Renal issues in the management of hypertension.

Progressive renal failure is a significant complication of hypertension, a major cause of end-stage renal disease. In hypertensive patients, the markers of impaired renal function are abnormal levels of serum creatinine and microalbuminuria. Serum creatinine measurements, which can be adjusted for age and gender by using a simple formula, are used to estimate creatinine clearance and glomerular filtration rate. Microalbuminuria is an early sign of renal damage found in 20% to 30% of cases of essential hypertension and foretells the development of nephropathy and other complications. Current general guidelines for managing hypertension associated with renal impairment recommend controlling blood pressure, pharmacologically if necessary; adding a diuretic, if initial monotherapy is not effective; and reducing dietary sodium intake. Diuretic drugs remain the cornerstone of antihypertensive therapy for patients with renal failure, whereas beta-blockers, calcium channel blockers, and angiotensin-converting enzyme inhibitors have varying effects and continue to be investigated intensively. In a study undertaken by the National Institute of Diabetes and Digestive and Kidney Diseases, the different classes of antihypertensive drugs are currently being evaluated for their ability to slow progressive renal failure.