The prevalence of hypertension in various age groups of diabetics and its role as a risk factor in juvenileonset insulin-dependent diabetics followed for 40 yr after diagnosis was evaluated. The results show clearly that hypertension is more prevalent in diabetics of any age after age 24 yr than in the general population.

In this type of diabetes, although death due to renal disease occurs earlier than that due to coronary heart disease, both causes of death are significantly related to hypertension. Those patients with an onset of diabetes 13 yr of age or younger can expect to live longer following the diagnosis of diabetes mellitus than those with an onset after 13 yr of age, perhaps because hypertension appears at about the same age in both groups. Case/control analysis of the data shows that survivors have significantly less hypertension than those dying of renal or cardiac disease. Furthermore, the close temporal relationship between the onset of hypertension and the onset of proteinuria in patients with either renal or coronary deaths suggests that the hypertension in these patients is renal in origin.

Two other risk factors, smoking and serum lipids, were evaluated in this population. From the data thus far accumulated, neither smoking nor lipids appear to influence mortality significantly. We conclude that hypertension is the major additive risk factor for mortality in juvenile-onset insulin-dependent diabetics.