Lowered risks of hypertension and cerebrovascular disease after vitamin/mineral supplementation: the Linxian Nutrition Intervention Trial

Abstract

A total of 3,318 men and women from a region in rural China were randomized to receive daily either a multiple vitamin/mineral supplement or a placebo. Deaths that occurred in the participants were ascertained and classified according to cause over the 6-year period from 1985 to 1991. At the end of supplementation, blood pressure readings were taken, and the prevalence of hypertension was determined. There was a slight reduction in overall mortality in the supplement group (relative risk (RR) = 0.93, 95 percent confidence interval (CI) 0.75-1.16), with the decreased relative risk most pronounced for cerebrovascular disease deaths (RR = 0.63, 95 percent CI 0.37-1.07). This benefit was greater for men (RR = 0.42, 95 percent CI 0.19-0.93) than for women (RR = 0.93, 95 percent CI 0.44-1.98). Among the survivors, the presence of elevations in both systolic and diastolic blood pressures was less common in those who received the supplement (RR for men = 0.43, 95% CI 0.28-0.65; RR for women = 0.92, 95 percent CI 0.68-1.24). This study indicates that supplementation with a multivitamin/mineral combination may have reduced mortality from cerebrovascular disease and the prevalence of hypertension in this rural population with a micronutrient-poor diet.