The relationship of sodium sensitivity to insulin resistance

Substantial epidemiologic evidence has indirectly implicated sodium intake in the pathogenesis of hypertension. The concept of sodium-sensitivity as a cause of essential hypertension has been addressed by many investigators, yet the pathogenesis of this salt-sensitivity remains unclear. Although not well appreciated, most studies have shown that regardless of sodium intake or the presence or absence of hypertension, sodium-sensitive subjects tend to weigh more than sodium-resistant subjects. Insulin-resistance has been postulated to be responsible for enhanced sodium retention in obese individuals; therefore, insulin-resistance may be critical to the pathogenesis of sodium-sensitivity in individuals with essential hypertension. This article summarizes the data relating insulin and or insulin-resistance to sodium sensitivity in obesity, diabetes, and in non-obese subjects with essential hypertension.