To obtain information about predialysis characteristics and long-term outcome of patients on peritoneal dialysis (PD) for more than 4 years, we reviewed all patients starting PD who performed continuous ambulatory peritoneal dialysis (CAPD) and were at risk for more than 4 years. Sixty-two patients started; 42% were diabetic and 35% over age 60. Three recovered renal function, seven received transplants, and 12 switched to hemodialysis. Nineteen survived more than 4 years (long-term survivors, LTS), eight diabetic and 12 male. Twenty-one died on CAPD in less than 4 years (short-term survivors, STS). In comparison to STS, LTS were younger, with less prior cardiac disease, yet had higher predialysis serum creatinine values and lower hematocrits. LTS were observed for a mean of 65.3 +/- 3 months (48 to 91 months), and STS for a mean of 21 +/- 2 months. When compared to STS, LTS had fewer hospital days, hospital days for peritonitis, and a lower peritonitis rate, although the incidence of Staphylococcus aureus peritonitis was greater in LTS. Cardiovascular and thromboembolic events were less frequent in LTS, but bone fractures were seen more often in the LTS diabetic patients. Weight gain, especially in males, and hernias were noted in both groups. BP improved, and vision was maintained in both groups. Non-PD-related infections causing hospitalization were low in both groups. Improved mean hematocrit and hemoglobin A, values were seen only in LTS. Mean serum cholesterol values increased with time in LTS. This study reveals that potentially high-risk patients such as diabetics and the elderly can have prolonged survival on PD.(ABSTRACT TRUNCATED AT 250 WORDS)