Background: The beneficial effects of potassium-enriched salt on blood pressure have been reported in a few short-term trials. The long-term effects of potassium-enriched salt on cardiovascular mortality have not been carefully studied.
Objective: The objective was to examine the effects of potassium-enriched salt on cardiovascular disease (CVD) mortality and medical expenditures in elderly veterans.
Design: Five kitchens of a veteran retirement home were randomized into 2 groups (experimental or control) and veterans assigned to those kitchens were given either potassium-enriched salt (experimental group) or regular salt (control group) for approximately 31 mo. Information on death, health insurance claims, and dates that veterans moved in or out of the home was gathered.
Results: Altogether, 1981 veterans, 768 in the experimental [x (+/-SD) age: 74.8 +/- 7.1 y] and 1213 in the control (age: 74.9 +/- 6.7 y) groups, were included in the analysis. The experimental group had better CVD survivorship than did the control group. The incidence of CVD-related deaths was 13.1 per 1000 persons (27 deaths in 2057 person-years) and 20.5 per 1000 (66 deaths in 3218 person-years) for the experimental and control groups, respectively. A significant reduction in CVD mortality (age-adjusted hazard ratio: 0.59; 95% CI: 0.37, 0.95) was observed in the experimental group. Persons in the experimental group lived 0.3-0.90 y longer and spent significantly less (approximately US Dollars 426/y) in inpatient care for CVD than did the control group, after control for age and previous hospitalization expenditures.
Conclusions: This study showed a long-term beneficial effect on CVD mortality and medical expenditure associated with a switch from regular salt to potassium-enriched salt in a group of elderly veterans. The effect was likely due to a major increase in potassium and a moderate reduction in sodium intakes.