Low dosages of felodipine ER once daily as monotherapy in elderly hypertensive patients: effect on ambulatory blood pressure and quality of life

OBJECTIVE: To establish the efficacy of 24-h ambulatory and casual blood pressure (BP) reduction, and the tolerability of once daily felodipine extended release (ER) 2.5 mg and felodipine ER 5 mg as monotherapy. DESIGN: Randomised, double-blind placebo controlled 6 weeks parallel study. SETTING: From 15 general practices centres (with 19 GPs) in the region of the University of Maastricht, The Netherlands. SUBJECTS: A total of 129 subjects aged 50-80 years with primary hypertension were screened; 27 men and 61 women with a casual diastolic BP of 100-115 mm Hg and/or a systolic BP of less than 200 mm Hg entered the study. MAIN OUTCOME MEASURES: Casual and 24-h ambulatory BP and a subjective symptom assessment (SSA) questionnaire after 6 weeks of therapy. RESULTS: After correlation for placebo response the mean casual systolic/diastolic BP (SBP/DBP) reduction was 10/5 mm Hg (NS) and 12/10 mm Hg (P < 0.05) for felodipine ER 2.5 and 5 mg, respectively. By using 24-h ambulatory BP measurements these reduction were 6/4 mm Hg (NS) and 13/8 mm Hg (P < 0.05), respectively. No significant difference for SBP and DBP was found during the night time between felodipine 2.5 and placebo (-1/0). Felodipine ER 5 mg lowered the BP load significantly during both daytime and night time but felodipine ER 2.5 mg only for DBP during the daytime. There was a significant difference for the number of responders between placebo (28%) vs felodipine ER 2.5 mg (55%) and ER 5.0 mg (59%). Both felodipine dosages and placebo were comparable in (a low) number of adverse events and results of the SSA. CONCLUSIONS: During daytime felodipine ER 2.5 mg and 5 mg are effective in BP lowering in elderly hypertensive patients. However, only felodipine ER mg is effective in reducing BP during night time (22.00-7.00). Only felodipine ER 5 mg has a significant reducing effect on BP load during day and night time. Both felodipine ER 2.5 and ER 5.0 have a significant effect on the responder rate. It appeared from this study that compared to placebo, and in contrast with felodipine ER 5 mg, the ER form of felodipine 2.5 mg has no BP lowering effect during night time in elderly patients. To assess the effectivity during night time of felodipine ER 2.5 mg in an individual patient it is recommendable to measure the BP at the end of the dose interval.