Comparative study of two different routes for insulin administration in CAPD diabetic patients. A multicenter study

CAPD has been considered an appropriate method for treatment of diabetics in renal failure. Up to now the choice of route for insulin administration in these patients has not been definitely defined, although there is a general consensus for employing the intraperitoneal route for this purpose. However, contradictory data have appeared on this subject. Our aim has been to investigate whether the subcutaneous or intraperitoneal route makes any difference to metabolic control, and if so what is the price in terms of the incidence of peritonitis. Two groups of diabetic patients from three different hospitals with a similar peritonitis incidence and training protocols were studied. Of the 30 patients, 15 were treated with subcutaneous insulin (sc group) and in the other 15 the intraperitoneal route was employed (ip. group). The average follow-up period was 20.8 +/- 7.5 months for sc group and 18.7 +/- 8 months for ip. group. Insulin requirements were 30 +/- 11 u./day in the sc. and 110 +/- 60 u/day in the i.p. group (p less than 0.05) and remained constant during the study period. Metabolic controls (home glucose levels, HbA1C, hospital fasting glucose levels) were similar for both groups. However, the incidence of peritonitis was 4 times greater in the ip. group. In the ip. group 18 peritonitis episodes were registered in 280 patient-months vs 5 episodes in sc. group in 312 patient-months. We conclude that the intraperitoneal route for insulin administration in diabetic CAPD patients produces a higher risk of suffering peritonitis with no real metabolic improvement in the medium term.