Factors Related to Medication Adherence of Cognitively Impaired Patients in Community Pharmacies

Objective: The objective of the study was to identify factors related to donepezil medication adherence ("adherence") of cognitively impaired patients in community pharmacies. Methods: One hundred and twenty community pharmacies in 28 regions in Japan were randomly selected. Questionnaires were mailed to these pharmacies. The pharmacists answered based on the medication profiles ("YAKUREKI") of the patients given donepezil at their pharmacies. The survey items were "adherence", "who is the key person" and ‘the key person’s understanding and awareness of donepazil and its symptoms. The χ2 test and decision tree modeling analysis were performed to examine factors affecting adherence. A 5% level of statistical significance was used in the χ2 test. Results: Questionnaires with data on 479 patients were returned. The most common level of adherence was “take as instructed” (81.2%), followed by “forget once or twice a week” (10.2%). The χ2 test revealed that adherence was good if "key person" was professional caretaker (P = 0.004). Also, adherence was better if key person understood medication about dosage, P < 0.001; effect, P = 0.002; and general side effects,, P < 0.001. According to decision tree analysis, the key person had the strongest relationship with adherence. Conclusions: It was confirmed that the key person’s understanding of the medication and symptoms of cognitive impairment are related to adherence. In particular, it was suggested that there is a strong relationship between the key person and adherence and that factors related to adherence differ according to who the key person is. It is essential in the treatment of cognitive impairment to accurately identify the "key person", in order to provide better pharmaceutical care in community pharmacies.