The study, conducted by researchers at the University of Mississippi School of Pharmacy in partnership with the Mississippi Division of Medicaid and published in Advances in Therapy, analyzed deidentified administrative claims from January 2023 through December 2025. The team identified 8,495 GLP-1 receptor agonist users overall and narrowed the cohort to 3,968 adults who initiated therapy between July 2023 and June 2025, each with six months of continuous enrollment before and after starting the medication. The population was strikingly homogeneous: 92.52 percent were female, 50.28 percent were Black, and nearly 62 percent were younger adults aged 18 to 39. Hypertension and depression were the most common coexisting conditions, and most members were enrolled in managed care organizations rather than fee-for-service plans.

The headline numbers tell a story of steady erosion. Mean adherence, measured by the proportion of days covered, a standard metric that divides the total days a patient has medication on hand by the total days in the observation window, stood at 0.76 at three months but fell to 0.65 by six months. The proportion of members meeting the conventional adherence threshold of at least 80 percent of days covered dropped from 56.85 percent at three months to 38.16 percent at six months. Persistence, defined as continuous therapy without a gap of 60 days or more, followed the same downward slope, falling from 72.98 percent to 51.03 percent over the same interval. In the subgroup followed for a full year, mean adherence sank to 0.54, with only 25.26 percent adherent and 36.67 percent persistent.

What makes this study particularly valuable is its timing. Most prior real-world analyses of GLP-1 adherence were conducted during the nationwide drug shortage that ran from 2022 through February 2025, a period when supply constraints made it nearly impossible to distinguish voluntary discontinuation from involuntary interruption. Because this analysis extends through December 2025, it captures one of the first pictures of adherence under conditions of stable drug availability. The researchers found that adherence improved progressively across initiation cohorts: members who started therapy in the first half of 2025 consistently outperformed those who began in 2024, who in turn fared better than the 2023 pioneers. Among 2023 initiators, only 47.77 percent were adherent at three months, compared with 61.01 percent of 2025 initiators.

To move beyond aggregate statistics, which can mask enormous individual variation, the team employed group-based trajectory modeling, a statistical technique that clusters individuals who follow similar longitudinal patterns of behavior. The model input was the continuous proportion of days covered calculated for each 30-day interval, and the optimal five-group quadratic solution was selected using the Bayesian Information Criterion, the logged Bayes factor, a minimum group membership threshold of five percent, and clinical interpretability. The result was a taxonomy of medication-taking behavior that is far more nuanced than a single adherence rate could ever convey.

The largest group, comprising 52.27 percent of members, was labeled consistent adherent, maintaining high medication coverage throughout follow-up. The remaining members scattered across four suboptimal pathways. The delayed decliner group, 13.53 percent of the cohort, held steady for roughly three months before sliding. The consistent decliner group, 12.85 percent, showed a steady reduction from the outset. The fluctuating adherent group, 11.14 percent, cycled through declines and partial recoveries, a pattern that may reflect intermittent access barriers or wavering motivation. Most concerning was the rapid discontinuer group, 10.21 percent, who abandoned therapy by the second month and never returned, a trajectory often associated with early adverse effects such as nausea and gastrointestinal distress, or with immediate obstacles to refilling prescriptions.

Multinomial logistic regression, using the consistent adherent group as the reference, illuminated who was most at risk of falling off course. Members who initiated therapy in July through December 2023 had more than twice the odds of becoming rapid discontinuers compared with 2025 initiators, an odds ratio of 2.10, likely reflecting the chaos of the shortage era. Age mattered profoundly: members aged 40 to 64 had significantly lower odds of suboptimal trajectory membership than those aged 18 to 39, perhaps because younger patients perceive less disease severity, have shallower roots in the healthcare system, and face fewer obesity-related complications that motivate sustained treatment. Black members had higher odds of belonging to the rapid discontinuer and fluctuating adherent groups than white members, a disparity the authors attribute to structural and socioeconomic barriers rather than race itself. Enrollment in a managed care organization was protective, cutting the odds of rapid discontinuation by roughly a third, presumably because care coordination, medication management programs, and proactive outreach help keep patients engaged in ways that fragmented fee-for-service coverage cannot.

Clinical characteristics painted a more complicated picture. Type 2 diabetes and cardiovascular comorbidities were associated with higher odds of suboptimal trajectories, possibly reflecting greater clinical complexity and competing therapeutic priorities that crowd out obesity treatment. Hypertension, paradoxically, was protective, reducing the odds of delayed decliner membership. Sex showed no significant association, a departure from prior studies, though the authors note their cohort was so overwhelmingly female, reaching 93 percent of initiators in early 2025, that detecting sex differences may have been statistically impractical. Sleep apnea, fatty liver disease, hyperlipidemia, kidney conditions, and depression were not significantly linked to trajectory membership.

The policy implications are considerable. As of January 2026, only 13 state Medicaid programs covered at least one GLP-1 receptor agonist approved for weight management, and several have since withdrawn or restricted coverage. Coverage alone, the Mississippi experience suggests, is insufficient to guarantee therapeutic engagement. Fewer than five percent of initiators in the program received counseling services before starting therapy, a strikingly low uptake given that discontinuation is consistently associated with rapid weight regain and loss of cardiometabolic benefit. The authors argue for expanded care management, patient education, behavioral counseling, and side effect support, alongside robust lifestyle programs that can mitigate regain among those who stop the drugs. The temporal improvement across cohorts also offers a hopeful signal: fixing structural access barriers, as the shortage resolution did, produces measurable gains in continuity. For the other states weighing coverage decisions, Mississippi’s data provide a rare, unvarnished look at what happens when expensive, effective medications meet a high-need population, and a reminder that the hardest part of obesity pharmacotherapy may begin not at the first injection, but at the second and every one after.

Subject of Research: Real-world adherence and persistence to GLP-1 receptor agonist anti-obesity medications among Medicaid enrollees

Article Title: Real-World Adherence Patterns and Predictors of GLP-1 Receptor Agonist Use for Obesity Management in a Medicaid Population

Article References: Bazzazzadehgan, S., Pittman, E., Lin, L.-Y., Qi, J., Ly-Ha, A., Smith, D., Kirby, T., Vest, T. A., Bentley, J. P., & Bhattacharya, K. (2026). Real-World Adherence Patterns and Predictors of GLP-1 Receptor Agonist Use for Obesity Management in a Medicaid Population. Advances in Therapy. https://doi.org/10.1007/s12325-026-03806-x

Image Credits: AI Generated

DOI: 10.1007/s12325-026-03806-x

Keywords: GLP-1 receptor agonists, anti-obesity medications, Medicaid, medication adherence, persistence, group-based trajectory modeling, obesity, health disparities, Mississippi, drug shortage, proportion of days covered, health policy

The research, published in the International Journal of Obesity, exploits one of the distinctive strengths of the Nordic research infrastructure. In Finland, comprehensive national registers record prescription drug purchases, healthcare utilization, education, income, employment status, family structure and place of residence for virtually the entire population. By linking these registers at the individual level, researchers can assemble an exceptionally complete picture of medication use across society, free from the recall bias, volunteer bias and loss to follow-up that plague conventional surveys. This makes register studies of this kind uniquely suited to detecting systematic patterns in who accesses treatment and who is left behind.

The scale of the analyzed population matters for the credibility of the findings. With more than a quarter of a million Finnish adults in the study cohort, even relatively small differences in medication uptake between social groups become statistically detectable, and the results are far less likely to be distorted by random variation. Small clinical studies, which typically follow a few hundred patients at specialized obesity clinics, capture only the narrow slice of people who reach tertiary care. A register study, by contrast, observes the full pipeline, from primary care prescriptions through pharmacy dispensing records, and therefore reflects everyday clinical practice rather than the highly selected environment of academic weight-management centers.

Why should the distribution of anti-obesity medication be socially patterned at all? In principle, obesity is not distributed evenly across society in the first place. Decades of epidemiological research, particularly in high-income countries, have consistently shown that obesity prevalence is inversely associated with socioeconomic position: people with lower levels of education and income carry a higher burden of obesity in many populations. If treatment followed need, one would therefore expect anti-obesity medications to be prescribed at least as often, and possibly more often, to people from disadvantaged backgrounds. Whether that is actually the case is the empirical question at the heart of the Finnish register study.

The answer is far from guaranteed, because multiple forces pull access in different directions. On one side sit barriers that tend to concentrate among socioeconomically disadvantaged groups: out-of-pocket medication costs, the ability to navigate healthcare systems, geographic distance from providers who prescribe these drugs, and the time and flexibility required for the frequent follow-up appointments that anti-obesity pharmacotherapy typically demands. On the other side sit factors that may favor advantaged groups or, in some contexts, disadvantage them differently, including physician prescribing preferences, awareness of and demand for newer therapies, and insurance or reimbursement structures that determine how much of the medication price each patient must shoulder.

Anti-obesity pharmacotherapy is also a moving target, and this temporal dimension shapes any register analysis. Older agents, such as orlistat, which acts by inhibiting intestinal fat absorption, and older noradrenergic appetite suppressants, have been joined in recent years by glucagon-like peptide-1 receptor agonists originally developed for type 2 diabetes and subsequently approved for chronic weight management. These newer agents have demonstrated substantially greater average weight loss in randomized trials, but they are also expensive, administered by weekly injection, and often subject to reimbursement restrictions and supply shortages. The social profile of who uses anti-obesity medications is therefore not static; it evolves as the drug landscape, the regulatory environment and public attention to obesity treatment change.

Register data allow researchers to trace these patterns across the entire adult population, stratifying medication use by sex, age, education, income, employment and family circumstances. This multidimensional approach is important because socioeconomic position is not a single variable. Education captures early-life and cognitive resources, income captures current material means, and employment captures attachment to institutions that shape healthcare access. Different dimensions can point in different directions: for instance, medication use might rise with income while showing a different gradient with age or family status. Only a sufficiently large and richly linked dataset can disentangle these overlapping gradients, which is precisely the analytical opportunity afforded by the Finnish registers.

Finland offers a particularly informative setting for this kind of inquiry. Like its Nordic neighbors, it provides tax-funded healthcare to all residents, which softens but does not eliminate the role of purchasing power in treatment access. Prescription medications in Finland are subject to a tiered reimbursement system administered through the national health insurance scheme, and anti-obesity drugs have historically faced strict limits on reimbursement, leaving many patients to pay substantial costs out of pocket. Primary health centers deliver most routine care, while referral pathways govern access to specialized obesity treatment. How these institutional arrangements translate into equitable or inequitable access is exactly the sort of question that register linkage can address with a precision unattainable in most other countries.

The stakes of the question extend well beyond Finland. Health systems worldwide are confronting an unprecedented surge in demand for anti-obesity medications, driven both by rising obesity prevalence and by the demonstrated efficacy of newer agents. Supply constraints, insurance coverage debates and clinical guideline decisions all hinge on assumptions about who benefits from and who deserves access to these therapies. If real-world uptake is systematically skewed by education, income or demography, then the newest and most effective obesity treatments risk widening existing health inequalities rather than narrowing them, echoing patterns previously documented for bariatric surgery, where uptake has often been concentrated among groups that are urban, insured and socioeconomically advantaged despite obesity being more prevalent elsewhere.

For researchers, the Finnish register study of 282,307 adults provides a template for monitoring this emerging therapeutic landscape systematically. For clinicians and policymakers, it underscores that the effectiveness of anti-obesity medications in populations depends not only on their performance in randomized trials but on whether the people who need them most actually receive them. As new agents enter the market and reimbursement policies are revised, continued surveillance of sociodemographic and socioeconomic gradients in medication use will be essential to ensure that the pharmacological revolution in obesity treatment reaches all segments of society rather than only those already best positioned to seize it.

Subject of Research: Sociodemographic and socioeconomic differences in anti-obesity medication use among Finnish adults

Article Title: Sociodemographic and socioeconomic differences in the use of anti-obesity medications: a register study among 282,307 Finnish adults

Article References: Valkonen, J., Svärd, A. C., Roos, E., Joki, A., Kouvonen, A., & Lallukka, T. (2026). Sociodemographic and socioeconomic differences in the use of anti-obesity medications: a register study among 282,307 Finnish adults. International Journal of Obesity. https://doi.org/10.1038/s41366-026-02213-0

Image Credits: AI Generated

DOI: 10.1038/s41366-026-02213-0

Keywords: anti-obesity medications, socioeconomic differences, register study, Finland, obesity treatment, health inequality, pharmacotherapy, prescription drugs, obesity epidemiology, healthcare access, Sociodemographic, socioeconomic