Chlorthalidone treatment increased life expectancy of test patients with hypertension

January 13, 2012

The results of a long-term follow-up of chlorthalidone stepped-care therapy for isolated systolic hypertension demonstrated that the treatment is associated with a longer life expectancy.

The results of a long-term follow-up of chlorthalidone stepped-care therapy for isolated systolic hypertension demonstrated that the treatment is associated with a longer life expectancy.

The study was published in the December 21, 2011, issue of the Journal of the American Medical Association. It reported data from a 22-year follow-up of participants in the Systolic Hypertension in the Elderly Program (SHEP) trial, which was conducted between March 1985 and January 1988.

John B. Kostis, MD, of the Cardiovascular Institute, UMDNJ-Robert Wood Johnson Medical School, New Brunswick, NJ, and colleagues obtained the long-term mortality data to examine whether the effect of blood-pressure (BP) lowering was associated with long-term outcomes and extended life expectancy.

“The goal of our study was to describe cardiovascular death and all-cause mortality of the SHEP trial 22 years after the beginning of randomization,” the authors wrote.

The SHEP trial enrolled men and women aged 60 years or older who had isolated systolic hypertension. It was designed to assess the effect of antihypertensive drug treatment in reducing the risk of stroke in these patients.

A total of 4,736 patients were randomly assigned to active treatment therapy (2,365) with chlorthalidone, and atenolol if antihypertensive control was not sufficient, or to placebo (2,371) for 4.5 years.  After that time all participants were asked to begin active therapy.

At the 22-year follow-up, life expectancy gain between active therapy and placebo survival was 105 days (95% CI, -39–242; P=.07) for all-cause mortality and 158 days (95% CI, 36–287; P=.009) for cardiovascular death, corresponding with a 1-day (0.89 days; 95% CI, 0.20–1.62) gain in life expectancy for each month of active treatment.

“This gain in life expectancy is important, because it occurred among persons with a mean age of 72 years at baseline,” the authors wrote, concluding that active treatment each month was associated with an additional day free from risk of cardiovascular death.