Randomised controlled trial to examine the e V ects of a GP exercise referral programme in Hailsham , East Sussex , on modifiable coronary heart disease risk factors
Objective—To examine the eVects of a GP exercise referral programme on modifiable coronary heart disease risk factors. Design—Randomised controlled trial. A battery of validated measures were carried out at 0, 8, 16, 26, and 37 weeks. Setting—Two community health centres and a leisure centre in Hailsham, East Sussex. Subjects—389 patients (smokers, hypertensive or overweight) were selected from medical records, screened for contraindications to exercise and 345 were invited into the study. Of 142 patients randomly allocated, 40 (41%) completed the study in the exercise group and 31 (69%) in the control group. Sixty (35%) invited smokers (48% of non-smokers), 71 (38%) invited hypertensive patients (45% of non-hypertensive patients), and 107 (45%) overweight patients (33% of non-overweight patients) were randomised. Of those randomised, 27 (45%) smokers, 52 (48%) overweight, and 43 (61%) hypertensive patients completed the study. Intervention—The exercise group was oVered 20, half price sessions over 10 weeks at a leisure centre. Patients engaged in moderate and vigorous aerobic type activity on various exercise machines, in a semi-supervised, informal environment. Results—87% of those referred used the prescription and 28% (high adherers)(45% of obese patients) did at least 15 sessions. The exercise group reduced sum of skinfolds by 8.1% (2.9 to 13.3, 95% confidence intervals) more than the control group, up to 16 weeks after baseline. High adherers reduced sum of skinfolds by 9.2% (0.9 to 17.5) more than the control group, up to 26 weeks. High adherers reduced systolic blood pressure by 7.2% (−0.7 to 14.9) (that is, 9 mm Hg) more than low adherers, up to 37 weeks. Non-smokers and obese patients attended more prescribed sessions than smokers and non-overweight patients. Conclusions—Reduction in sum of skinfolds was maintained up to 26 weeks, among high adherers compared with controls. Reduction in systolic blood pressure was evident up to 37 weeks among high adherers, but only in comparison with low adherers. Selection of appropriate referees and use of other strategies to improve exercise adherence will help to maximise the benefits from GP exercise prescription schemes. (J Epidemiol Community Health 1998;52:595–601) Physical inactivity has been identified as an endemic coronary heart disease (CHD) risk factor.Increasing physical activity in the population may also modify other risk factors such as body fat and hypertension. For example, in a review, net changes in systolic blood pressure, associated with endurance training, were reported to be −6.2, and −9.9 mm Hg among borderline hypertensive and hypertensive patients, respectively. A growing interest has emerged in the promotion of physical activity through primary health care. 8 Many schemes involve GPs referring patients to leisure centre based exercise programmes. However, some scepticism is held by health service managers and others about the eVectiveness of a programme of prescribed exercise for chronic health problems. Such schemes have not previously been rigorously evaluated in the UK. The purpose of this randomised controlled study was therefore to evaluate a fully operational GP referral scheme, in terms of modifying physical activity, blood pressure, smoking, and body composition over a nine month period.