Renal disease in the elderly: the role of the renal biopsy.

The causes of renal disease in the young and the elderly vary in their frequency. There are many indications for renal biopsy in older patients, with the nephrotic syndrome (NS) being the most common, followed by acute renal failure. Biopsy does not carry a greater risk for older patients, but there is a greater risk of complications when there is coexistent renal insufficiency. Interpretation of the renal biopsy in elderly patients may be more complex because of changes associated with aging or intercurrent disease--arteriolar sclerosis and global sclerosis. A prospective study is needed to determine the exact prevalence of renal insufficiency, NS, and other renal diseases in noninstitutionalized elderly individuals and to determine the role of renal biopsy in making these determinations.