The association between physician's affiliation and patients' adherence to their antihypertensive medication and pharmaceutical knowledge.

Background: The aim of this study was to examine whether or not the type of physician is associated with the knowledge of and adherence to hypertensive medication among patients.

Methods: The study was a self-administered questionnaire survey among patients who submitted their prescriptions for antihypertensive drugs to 13 pharmacies in Japan in 2006. We compared patients' knowledge of their medications and the self-reported adherence according to the type of physician.

Results: A total of 736 patients were surveyed, and 687 (362 from clinics and 325 from hospitals) were analyzed. In total, 51.8% of the patients correctly named their antihypertensive medicine, with no significant differences observed between clinics and hospitals (51.4% in clinics vs 52.3% in hospitals;  = 0.81, adjusted odds ratio (OR) to the hospital: 0.736, 95% confidence interval [CI]: 0.50-1.08). Significant differences were not observed in the knowledge of the frequency with which hypertensive medication was supposed to be taken (47.2% in clinics vs 46.5% in hospitals;  = 0.84, adjusted OR: 0.80, 95% CI: 0.55-1.16), nor observed in the knowledge of the side effects of the medication (53.2% in clinics vs 51.0% in hospitals;  = 0.57, adjusted OR: 1.14, 95% CI: 0.78-1.68). No significant difference was observed in self-reported adherence (75.1% in clinics vs 77.7% in hospitals;  = 0.42, adjusted OR: 0.73, 95% CI: 0.46-1.16).

Conclusions: About 75% answered that they were taking their medication as instructed. No significant differences were observed in responses based on the physician's affiliation. Further studies are needed to achieve better patient's adherence and pharmaceutical knowledge.