[Systolic hypertension in the elderly: Chinese trial (syst-China). Interim report].

Two thousand and seventy-one elderly isolated systolic hypertensive patients entered the multicenter, randomized, double-blind, placebo-controlled clinical trial (997 in the active treatment group and 1,074 in the placebo). The differences of age, height, weight, sex constituent and baseline blood pressure between active treatment and placebo groups yielded no significances. In the 30-month follow-up period, the systolic and diastolic blood pressure in the active treatment were lower than the placebo group (P < 0.05) since the third month of the trial; the side effects were mild and the compliance of the participants was good (97% of the participants in the active treatment was taking medicine punctually during follow-up period; and 96% of the participants in the placebo group did so as well). The average morbidity of isolated systolic hypertension in our country was 8.10%, and the morbidity in female was higher than that in male, based upon the results of our trial. The present trial is in progress and the final results will not be reported until the end of the trial.