| Blood
pressure reduction in older patients with systolic hypertension may
decrease risk for dementia Older patients with systolic hypertension who took antihypertensive therapy for a median time of 3.9 years had a reduced incidence of new-onset dementia, according to an article in the October 14th issue of The Archives of Internal Medicine. According to background information cited in the article, hypertension is associated with an increased risk for vascular dementia and Alzheimer disease. In the Systolic Hypertension in Europe trial, researchers found that patients with high systolic blood pressure (systolic 160 to 219 mm Hg with diastolic below 95 mm Hg) who took antihypertensive medication had a 50 percent lower incidence of dementia than did patients in the control group, which received placebo (7.7 versus 3.8 cases per 1,000 patient years). That study was stopped in 1997 because of emerging data on the benefits of taking antihypertensive medications to prevent stroke. In the current study, Jan A. Staessen, M.D., Ph.D., and his Belgian colleagues evaluated 2,902 patients from the earlier study who had no dementia and were at least 60 years old at baseline. After the earlier study ended, patients randomized to the active treatment group continued to receive antihypertensive therapy and were told the identity of their study group (treatment or placebo). Treatment consisted of nitrendipine (10 - 40 mg/day), with the possible addition of other antihypertensive drugs, enalapril, hydrochlorothiazide, or both. Patients originally assigned to the placebo group were offered the same antihypertensive therapy with doses adjusted based on blood pressure level and response. The follow up of participants was extended from a median of 2 years from the first part of the earlier study to 3.9 years overall. Blood pressure was 7.0/3.2 mm Hg higher in the 1,417 patients originally assigned to the control group than in the 1,485 patients originally assigned to antihypertensive therapy. Patients who received longer-term antihypertensive therapy reduced their risk of dementia by 55 percent (from 7.4 to 3.3 cases per 1,000 patients per year). During the study period, there were 64 cases of dementia (41 cases of Alzheimer disease): 43 in the original control group and 21 in the original active treatment group. The authors suggest that long-term antihypertensive
treatment caused the decreased incidence of dementia, and ---because
dementia is a leading cause of disability worldwide--- their findings
may have important public health consequences. |