Prevalence of the metabolic syndrome in hemodialysis.

Background: Recently, the concept of the metabolic syndrome (MS) has emerged in an effort to group and study as a whole several cardiovascular risk factors. The definition of the metabolic syndrome requires the presence of 3 or more of the following parameters: high blood pressure (>/= 130/85), waist circumference >102 cm in men and >88 cm in women, HDL<50 mg/dL in men and <40 mg/dL in women, serum triglycerides >150 mg/dL and fasting blood glucose >/= 110 mg/dL.

Objectives: To investigate the prevalence of the MS and the specific patient characteristics in a cohort of hemodialysis patients.

Materials And Methods: 102 stable patients on maintenance hemodialysis (63 male/39 female with a mean time on dialysis of 57.19 +/- 47.16 months) were studied for 12 months.

Results: The prevalence of the MS is high (56.25%) during the first year on dialysis and gradually declines (44.8% from 2-5 years and 29.7% for >5 years). In total 41/102 patients had MS (40.19%); 28/41 were men (68.29%) and 13/41 women (31.7%). The prevalence of MS in males was 44.4% (28/63) and 33.3% (13/39) in females, while the most frequent combination of risk factors in MS patients was high blood pressure-high waist circumference-high levels of serum triglycerides (36.58%). Serum triglycerides >150 mg/dL is the most frequent component of the MS both in well-nourished patients and according to the duration of dialysis (58.53% for 0-5 years and 19.51% for >5 years on dialysis). MS patients had a better nutritional status and were on dialysis for less time than their non-MS (NMS) counterparts. Actual or anamnestic cardiovascular events and infections did not differ between the 2 groups.

Conclusions: Our study provides new data concerning the prevalence of the MS and the specific patient characteristics in a hemodialysis population. The prevalence of MS in hemodialysis patients is high (40.19%) and seems to reflect a state of good nutrition compared to patients without the MS. Furthermore, the MS is more common in the first years of dialysis (42.46+/-34.29 months) than later on (67.25+/-52.15 months) probably reflecting the long term consequences of the hemodialysis treatment. Our results also indicate that although patients in the MS group were well-nourished and for a shorter time on dialysis, they were not protected from cardiovascular disease and infections. Our study provides new data concerning both the prevalence of the MS and a variety of patient characteristics in a hemodialysis population. Further research and a larger number of patients are required in order to clarify the precise role of this syndrome in patients on MHD.