Three Sides to the Story: Adherence Trajectories During the First Year of Sodium–Glucose Cotransporter 2 Inhibitor Therapy Among Medicare Beneficiaries

Abstract

<b>Objective</b> <a>We aimed to understand the factors associated with SGLT2i adherence and longitudinal adherence trajectories</a> in older adults with type 2 diabetes. <p><b>Research Design and Methods</b> Using Medicare claims data (April 2013-December 2017), we identified 83,675 new SGLT2i users aged ≥66 years old with type 2 diabetes. We measured SGLT2i adherence as the Proportion of Days Covered (PDC) during the first year of SGLT2i therapy. We used linear regression to assess the association between baseline covariates and PDC. <a>Then we used group-based trajectory modeling to identify distinct longitudinal SGLT2i adherence groups and used a multivariable logistic regression model to examine the association between baseline covariates and membership in these adherence groups. <br> <b>Results </b>Unadjusted mean PDC was 63%. Previous adherence to statins had the strongest positive association with PDC [regression coefficient 6.00% (95% CI, 5.50%,6.50%)], whereas female sex [-5.51% (-6.02%, -5.00%)], and Black race/ethnicity [-5.06% (-6.03%, -4.09%)] had the strongest negative association. We identified three adherence trajectory groups: low (23% of patients, mean PDC: 17%), moderate (32%, mean PDC: 50%), or high adherence (45%, mean PDC 96%). More patients in the high adherence group were previously adherent to statins [OR 1.43 (95% CI 1.39,1.48)], and more women [1.28 (1.23,1.32)] and Black patients [1.31 (1.23,1.40)] were in the low adherence group.</a></p> <p><b>Conclusions </b>In a large population of older patients with type 2 diabetes, 45% were highly adherent during the first year of SGLT2i<b> </b>treatment. Female sex and Black race/ethnicity were most strongly associated with low adherence. </p>