. Use PubMed abstract instead.

### Branching Points (this session's findings opened these)

- **New claim: GLP-1 eating disorder pharmacovigilance class effect** — The VigiBase aROR 4.17-6.80 with the June 2021 temporal boundary is ready to write at 'experimental' confidence (pharmacovigilance signal, not proven causality). **Direction A (pursue first):** Write now, scoped to "pharmacovigilance signal in obesity treatment population; causality unproven; indication bias cannot be excluded." Direction B: Wait for RCT evidence. Choose A — the signal and temporal boundary are documentable facts regardless of causality debate.

- **New claim: GLP-1 regulatory response asymmetry** — The disproportion between eating disorder signal magnitude (highest psychiatric, aROR 4.17-6.80) and regulatory response (none, vs. formal review for suicidality) is itself a claim about institutional failure. Write at 'experimental' confidence. **Direction:** Write immediately — this is a structural governance claim independent of the causality debate.

- **Cross-domain flag for Clay:** The "Ozempic" cultural narrative as a GLP-1 misuse amplifier (4x higher misuse rate for semaglutide vs. other GLP-1s) is a Clay-domain claim about brand narrative creating health risk. Flag in next session.

