The Swedish Trial in old patients with hypertension-2 (STOP-hypertension-2): a progress report

The Swedish Trial in Old Patients with Hypertension-2 (STOP-Hypertension-2) was designed by a project group of the Swedish Hypertension Society to test whether the "newer" treatment alternatives (ACE inhibitors and calcium antagonists) are as good as, better or less good than, the "older" ones (beta-blockers and diuretics) in terms of preventing cardiovascular morbidity and mortality in elderly hypertensives. The aim of the present paper is to report on the progress of the study.

Prospective, open trial with blinded end-point committee and centralized randomization (PROBE design). STOP-Hypertension-2 may be regarded as a scientific follow-up of the previously published Swedish Trial in Old Patients with Hypertension (STOP-Hypertensioon-1) (6) using the same study organization.

By the end of 1994 when recruitment was stopped, 6628 hypertensive men (34%) and women (66%) aged 70-84 (mean age 76) had been included at 312 Swedish health centres (out of approximately 850). In the whole cohort 11% are diabetics and 9% smokers. The mean total cholesterol value is 6.5 mmol/L.

In the whole study cohort, blood pressure was lowered from 194/98 mmHg to 167/85 mmHg after one year. At the end of 1995, 319 fatal events (all-cause mortality) had been reported, corresponding to a mortality rate of 21.3 per 1000 person-years.

In STOP-Hypertension-2, 6628 elderly hypertensive have been randomized to three different treatment regimes: beta-blocker+diuretics (the active treatment arm in STOP-Hypertension-1), ACE inhibitors, or calcium antagonists. Their average lowering of blood pressure was 27/13 mmHg and end-points have occurred at the expected rate. Thus, it should be possible to terminate STOP-Hypertension-2 within two to three years.