The impact of personal and cultural beliefs on medication adherence of patients with chronic illnesses: a systematic review

BACKGROUND: Patients’ adherence to therapeutic regimes may be influenced by subjective beliefs about chronic conditions. One of the challenges for health professionals in enhancing adherence is taking patients’ understanding into account when giving health advice and/or providing medical treatment. PURPOSE: This review aimed to evaluate the consequent effects of personal and cultural beliefs on medication adherence, in patients with chronic conditions such as hypertension, diabetes mellitus, chronic obstructive pulmonary disease and asthma. METHOD: A systematic review methodology was used. PubMed, CINAHL, EMBASE and PsychINFO, databases were searched for relevant articles. The main terms analyzed were illness perceptions, health beliefs, cultural beliefs, chronic conditions and medication adherence. RESULTS: From 2,646 articles, 127 were retained for further assessment, and finally 25 met the inclusion criteria. A cross-sectional questionnaire survey research design was conducted in all included articles. Of these most (n=22) targeted hypertension or diabetes mellitus. A number of personal and cultural based factors were identified as being associated with adherence to medication regimes — 40% of articles (n=10) examined perception of illness, 20% (n=5) health literacy, 16% (n=4) cultural beliefs, 12% (n=3) self-efficacy, 16% (n=4) spiritual and religious beliefs, as well as 20% (n=5) illness knowledge. Statistically significant associations between medication adherence and these personal and cultural factors were found in 80% (n=20) of the included studies. However, the direction of associations varied between studies depending on the factor that was examined. CONCLUSION: This review has evaluated the impact of personal and cultural factors on medication adherence and highlighted the gaps in literature regarding adherence. Further research is required to fully identify the associations between religious beliefs, control beliefs and illness knowledge and medication adherence.