International multicentre study of indapamide in the treatment of essential arterial hypertension.

A total of 1600 patients with essential arterial hypertension was recruited from 10 countries, and treated with indapamide according to a common protocol. 703 subjects who completed the protocol were analysed, from whom 644 were followed for 3 months, and the remainder (all from Belgium) up to 10 months. The group of 644 showed a highly significant drop in erect and supine blood pressures after one month, and this was maintained after 3 months treatment. The percentage of responders (normalization of diastolic pressure, or drop of at least 30 mmHg) was 64% after 3 months. The Belgian group maintained their reductions in pressure at 6 and 10 months. Serum potassium showed a modest drop, but remained within normal limits: other biochemical values were virtually unchanged. Some side effects were noted, but none was serious. It is concluded that indapamide is a first line treatment for essential arterial hypertension.