Which Health Conditions Predict Whether Patients Stick With GLP-1 Drugs? | Research

The takeaway

Patients with more comorbidities like high cholesterol and kidney disease were more likely to stay on GLP-1 drugs, while GI side effects and heart disease reduced adherence.

69,049 patients
Large cohort revealing that comorbidities significantly predict first-year GLP-1 adherence across drug types and indications

What the researchers found

Among 69,049 adults who started GLP-1 receptor agonists, comorbidities significantly influenced first-year adherence. Patients with diabetes who also had hyperlipidemia (OR 1.17), chronic kidney disease (OR 1.14), or hypertension (OR 1.06) were more likely to stay on their GLP-1 medication. Conversely, cardiovascular disease (OR 0.90) and digestive side effects (OR 0.94) reduced adherence.

Similar patterns held for patients with obesity. Findings were consistent across different GLP-1 RA brands, suggesting these adherence patterns are class-wide rather than drug-specific.

Why it matters

With tens of millions of people now taking GLP-1 drugs, understanding who stays on them is critical. This study reveals that patients with more health conditions (except cardiovascular disease) are actually more adherent — possibly because they perceive greater benefit. Digestive side effects remain a key barrier, highlighting the need for better side effect management to improve persistence.

The numbers in context

n=69,049 · 59.3% with diabetes · 74.4% with obesity · Hyperlipidemia OR 1.17 · CKD OR 1.14 · ASCVD OR 0.90 · GI adverse events OR 0.94

How the study worked

Retrospective cohort study using the University of California Health Data Warehouse. Adults initiating GLP-1 RAs between 2018–2023 were identified. First-year adherence was the primary outcome, analyzed against baseline comorbidities and digestive adverse events using logistic regression. Analyses were stratified by indication (diabetes vs. obesity) and drug subtype.

Who was studied

69,049 adults initiating GLP-1 receptor agonists for diabetes or obesity across University of California health systems (2018–2023)

What this study cannot tell us

Observational design cannot establish causation. Adherence was measured from health system records, which may not capture medications obtained elsewhere. The study cannot determine patient motivations for continuation or discontinuation. University of California health system patients may not be representative of all GLP-1 users nationally.

How to read the evidence

Large retrospective cohort study with nearly 70,000 patients providing robust statistical power. The multi-center UC Health system adds breadth, though observational design limits causal inference.

When this study was published

Published in 2025 with data through 2023, this is very current research addressing one of the most pressing practical questions in GLP-1 drug management.

The bigger picture

GLP-1 drug adherence is a growing public health concern — multiple studies show 30–50% of patients stop within a year. Understanding predictors of adherence can help clinicians identify patients at risk of dropping off and intervene proactively. The finding that sicker patients (except those with cardiovascular disease) stick with therapy better challenges assumptions about medication burden.

Questions still open

Why does cardiovascular disease reduce GLP-1 adherence despite these drugs having proven CV benefits?
Would proactive GI side effect management (antiemetics, slower titration) improve adherence in patients experiencing digestive issues?
How do insurance coverage and cost interact with comorbidity-driven adherence patterns?

Common questions

Why do people with more health problems stay on GLP-1 drugs longer?

The study didn't determine causation, but patients with conditions like high cholesterol and kidney disease may have stronger motivation to manage their health, more regular contact with healthcare providers, or greater perceived benefit from the medication. They may also have more experience taking medications consistently.

Do GI side effects really cause people to stop GLP-1 drugs?

Yes — digestive side effects like nausea, vomiting, and diarrhea are among the most common complaints with GLP-1 drugs. This study found that experiencing GI adverse events reduced first-year adherence by about 6%. Strategies like slower dose titration and managing expectations may help patients push through the initial adjustment period.

Read the original research

Association of Baseline Comorbidities With First-Year Adherence to GLP-1 Receptor Agonists in Patients With Diabetes or Obesity: A Retrospective Cohort Study.

The Annals of pharmacotherapy, 10600280251384637

View on PubMed ↗Publisher’s paper ↗

Citation

Mai, Ziyang; Kornak, John; Dufault, Suzanne M; Strand, Michael W; Reikes, Andrew R; Watanabe, Jonathan H. (2025). Association of Baseline Comorbidities With First-Year Adherence to GLP-1 Receptor Agonists in Patients With Diabetes or Obesity: A Retrospective Cohort Study.. The Annals of pharmacotherapy, 10600280251384637. https://doi.org/10.1177/10600280251384637