Proteinuria and cardiovascular disease.

In the last few decades, clinical and experimental data have established microalbuminuria/proteinuria as an independent risk factor for renal disease and for progression of renal disease in patients with diabetes and in those with essential hypertension. Reduction of proteinuria with the use of angiotensin-converting enzyme inhibitors has been shown in clinical trials to delay or stabilize the rate of progression of renal disease. This effect appears to be independent of any effect on blood pressure control. In conjunction with other therapeutic interventions such as dietary modification and control of serum lipids, it appears that for at least a subgroup of patients, it is possible to delay or prevent progression of kidney failure. More recently, evidence has accumulated that establishes microalbuminuria/proteinuria as an independent risk factor for cardiovascular morbidity and mortality even in those without other clinical evidence of kidney disease. There is frequently a clustering of risk factors in these individuals that includes insulin resistance, salt-sensitivity, hypertension, and dyslipidemia. The mechanism of this relationship of proteinuria and cardiovascular disease is unclear, but the presence of proteinuria as a marker for cardiovascular disease has important implications for the identification and treatment of individuals at risk.