Background: Hypertension control is of the utmost importance for reducing cardiovascular risk. In Taiwan, the hypertension control rate of the general population is low (25%). We investigated the factors affecting outpatient hypertension control to determine whether the low control rate stems from clinician unawareness or inadequate public education.
Methods: Hypertensive patients were recruited between 2003 and 2004 by 13 cardiologists and 9 non-cardiologists from 19 hospitals distributed across four geographical areas of Taiwan. Each clinician recruited 100 consecutive patients from outpatient clinics and reported their drug prescriptions, co-morbidities, and blood pressure (BP) levels. Data were analyzed using the chi square test and multivariate logistic regression analyses.
Results: Of the 2145 enrolled patients, 63% attained the BP goal of < 140/90 mmHg. BP control rates were higher in older patients, and in patients who were treated by cardiologists and at medical centers. The control rate of high risk co-morbidity patients (BP goal of < 130/80 mmHg) was 36%, which was significantly lower than the 62% control rate of low risk patients (BP goal of < 140/90 mmHg). Cardiologists achieved higher BP control rates (65% vs. 60%; p = 0.0039), and prescribed more combination regimens (p < 0.0001) and beta blockers than non-cardiologists. Overall, 63% of patients received combination therapy. Calcium channel blockers were the most commonly prescribed antihypertensive drugs, followed by beta blockers, angiotensin receptor blockers, diuretics, and angiotensin-converting enzyme inhibitors.
Conclusions: Two-thirds of the entire study population received combination therapy, although BP control rate is still less than optimal in the high risk patients. Ultimately, a more aggressive strategy is strongly encouraged for patients considered to be at high risk.
Key words: Combination therapy; Hypertension control rate; Prescribing habit.