Normal blood pressure in patients with insulinoma despite hyperinsulinemia and insulin resistance.

This article examines the relationship between blood pressure and serum insulin patients with endogenous hyperinsulinemia due to insulinomas. The hypothesis that hyperinsulinemia is an independent causal factor in the development of essential hypertension in this patient population was investigated. Inappropriately high plasma concentrations of insulin and proinsulin were found in these patients; however, their blood pressure levels did not differ from those of normal control subjects. Moreover, the surgical removal of the insulinomas did not reduce their blood pressure. Therefore, these findings argue against the hypothesis that hyperinsulinemia is an independent causal factor in the development of essential hypertension in humans.