Background: Homocysteine and advanced glycation end-products (AGEs), which accumulate in chronic kidney disease (CKD), are recently proposed cardiovascular risk factors. In this study, we evaluated the association between changes in calculated intima media (cIM) area of the common carotid artery during the first year of dialysis therapy and plasma total homocysteine (tHcy) level as well as circulating AGEs such as plasma pentosidine level.
Methods: We studied 63 CKD patients (38 males) aged 52 +/- 12 years at a time-point close to start of dialysis treatment and after 12 months of dialysis treatment (41 on peritoneal and 22 on hemodialysis). The tHcy and plasma pentosidine levels were measured by HPLC. Change in cIM area was evaluated by non-invasive B mode ultrasonography. Malnutrition was assessed by subjective global assessment (SGA).
Results: At basal, 70% of the patients had carotid plaques, 32% had symptomatic CVD, 38% had malnutrition, 30% had inflammation (CRP > or = 1 mg/dl) and 23% had diabetes mellitus, respectively. At baseline, the mean plasma pentosidine levels were similar in the patients with and without carotid plaques (36 +/- 21 vs 36 +/- 19 pmol/mg albumin, respectively), whereas the median plasma tHcy was significantly lower in the patients with carotid plaques than in the patients without carotid plaques (32 +/- 21 vs 52 +/- 42 pmol/l, p < 0.01, respectively). The prevalence of hyperhomocysteinemia (tHcy level > 13.7 micromol/l) was 95%. In univariate analysis, the change in cIM area during the first year of dialysis was significantly correlated with basal plasma pentosidine level (p = 0.31, p = 0.01), but not with basal tHcy (p = -0.11). However, neither pentosidine nor tHcy levels were correlated with cIM area at basal or at 12 months. In a stepwise multiple regression model, age and plasma pentosidine content, but not the tHcy level, associated with changes in the cIM area.
Conclusion: Progression of atherosclerosis, as indicated by changes in carotid intima-media area during the course of dialysis treatment, was associated with pentosidine, but not with tHcy, levels at baseline in these CKD patients. This suggests that the accumulation of AGEs in CKD patients may have a role in the pathogenesis of CVD in these patients. Since almost all CKD patients have hyperhomocysteinemia, this finding, however, does not exclude a role ofhomocysteine as a risk factor for CVD in CKD patients.