Outpatient Hypertension Control and Prescribing Habits for Hypertension in Taiwan

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.

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.

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.

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.

Combination therapy; Hypertension control rate; Prescribing habit.