Evaluating Adherence and Health Outcomes among Patients on Concomitant Diabetes, Hypertension, & Hyperlipidemia Treatments Using Marginal Structural Modeling

Objective: Diabetes, hypertension, and hyperlipidemia have been identified as common modifiable risk factors of CVD, frequently occurring together, especially among the elderly. Medication adherence to concomitant triple therapy is of vital importance among this population. The objective of the current study was to examine adherence to concurrent oral antidiabetics, RAS antagonists, and statins (triple therapy) and evaluate the association between adherence to concomitant triple therapy and intermediate outcomes as well as cardiovascular outcomes among older adults under managed care. Methods: A retrospective cohort study with patients on concurrent triple therapy was conducted using a Texas Medicare Advantage database from January 2016 until December 2019. Medication adherence was measured using PDC during the follow-up periods to determine different adherence groups. A1C, LDL-C control and CV outcomes were also measured every 6 months. A multinomial logistic regression was conducted to determine various demographic and clinical factors associated with each adherence group. Lastly, a marginal structural model controlling for baseline covariates and time-varying confounders affected by prior adherence was conducted to evaluate the association. Results: For aim 1 the final patient cohort was comprised of 7,847 patients. Of these 68.05% of patients were adherent to triple therapy, 21.43% of patients were adherent to double therapy and 10.51% of patients were adherent to monotherapy/none. Several socio-demographic and clinical predictors were associated with the different adherence groups. For aim 2, patients who were adherent to triple therapy and double therapy were more likely to have their LDL-C as well as A1C under control as compared to patient’s adherent to monotherapy/none. For aim 3, there was no significant associations between adherence to triple/double therapies and cardiovascular outcomes. Conclusion: Adherence to triple therapy among the elderly was sub-optimal. The study demonstrated the beneficial effects of adherence to concurrent oral antidiabetics, statins, and RAS antagonists among older adults in a real-world setting. Future studies should evaluate the association between adherence to triple therapy and CV outcomes using longer follow-up periods.