Systemic hypertension, diabetes mellitus and the kidney.

Diabetic nephropathy is manifested by albuminuria, hypertension and progressive loss of renal function. Only one-third of patients with insulin-dependent diabetes mellitus of juvenile onset develop nephropathy and the risk of nephropathy does not increase with increasing duration of diabetes. Hypertension occurs almost exclusively in patients with nephropathy. Therefore, there is a subset of patients at risk for both nephropathy and hypertension. It is important to identify the patients destined to develop nephropathy, to define the pathophysiology responsible for the nephropathy in this subset of patients and to develop programs to interrupt the pathophysiology early in its course and hopefully prevent the progression to end-stage renal failure. Potential markers to identify patients who will develop nephropathy include a family history of hypertension, increased glomerular filtration rate and renal mass and presence of significant microalbuminuria. Studies are needed to evaluate various classes of drugs for their efficacy in altering the pathophysiologic hemodynamic changes leading to nephropathy.