Peritoneal dialysis in the geriatric patient. Elderly patients on chronic peritoneal dialysis (CPD) from two large chronic peritoneal dialysis programs were compared with younger patients in regard to peritonitis rates, catheter problems, hospital days, transfers to other forms of therapy, and mortality. Peritonitis rates and organisms were similar in younger and older patients. Catheter replacements were less common in the elderly. Differences in hospital days were attributable to hospitalization for vascular disease. The elderly were more likely to have the first episode of peritonitis, to die and to change dialysis modalities at all times after the first year of continuous ambulatory peritoneal dialysis (CAPD) treatment, although other than increased mortality, differences between the two groups were small. CPD appears to be an acceptable form of renal replacement therapy in the elderly. 