LOWER SERUM MAGNESIUM 1-YEAR POSTTRANPLANTATION IS ASSOCIATED WITH PROLONGED USE OF PROTON PUMP INHIBITORS AND DECREASED GRAFT SURVIVAL IN RENAL TRANSPLANT RECIPIENTS

Abstract

Introduction and Aims: Hypomagnesaemia is a known side effect of immunosuppressive regimen, especially calcineurin inhibitors, and has been associated with new onset diabetes after transplantation (NODAT), decreased graft survival in chronic cyclosporine nephrotoxicity and vascular stiffness. Proton pump inhibitors-induced hypomagnesaemia has been described recently, although its relevance in renal transplant recipients is still unknown. Methods: We conducted a single center cross-sectional retrospective study of renal transplantations performed between 2006 and 2011 in order to evaluate the impact of low serum magnesium (Mg) levels in patient and graft outcomes. Serum Mg levels 1-year after renal transplantation were available for 316 patients. Results: The median follow-up was 1062 days (range, 284–2287). Patients were divided into four groups, based in quartiles of serum Mg levels, and no significant differences were found regarding sex, age, pretransplantation cholesterol, albumin, triglycerides, body mass index, donor age and type, immunosuppressive regimen, use of Mg supplements, delayed graft function, acute rejection, CMV and HCV infection, or NODAT development. Patients with Mg < 1.6 mg/dL (n=80) had a higher frequency of prolonged (> 1 year) proton pump inhibitors use (90% vs. 81%, p=0.04), when compared to patients with Mg > 2 mg/dL (n=81). Using Cox multivariate regression analyses, adjusted for recipient age, donor age and type, immunosuppressive regimen, diabetes, NODAT and presence of acute rejection, graft survival was significantly reduced in the low Mg group after 4.6 years posttransplantion (p=0.001). Conclusions: Hypomagnesaemia 1-year posttransplantation, possibly related to prolonged use (> 1 year) of proton pump inhibitors, is associated with decreased graft survival in renal transplant recipients.