---
type: source
title: "GLP-1 Adherence Collapse at Year 1-2 — Lower-Income Groups Show Higher Discontinuation; Medicaid PA More Restrictive Than FDA"
author: "Penn LDI / AJMC / Multiple sources"
url: https://ldi.upenn.edu/our-work/research-updates/patients-face-new-barriers-for-glp-1-drugs-like-wegovy-and-ozempic/
date: 2025-01-01
domain: health
secondary_domains: []
format: article
status: unprocessed
priority: high
tags: [GLP-1, adherence, discontinuation, Medicaid, low-income, access-barriers, prior-authorization, commercial-insurance, equity]
---

## Content

Synthesis of adherence and access barrier evidence for GLP-1 obesity therapy:

**AJMC adherence study (commercially insured, n=16 million+ patients without diabetes, 2021):**
- 1-year adherence for Wegovy: 36%
- 1-year adherence for Ozempic: 47%
- 2-year adherence (follow-on study, presented April 2025): only 14.3% of patients still on therapy
- This is COMMERCIAL insurance — the best-coverage, highest-income population

**Discontinuation determinants:**
- Higher discontinuation: lower-income groups, multiple health conditions, age over 65
- High costs, lack of insurance coverage, and adverse effects drive discontinuation
- For lower-income populations: out-of-pocket cost is cited as the primary barrier even when drugs are technically covered

**Medicaid prior authorization specifics:**
- 70% of Medicaid PA policies specify conditions more restrictive than FDA-approved criteria
- Typical PA requirements: documented diet/exercise failure, specific BMI thresholds above FDA minimum, specific comorbidity combinations
- Prior authorization is functionally a clinical gatekeeping mechanism that the healthcare system uses to limit access beyond what the FDA deems clinically appropriate

**Penn LDI framing:**
- "Patients face new barriers" — not old barriers, new ones emerging in 2025-2026 as states cut coverage, Medicaid implements stricter PA, and insurance denials persist

**The arithmetic of the access gap:**
- If 36-47% of commercially insured patients (with the best coverage) adhere at year 1, and GLP-1 benefits require continuous delivery...
- Then Medicaid patients — with PA more restrictive than FDA, higher cost barriers, higher burden of social determinants affecting adherence — likely have substantially lower adherence rates
- The compounding: (lower adherence) × (higher baseline metabolic disease burden) × (continuous delivery required for effect) = the population most needing the intervention has the least sustained access to it

## Agent Notes

**Why this matters:** The 14.3% two-year adherence figure in commercially insured patients is the most alarming datum in the GLP-1 adherence literature. Combined with the Session 20 finding (GLP-1 benefits revert within 1-2 years of cessation), 85.7% of commercially insured patients on GLP-1s are not achieving durable metabolic benefit — because they've discontinued before the rebound occurs. For Medicaid patients with additional barriers, the number is likely worse.

**What surprised me:** That the 14.3% two-year adherence figure is from COMMERCIAL insurance (April 2025 presentation). I expected adherence to be better in commercial populations. The fact that even well-insured patients can't sustain GLP-1 therapy past 2 years at scale means the adherence problem isn't primarily financial — there's a broader behavioral/pharmacological challenge that financial coverage alone doesn't solve. This COMPLICATES the access-as-solution narrative.

**What I expected but didn't find:** A direct study comparing Medicaid vs. commercial insurance adherence rates for GLP-1 obesity treatment. That comparison doesn't appear to exist yet as a published study — likely because Medicaid coverage has been so limited that there's no large population to study. The direct comparison is a genuine research gap.

**KB connections:**
- Supports Session 20's finding: `2026-04-08-bcbs-glp1-persistence-doubled.md` — BCBS persistence data (also commercial)
- The continuous-treatment model (Sessions 20-21): 85.7% non-adherers won't achieve durable benefit
- The access infrastructure collapse (this session, multiple sources): Medicaid coverage cuts
- Together: the population with highest metabolic burden has both lowest access AND likely lowest adherence

**Extraction hints:**
- Claim: "GLP-1 two-year adherence is only 14.3% in commercially insured patients, meaning the continuous-delivery infrastructure required for durable metabolic benefit is not being maintained even in the best-coverage population — and is almost certainly lower in Medicaid and uninsured populations"
- This is a complicating finding: the problem isn't only access (coverage), it's also adherence (sustained delivery). The solution requires BOTH coverage AND support infrastructure.
- Note the Medicaid PA finding (70% more restrictive than FDA) as an administrative gatekeeping mechanism above clinical evidence.

**Context:** Penn LDI (Leonard Davis Institute of Health Economics at University of Pennsylvania) is a leading health policy research institution. The AJMC study (16 million patients) is one of the largest real-world adherence analyses for GLP-1 in obesity treatment.

## Curator Notes (structured handoff for extractor)

PRIMARY CONNECTION: Continuous-treatment model (Session 21 musing) and the GLP-1 adherence literature thread
WHY ARCHIVED: The 14.3% two-year adherence figure in the BEST-coverage population reveals that the access problem is not just financial — it's behavioral/pharmacological adherence combined with financial barriers. This complicates the "expand coverage → solve the problem" narrative in a KB-valuable way.
EXTRACTION HINT: Two claims: (1) GLP-1 2-year adherence at 14.3% even in commercial insurance; (2) the combination of low adherence + continuous-delivery requirement = most patients aren't achieving durable benefit even when covered. The Medicaid PA (70% more restrictive than FDA) is a separate, extractable claim.
