Dietary sodium intake and incidence of congestive heart failure in overweight US men and women - First National Health and Nutrition Examination Survey Epidemiologic Follow-up Study

Background: Cross-sectional epidemiologic studies suggest that a higher intake of dietary sodium is associated with an increased risk of left ventricular hypertrophy. We studied the relationship between dietary sodium intake and incidence of congestive heart failure (CHF) in the first National Health and Nutrition Examination Survey Epidemiologic Follow-up Study participants. Participants and Methods: The study sample consisted of 5233 nonoverweight and 5129 overweight men and women without a history of CHF at their baseline examination. Dietary sodium and other nutrient intake estimates were obtained by a 24-hour dietary recall method at the baseline examination, conducted from 1971 to 1975. The incidence of CHF was assessed using medical records and death certificates obtained in 1982 to 1984, 1986, 1987, and 1992. Results: During an average og 19 years of follow-up we documented 413 case of CHF in nonoverweight and 679 cases of CHF in overweight participants. After adjustment for known CHF risk factors, the relative risk of CHF among overweight participants was 1.43 (95% confidence interval, 1.07-1.91) for those whose sodium intake was greater than 113.6 mmol/d compared with those whose intake was less than 50.2 mmol/d. The relative risks of CHF for a 100-mmol/d higher intake of sodium or per 1743 kcal (average energy intake in the study population) were 1.26 (95% confidence interval, 1.03-1.53) and 1.21 (95% confidence interval, 1.04-1.40), respectively. Conclusions: A higher intake of dietary sodium is a strong independent risk factor for CHF in overweight persons. A reduction in sodium intake may play an important role in the prevention of CHF in overweight individuals and populations.