Abstract
BACKGROUND: Medication adherence is an indispensable prerequisite for the long-term management of many chronic diseases. However, published literature suggests that non-adherence is widely prevalent. Health behavior change theories can help understand the underlying processes and allow the accumulation of knowledge in the field. The present study applied the health action process approach (HAPA) in an intensive longitudinal research design to investigate medication adherence in patients after discharge from inpatient cardiac rehabilitation.
METHOD: In total, n = 139 patients (84.9% male, M$_{age}$ = 62.2 years) completed n = 2,699 daily diaries in the 22 days following discharge from inpatient cardiac rehabilitation. Patients' intentions to take medication and predictors were assessed in daily end-of-day questionnaires. Adherence to medication was measured subjectively (self-report) and objectively. Multilevel modeling was applied to disentangle the between- and within-person level.
RESULTS: Higher levels of risk awareness and self-efficacy were positively associated with intentions to take medication at both levels of analysis. Contrary to theoretical assumptions, positive outcome expectations were not associated with intention, neither between- nor within-person. In contrast to published literature, patients showed very high medication adherence (95.2% self-report, 92.2% objectively).
CONCLUSION: In line with the theoretical assumptions, the results showed that risk awareness and self-efficacy are promising modifiable factors that could be targeted to motivate patients to take medication as prescribed. Daily measurements revealed that patients took their medication as prescribed; thus, future studies should make every effort to recruit patients vulnerable to non-adherence to avoid ceiling effects.
Bierbauer, Walter