Co-occurring reasons for medication nonadherence within subgroups of patients with hyperlipidemia
Medication nonadherence is a significant clinical problem among individuals taking statins. Poor adherence is often attributable to several reasons, yet most adherence interventions target a single reason. Baseline data were examined from a randomized clinical trial of 236 patients with hyperlipidemia. A latent class analysis was then performed on patients reporting any nonadherence (n = 109). A 4-class solution provided the most optimal fit and differentiation of classes. Class 1 (N = 59, 54%) included patients who reported occasionally forgetting. Class 2 (N = 16, 14%) represented patients who were concerned about side effects. Class 3 (N = 17, 16%) represented patients who reported out-of-routine life events as contributing to nonadherence. Class 4 (N = 17, 16%) represented patients who endorsed a large number reasons indiscriminately. Class membership was almost uniformly unrelated to any patient demographic factors or treatment arm. Each cluster of reasons defining these patients may be best addressed through different intervention strategies.
KeywordsMedication nonadherence Self-report Latent class analysis Reasons
Dr. Blalock was supported by Grant No. TPH 21-000 from the Department of Veterans Affairs Office of Academic Affiliations. Drs. Bosworth and Voils are supported by VA HSR&D Research Career Scientist (RCS) Awards (RCS 08-027 and RCS 14-443, respectively). The study was funded by a VA HSRD grant to Dr. Bosworth (IIR 08-297). This work was also supported by the Center of Innovation for Health Services Research in Primary Care (CIN 13-410) at the Durham VA Medical Center. We thank Felicia McCant, MSW and Susanne Danus, BS for their administrative support.
Compliance with ethical standards
Conflict of interest
Dan V. Blalock, Hayden B. Bosworth, Bryce B. Reeve and Corrine I. Voils declare that they have no conflict of interest.
Human and animal rights and Informed consent
All procedures followed were in accordance with ethical standards of the responsible committee on human experimentation (institutional and national) and with the Helsinki Declaration of 1975, as revised in 2000. Informed consent was obtained from all patients for being included in the study.
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