Pathogenesis and measurement of insulin resistance in hypertension

Because of its association with a constellation of cardiovascular risk factors, insulin resistance has recently emerged as a major clinical disorder. There is therefore an increasing need to accurately assess insulin sensitivity in clinical and epidemiologic studies. The merits of various techniques for measuring insulin action are briefly reviewed. Essential hypertension and insulin resistance appear to be tightly linked; however, the mechanism or mechanisms accounting for this association are not known. Central or intra-abdominal obesity is a particularly strong risk factor for the development of hypertension. The weight of the evidence suggests that hyperinsulinemia per se is not a potent instrumental factor in the development of hypertension. Mechanisms suggesting that insulin resistance independent of hyperinsulinemia may predispose to increased vascular tone are discussed. Conversely, the possibility that essential hypertension could engender insulin resistance is proposed. The link between insulin resistance and hypertension is likely to be complex and multifactorial.