Incidence of diabetes mellitus requiring insulin treatment after renal transplantation in patients with hepatitis C

Background. Hepatitis C virus (HCV) infection has been associated with an increased incidence of diabetes mellitus, both in the general population and among transplant patients. Methods. To test this hypothesis, we reviewed the records of 1614 patients who had undergone renal transplant at six Spanish centres between 19921 and 1998. We established the rate of onset of diabetes mellitus requiring >1 month of treatment with insulin (insulin-treated diabetes mellitus, I-TDM) among the 177 patients showing HCV antibody seropositivity at the time of transplant (HCV+ group). As controls, 177 HCV patients were selected who had received a kidney allograft immediately before or after the Study patients at the same centre. Results. The HCV+ patients were well matched with controls in terms of characteristics (except a longer time on dialysis) and immunosuppressive treatment. After a mean follow-up of 44 months, 28 cases of I-TDM were diagnosed (9.6% in HCV+ and 6.2% HCV-, not significant (NS); odds ratio 1.6; 95% confidence interval 0.75-3.50). The onset of I-TDM was somewhat later in HCV+ patients (467 days vs 292 days in HCV-patients, NS). Multivariate analysis identified the following prognostic factors for I-TDM onset: age and BMI at the time of transplant, and polycystic kidney disease as the underlying cause of chronic renal insufficiency. No correlation was found with HCV positivity or time on dialysis. Conclusions. We were unable to confirm a greater incidence of post-renal transplant insulin-requiring diabetes in association with HCV infection. However, the observed tendency towards such an association suggests that the follow-up period would need to be extended.