Hyperinsulinaemia, insulin resistance, microalbuminuria and the risk of coronary heart disease.

In population studies both hyperinsulinaemia, a marker for insulin resistance, and microalbuminuria have been shown to predict coronary heart disease. Insulin resistance clusters with several standard cardiovascular risk factors, as well as with abnormalities of fibrinolysis, with small, dense, low-density lipoprotein patterns, and with elevated concentrations of proinsulin-like molecules. This makes the independence of the relationship with coronary heart disease difficult to disentangle. Microalbuminuria is associated with a number of abnormalities of risk factors, but the relationship with coronary heart disease does not appear to be explained by these associations. The two conditions, insulin resistance and microalbuminuria, are associated, and together appear to be a very powerful predictor of cardiovascular risk. There is evidence that endothelial dysfunction may lead to impaired insulin action, as well as to capillary albumin leak, and the proposal is made that these associations, with each other and with coronary heart disease, are features of a common antecedent. The role of growth retardation in endothelial function, and in determining cardiovascular risk in adulthood is a subject of intense interest.