Increased risk of heart failure is associated with chronic habitual hypohydration that elevates serum sodium above 142 mmol/l suggesting lifelong optimal hydration as preventive measure

With increasing prevalence of heart failure (HF) owing to the aging population, identification of preventive measures that delay onset of the disease and their implementation become increasingly important. Recent studies demonstrated that chronic subclinical hypohydration accelerates degenerative changes and increases prevalence of many age-dependent degenerative diseases including heart failure (1). Worldwide surveys find wide differences in habitual water intake between and within countries and substantial prevalence of hypohydration in general population (2). Hypohydration elevates extracellular sodium triggering activation of water conservation mechanisms when serum sodium exceeds a threshold around 142 mmol/l. These adaptive responses include secretion of antidiuretic hormone and activation of the renin angiotensin aldosterone system (3), important contributors to pathogenesis of HF. The purpose of this study was to evaluate whether serum sodium concentration at middle age of 44–66 years as a measure of hydration habits is a significant predictor for left ventricular hypertrophy (LVH) and HF events 25 years later at age of 70–90 years. Data from Atherosclerosis Risk in Communities (ARIC) study were obtained from the BioLINCC data repository. In ARIC study, 15,792 44–66 year-old participants were evaluated over 5 visits spanning 25 years (Figure 1A). Two separate logistic regression models were used in the study, where the dependent variable is diagnosis of LVH and HF at visit 5 (age:70–90 years), and the predictors are serum sodium concentration measured at visits 1 and 2 (age: 44–66 years), age, gender, total cholesterol, glucose, eGFR, BMI, smoking and hypertension statuses. Midlife serum sodium is associated with LVH and HF diagnosis 25 years later at visit 5 both with adjustment for age only (LVH: OR=1.24, 95% CI 1.15–1.34, P<0.001; HF: OR=1.06, 95% CI 1.02–1.10, P=0.006) and in fully adjusted model (LVH: OR=1.20, 95% CI 1.11–1.30, P<0.001; HF: OR=1.11, 95% CI 1.01–1.22, P=0.031) (Figure 1B). Cornell voltage criteria used for LVH diagnosis is elevated in participants with higher serum sodium and demonstrates sharper increase with age indicating accelerated hypertrophic LV remodeling (Figure 1C). These associations are reflected in increased prevalence of HF and LVH in 70–90 year-old participants whose middle age serum sodium exceeded 142 mmol/l (Figure 1D). Habitual life-long hypohydration increases risk to develop LVH and HF. Keeping serum sodium below 142 mmol/l by drinking appropriate amount of liquids may slow down decline in cardiac function and decrease prevalence of HF. Type of funding sources: Other. Main funding source(s): NHLBI Intramural program