Apolipoprotein Clearance and Atherogenicity in CAPD: Protein and lipoprotein loss is one of the disadvantages of CAPD. The impact of these losses on serum constituents is not fully understood. Lipoprotein disorders are observed in patients with chronic or acute renal failure or undergoing dialytic therapy with resultant increase in atherosclerotic clinical events yet these phenomenon are poorly understood, underinvestigated and underreported. Thus the impact of dietary and pharmacological steps to prevent these events are limited by lack of clinical facts. The recent emergence of effective lipid lowering agents makes a rapid analysis of parameters important. We studied the relationships between peritoneal clearance of apolipoproteins and serum atherogenicity indicators in a preliminary study of 10 CAPD patients with and without peritonitis. We measured total cholesterol (TC), HDL-Cholesterol (HDL-C), Apo A-I and Apo B and dialysate levels of Apo A-I and Apo B. Apo levels were determined immunotubidimetrically, and dialysate was concentrated by ultrafiltration. A subsequent prospective group of 10 additional patients was studied to test the relationship found in the preliminary study. In both preliminary and prospective nonperitonitis groups, the ratio of peritoneal clearance of Apo A-I to Apo B correlated strongly with the serum TC/HDL-C (r = 0.9 preliminary, r = 0.78 prospective group). There was an inverse correlation between the clearance ratio and both serum HDL-C (r = -0.71 preliminary, r = -0.77 prospective group) and serum Apo A-I/Apo B (r = -0.74 preliminary, r = -0.62 prospective group).(ABSTRACT TRUNCATED AT 250 WORDS)