PS-C10-9: EFFECTIVENESS OF AMLODIPINE ON 24-HOUR AMBULATORY BLOOD PRESSURE IN ADULT PATIENTS WITH MILD-MODERATE ESSENTIAL HYPERTENSION: A MULTICENTRE OBSERVATIONAL, REAL-WORLD STUDY

Abstract

Objective: Inadequate 24-hour blood pressure control could cause complications, especially in high-risk hypertensive individuals. Hence, it is recommended that the targeted blood pressure levels be maintained round the clock. This prospective, observational study assessed the 24-hour ambulatory blood pressure (ABP) control with 8-week amlodipine therapy 5/10 mg/day in patients with hypertension. Methods: Adult patients (62 m, 42 f) with mild-to-moderate essential hypertension received oral amlodipine 5 mg/day (n = 68) or 10 mg/day (n = 36) for 8 weeks. The study was approved by the independent ethics committee and informed consent was obtained from all participants. Primary outcome was change at 8 weeks from baseline in mean 24-hr ABP (systolic and diastolic), and secondary outcomes were change from baseline in mean morning, daytime, night-time, and last 6-hr dosing interval ABP. A repeat measures analysis of covariance (ANCOVA) was done for changes in ABP over 8 weeks, with age, gender, BMI and associated comorbidities as covariates. Nocturnal dippers were assessed as those greater than or equal to 10% reduction in ABP at 8 weeks. Sub-groups were created based on age, duration of hypertension, occupation, baseline BMI and amlodipine dose. Safety was evaluated based on clinical adverse events and 12-lead electrocardiogram. Results: Of the 104 patients from 2 study centers, 49 completed 8-weeks therapy and were included for per-protocol analysis. Significant reductions in the mean 24-hr blood pressure were seen for both SBP and DBP (figure 1). The mean 24-hr. reduction was -10.82 and -6.25 mmHg with 5 mg amlodipine and -19.81 and -11.19 mmHg with 10 mg amlodipine for SBP and DBP respectively (p < 0.0001). The mean morning, daytime, night-time, and last 6-hr reductions in SBP were -14.06, -18.63, -20.42, and -13.51 respectively (p < 0.0001), and DBP reductions were -7.78, -10.27, -11.07, and -6.44 respectively (p < 0.0001). Significant reduction in ABP was seen in all sub-groups (p < 0.0001). Greater reduction in SBP and DBP were observed in patients with stage-2 hypertension. At baseline, there were 30 (61.2%) non-dippers which decreased to 18 (36.7%) at 8 weeks. At the end of the study, 40% of non-dippers were converted to dippers by Amlodipine, whereas none of the dippers were converted to non-dippers. No adverse effects were reported. Conclusion: Amlodipine significantly reduces the 24-hr. mean morning, daytime, night-time, and last 6-hr. ABP and converted non dippers to dippers in adult patients with mild to moderate essential hypertension. The Study highlights the consistent effects of amlodipine on both quantity and quality of 24 hours BP control which is important for associated CV risk reduction.