Association of hypertriglyceridemia and insulin resistance in uremic patients undergoing CAPD

. Objective: Hyperlipidemia is frequently encountered in uremic patients an d may be worsened by continuous ambulatory peritoneal dialysis (CAPD) treat ment. The lipid abnormalities in these patients may be multifactorial. Insu lin resistance (or its compensatory hyperinsulinemia) is commonly observed in uremic patients, but its association;with hyperlipidemia in these patien ts has not been studied. . Patients and Methods: Lipid profiles of 35 nondiabetic nonobese patients undergoing CAPD for more than 1 year (mean 52.3 months) were studied. Curre nt laboratory data and parameters related to peritoneal dialysis (PD) withi n the previous 3 months were recorded. After overnight fasting and interrup tion of PD, an oral 75-g glucose tolerance test (OGTT) was examined. . Results: After CAPD treatment for more than 12 months, these patients had higher serum triglyceride (TG) (p = 0.001) and total cholesterol (p = 0.00 58) levels than their values before commencing CAPD. Twelve of 14 patients with serum TG higher than 200 mg/dL (high-TG) were diagnosed de novo, in co ntrast with only 1 patient diagnosed of de novo hypercholesterolemia (total cholesterol > 240 mg/dL). There was no difference in age, gender, body mas s index (BMI), duration of Po treatment, serum albumin, hematocrit, intact serum parathyroid hormone (iPTH), peritoneal glucose load, solute transport , or weekly Kt/V urea between normal-TG and high-TG patients. After adjusti ng for age, gender, BMI, weekly Kt/V urea, and iPTH, the high-TG patients h ad higher levels of area under the curve for glucose (AUC(Glu)), area under the curve for insulin (AUC(lns)), and AUC(lns)/AUC(Glu) ratios (F = 10.63, 10.14, and 8.65; p= 0.0029, 0.0035, and 0.0065, respectively), indicating that the high-TG patients were more insulin resistant. There were 24 patien ts with normal glucose tolerance (NGT), and 11 patients with impaired gluco se tolerance (IGT). The IGT group had higher serum TG (F = 10.43, p = 0.003 ) and total cholesterol (F = 8.05, p = 0.009) than the NGT group, after adj usting for BMI, duration of CAPD treatment, peritoneal glucose load, solute transport, serum albumin, and lipid levels before PD treatment. The TG lev els after CAPD treatment were positively correlated with AUC(Glu), AUC(lns) , and AUC(lns)/AUC(Glu) ratio (r = 0.48, 0.53, and 0.49; p = 0.0037, 0.001, and 0.0028, respectively). . Conclusions: These results indicate that insulin resistance is an importa nt factor in the development of hypertriglyceridemia in CAPD patients.