Nearly three out of four patients struggled to consistently take their GLP-1 medication, even when their out-of-pocket costs were relatively low.
Researchers found that adherence dropped more sharply when monthly costs exceeded about $75.
Patients paying more than $168 per month had the highest rate of nonadherence, highlighting how insurance costs can affect access to treatment.
GLP-1 medications have become a popular option for people looking to lose weight, but getting a prescription is only part of the equation. For some patients, the ongoing cost of treatment may make it difficult to keep taking their medication consistently.
A new study from researchers at the University of Georgia, published in JAMA Health Forum, found that higher out-of-pocket costs for semaglutide, a GLP-1 medication used for weight management, were associated with lower medication adherence. The researchers identified a notable turning point at around $75 per month, when patients became more likely to fall behind on their prescriptions.
“That surprised me because when I first ran this analysis, I expected a clear linear association between higher out-of-pocket costs and lower adherence, but that wasn’t the case,” researcher Eunhae Shin said in a news release. “Until people reached that $75 tipping point, they were similar in terms of adherence.”
How researchers studied GLP-1 costs
The research team analyzed insurance claims data for 8,914 adults with obesity who started taking semaglutide for weight loss. Participants had commercial health insurance and were continuously enrolled in their plans during the study period. People with type 2 diabetes were excluded.
Researchers examined treatment starts between June 2021 and December 2022 and tracked medication use over the following year. They divided patients into five groups based on their out-of-pocket costs for a 30-day supply: $0 to $21, $22 to $43, $44 to $75, $76 to $168, and more than $168.
To measure adherence, the team looked at how consistently patients had medication available over time. They also accounted for factors such as age, sex, insurance plan type, geographic location and certain health conditions when evaluating the relationship between costs and medication use.
The study was observational, meaning it identified associations between medication costs and adherence rather than proving that higher prices alone caused patients to take their medication less consistently.
What the findings mean for consumers
The results showed that medication adherence was a challenge across every cost group.
However, the problem became more pronounced among patients paying more. After adjusting for other factors, researchers estimated that nonadherence affected about 75% to 77% of patients in the three lowest-cost groups, compared with nearly 80% of those paying $76 to $168 and about 85% of those paying more than $168 per month.
Patients in the highest-cost group were also more likely to have high-deductible health insurance plans. These plans can leave patients responsible for a larger share of medication expenses, particularly before they meet their deductibles.
The researchers noted that eligible Medicare patients may benefit from a $50 monthly copayment under a federal initiative, but similar cost reductions are not expected to apply broadly to commercial insurance plans.
For consumers, the takeaway is that insurance coverage doesn't necessarily make GLP-1 treatment affordable. Anyone struggling with medication costs can discuss their options with their healthcare provider and insurance plan rather than changing or stopping treatment without medical guidance.
“The key takeaway from our study is that out-of-pocket costs matter,” Shin said. “And this question is so timely and important because of what’s going on in the policy space.
“If the goal is to improve medication adherence and have as many people benefit from these drugs as possible, we should start thinking about how to restructure out-of-pocket costs and insurance design.”