Cardiovascular risk assessment and homocysteine and leptin levels in peritoneal dialysis and hemodialysis patients.

In the present study, we used high sensitivity C-reactive protein (hs-CRP) analysis in combination with lipid screening [which has been reported to be a more valuable risk marker than other novel markers such as homocysteine (Hcy) and lipoprotein a] to perform cardiovascular risk assessment in peritoneal dialysis (PD) and hemodialysis (HD) patients. We selected 9 PD patients, 10 HD patients, and 9 control subjects for the study. In those patients, we determined levels of serum lipids, hs-CRP, Hcy, vitamin B12, folic acid, and leptin. Patients on PD had a significantly elevated hs-CRP concentration (3.14 +/- 0.79 mg/L) and ratio of total cholesterol (TC) to high density lipoprotein (HDL) cholesterol (4.71 +/- 0.40), and their cardiovascular risk was found to be three times that of control subjects. In HD patients, the elevation of hs-CRP was more profound (5.66 +/- 1.30), but their TC:HDL ratio fell within the normal range (3.18 +/- 0.13). However, a cardiovascular risk assessment of the HD group showed the same risk as in the PD group. Serum Hcy was also elevated in patients on PD (54.95 +/- 18.08 microl/L) and on HD (25.33 +/- 3.70 micromol/L) as compared with healthy subjects (13.76 +/- 0.94 micromol/L). Folic acid and vitamin B12 levels (needed to remethylate Hcy to methionine) were not compromised in the dialysis population. On the other hand, leptin secreted by adipose tissue was found to be mildly higher in PD patients (37.08 +/- 12.59 ng/mL). The mean leptin level in control subjects was 14.14 +/- 3.60 ng/mL. The proinflammatory and proangiogenic action of excess leptin may aggravate cardiovascular risk in PD patients. Increased values of known risk factors were found in dialysis patients on PD and on HD. However, lower levels of HDL cholesterol, higher cardiovascular risk assessment and Hcy levels, and mildly increased leptin levels seem to increase the potential threat of vascular disease in PD patients more than in HD patients.