901–114 Women Have a Higher Response Rate than Men to the Antihypertensive Calcium Channel Blocker Amlodipine

Abstract

There is a lack of data on gender difference in response to the newer antihypertensive medicines. The Amlodipine Cardiovascular Community Trial was designed to determine the blood pressure (BP) response of patient subgroups with mild-moderate hypertension to amlodipine besylate monotherapy (5–10 mg/day). After a 2 week placebo phase, patients received amlodipine for a 4 week efficacy/titration phase followed by a 12 week maintenance phase. Goal BP was defined as a decrease in diastolic BP by 10 mmHg or more plus a diastolic BP of less than 90 mmHg. Baseline systolic BP in mmHg was 153 ± 16 and 155 ± 16 and diastolic BP 101 ± 4 and 100 ± 4 for males (n = 702) and females (n = 382), respectively. Decreases in BP at 4 weeks were greater in females than males for both systolic (-19 vs -15 mmHg, p < 0.0001) and diastolic BP (-14 vs -12 mmHg, p < 0.0001). Results were maintained at 12 weeks. Ninety-one percent of females achieved goal BP compared to 83% of men (p = 0.001). The greater response to amlodipine by women remained significant after adjusting for: age, weight, dose (mg/kg), baseline BP. and drug compliance (99% in both women and men). There was no difference in decrease in systolic and diastolic BP for women on hormone replacement (–18 and–14 mmHg) versus those not on hormone replacement (–19 and–14 mmHg). Thus, hormone replacement in women did not account for the gender difference in BP response. Women reported edema more frequently than men. In conclusion, women demonstrated a greater antihypertensive effect to amlodipine than men; the mechanism for this observation remains to be determined.