Illness Perceptions, Self-efficacy, and Self-reported Medication Adherence in Persons Aged 50 and Older With Type 2...

Illness perceptions, patients' beliefs about their health condition, may affect medication adherence as well as self-efficacy for managing the condition in type 2 diabetes (T2DM).

The aims of this study were to investigate the associations between illness perceptions, self-efficacy, and self-reported medication adherence among persons (≥50 years of age) with T2DM and explore whether the number of comorbid conditions moderates these associations.

This secondary analysis of cross-sectional data used baseline data from persons with T2DM. Self-administered questionnaires, including the Brief Illness Perception Questionnaire, Self-efficacy for Managing Chronic Disease, and the 4-item Morisky-Green-Levine Medication Adherence Scale, were used. We performed hierarchical multiple linear regression analyses.

Participants (N = 146) were 57.5% female, 67.1% white, and on average 64 years old. Six dimensions of illness perceptions (ie, consequences, personal control, treatment control, identity, concerns, and emotional representations) were associated with self-efficacy for managing T2DM. Five dimensions (ie, timeline, personal control, treatment control, coherence, and emotional representations) were significant predictors of self-reported medication adherence. Whereas the number of comorbid conditions was significantly associated with self-efficacy for managing T2DM in all models (P values < .001), the number of comorbid conditions was not associated with self-reported medication adherence.

This study suggests that illness perceptions and comorbid conditions may play a critical role in either self-efficacy or self-reported medication adherence in persons (≥50 years of age) with T2DM. Future research should incorporate an individual's illness perceptions and comorbid conditions into the development of interventions that may improve both self-efficacy and medication adherence in T2DM.