Metabolic syndrome in hemodialysis patients as a risk factor for new-onset diabetes mellitus after renal transplant: a prospective observational study

Josep Bonet¹, Albert Martinez-Castelao², Beatriz Bayés<sup>1

1</sup>Department of Nephrology, Hospital Universitari Germans Trias i Pujol, Badalona, Spain; ²Department of Nephrology, Hospital Universitari de Bellvitge, IDIBELL, Hospitalet de Llobregat, Barcelona, Spain

Purpose: Metabolic syndrome is a cluster of biochemical abnormalities including cardiovascular and diabetes risk factors. The development of diabetes mellitus after renal transplant represents a major posttransplant complication that may adversely affect graft/patient survival. The aim of this study was to assess the role of metabolic syndrome in patients on hemodialysis as a risk factor for the incidence of new-onset diabetes mellitus after renal transplant.
Patients and methods: This was a prospective observational epidemiologic study carried out in adult nondiabetic patients undergoing chronic hemodialysis and on the renal transplant waiting list between November 2008 and April 2009. Patients were followed up from Visit 1 (baseline) to 6 months after the renal transplant. The analysis of the role of metabolic syndrome in hemodialysis patients as a risk factor for the incidence of new-onset diabetes mellitus after renal transplant included the estimation of relative risk and its 95% confidence interval (CI).
Results: A total of 383 evaluable patients were entered into the study (mean age, 52.7 years; male, 57.7%; Caucasian, 90.1%). The prevalence of metabolic syndrome on hemodialysis was 30.4% (95% CI, 25.8%–35.4%). Hypertension was the most prevalent criterion for metabolic syndrome (65.0%), followed by low levels of high-density lipoprotein cholesterol (52.7%), abdominal obesity (36.2%), hypertriglyceridemia (32.4%), and impaired glucose (8.9%). After the renal transplant, the prevalence of metabolic syndrome was still 25.8%. During the posttransplant period, the incidence of new-onset diabetes mellitus reached 13.0% (95% CI, 7.8%–20.6%) and patients with pretransplant metabolic syndrome were 2.6 times (95% CI, 1.043–6.608) more likely to develop new-onset diabetes mellitus after the renal transplant than those without metabolic syndrome.
Conclusion: The presence of metabolic syndrome in patients undergoing hemodialysis represents an independent risk factor for the incidence of new-onset diabetes mellitus after renal transplant.

Keywords: dialysis, kidney transplantation, metabolic syndrome X, posttransplant diabetes