Effect of clinical condition and mycophenolate mofetil on plasma retinol, α-tocopherol and β-carotene in renal transplant recipients

Introduction: Plasma antioxidant vitamins (retinol, α-tocopherol, β-carotene) were measured to establish the influence of clinical condition and mycophenolate mofetil (MMF) treatment on the nutritional status of renal transplant recipients.

Material and methods: In 106 adult patients plasma vitamins were measured and 24-h diet history questionnaires were conducted. The MMF influence on plasma vitamins was verified in 61 patients.

Results: The current dietary intakes of vitamins in daily food rations were lower than recommended. Plasma retinol was lower in patients suffering from gastrointestinal disorders (1.25 ±0.48 mg/l vs. 1.55 ±0.70 mg/l) and inversely associated with aminotransferases activity (p = 0.019) and creatinine clearance (p = 0.021). Retinol concentrations were positively associated with plasma creatinine (p = 0.027) and pharmacokinetic parameters of MMF phenyl glucuronide. β-Carotene concentrations were higher in women (0.39 ±0.46 mg/l vs. 0.28 ±0.23 mg/l; p = 0.041) and when MMF was co-administered with cyclosporine vs. tacrolimus (0.45 ±0.62 mg/l vs. 0.25 ±0.19 mg/l). Plasma α-tocopherol correlated negatively with the mycophenolic acid pre-dose concentration (p = 0.027) and was significantly lower in patients treated with calcineurin inhibitors (8.90 ±5.23 mg/l vs. 12.25 ±5.62 mg/l). A positive correlation was observed between α-tocopherol levels and aspartate aminotransferase (p = 0.006). In multivariate regression aspartate aminotransferase and MMF treatment significantly influenced retinol (p < 0.001).

Conclusions: The MMF treatment was associated with significantly lower retinol concentrations. The gastrointestinal disorders occurrence in MMF-treated patients may cause a decrease in retinol absorption. Diet adjustment and/or vitamin A supplementation should be considered.