Characteristics of Antihypertensive Medication and Change of Prescription Over 1 Year of Follow Up in Japan: Fukushima Research of Hypertension (FRESH)

BACKGROUND: The relationship between achieving target blood pressures and medication modification among hypertensive patients in Japan is relatively unknown. We examined the incidence of prescription changes and how the prescription changes influence success rates in achieving target blood pressures in a group of patients with uncontrolled hypertension. METHODS: This prospective observational cohort study (July 2006 to May 2007) examined the association between blood pressure control and antihypertensive medication among 2,735 Japanese hypertensive patients who completed four seasonal follow-ups and whose medications were verified. The primary outcome was "therapeutic failure" at the third follow-up survey. Logistic regression analyzed how prescription changes may influence therapeutic failure risk. Common medication changes were estimated using follow-up data. RESULTS: Median ages and proportion of males were 73 years and 43.8% vs. 69 years and 45.6% in those with controlled and those with uncontrolled hypertension at baseline, respectively. At baseline, 1,496 patients were uncontrolled, and 296 (18.0%) changed prescriptions during the follow-up period. Among patients with diabetes mellitus, renal disease, or organ damage and vascular complications, who were uncontrolled at baseline, prescription changes during the year significantly increased therapeutic failures at the third follow-up after adjusting for related variables. About half of the changes at each follow-up visit remained in the same class or combination category. CONCLUSIONS: This study identified infrequent changes in prescription and minor modifications of medication even among uncontrolled hypertension. We highlight the importance of reviewing prescription content to maintain or improve blood pressure levels to achieve recommended treatment goals.