HYPERTENSION IN DIABETES STUDY .4. THERAPEUTIC REQUIREMENTS TO MAINTAIN TIGHT BLOOD-PRESSURE

We report the efficacy of therapy over 5 years follow-up in 758 non-in sulin-dependent diabetic patients in a prospective, randomised control led study of therapy of mild hypertension. Patients were recruited who on antihypertensive therapy had systolic blood pressure over 150 mmHg or diastolic over 85 mmHg, or if not on therapy had systolic blood pr essure over 160 mmHg or diastolic over 90 mmHg. Their mean blood press ure at entry to the study was 160/94 mmHg at a mean age of 57 years. T hey were allocated to tight control (aiming for systolic < 150/diastol ic < 85 mmHg) or to less tight control (aiming for systolic < 180/dias tolic < 105 mmHg). The tight control group were allocated to primary t herapy either with a beta blocker (atenolol) or with an antiotensin co nverting enzyme inhibitor (captopril), with addition of other agents a s required. Over 5 years, the mean blood pressure in the tight control group was significantly lower (143/82 vs 154/88 mmHg, p < 0.001). No difference was seen between those allocated to atenolol or captopril. The proportion of patients requiring three or more antihypertensive th erapies to maintain tight control in those allocated to atenolol or ca ptopril increased from 16 and 15 %, respectively at 2 years to 25 and 26 %, respectively at 5 years, whereas in the less tight control group at 2 and 5 years only 5 and 7 %, respectively required three or more therapies. There was no difference in the incidence of side effects or hypoglycaemic episodes between those allocated to atenolol or captopr il, but those allocated to atenolol increased their body weight by a m ean of 2.3 kg compared with 0.5 kg in those allocated to captopril (p < 0.01). Allocation to atenolol was also associated with small increas es in triglyceride, and decreases in LDL and HDL cholesterol, which ar e of uncertain clinical relevance. The study is continuing to determin e whether the improved blood pressure control, which was obtained, wil l be beneficial in maintaining the health of patients by decreasing th e incidence of major clinical complications, principally myocardial in farction and strokes, and microvascular complications, such as severe retinopathy requiring photocoagulation and deterioration of renal func tion.