RANDOMISED CONTROLLED TRIAL OF MODERATE INTENSITY EXERCISE IN THE TREATMENT OF HYPERTENSION

Abstract

1142 Moderate intensity exercise is prescribed to reduce blood pressure, but its efficacy is unclear. This study investigated the efficacy of a six week programme of home-based, moderate intensity exercise, predominantly walking, in reducing daytime (10am - 10pm) ambulatory blood pressure. Subjects were sedentary adults (72 male, 47.0 (9.6)yr; 18 female, 50.6 (7.6)yr) (mean (s.d.) with baseline blood pressure 150-180mmHg systolic and/or 91-110mmHg diastolic, and not receiving pharmacological therapy for blood pressure control. Intervention subjects performed 30 minutes of moderate intensity exercise, on five out of every seven days, for a period of six weeks. Compliance with the intervention was monitored using accelerometers and activity diaries. Intention to treat analysis, excluding those lost to follow-up (n=4), demonstrated a net difference of −1.8/−2.2mmHg (systolic/diastolic) in intervention vs. control subjects (p=0.31, 95%CI −5.4 to +1.8 systolic; p=0.11, 95%CI −4.9 to +0.05 diastolic) after adjustment for baseline differences in ambulatory blood pressure. Compliance was 89.8% with regard to the number of exercise sessions completed, and mean energy expenditure in the exercise bout was 222.1 (70.7) kcal. No significant changes were found in weight or alcohol and salt consumption. This study identified an apparent net effect of moderate exercise on daytime ambulatory blood pressure that did not reach statistical significance. The prescription of moderate intensity exercise to hypertensive patients in primary care to achieve rapid and large reductions in blood pressure should be applied with caution.