Effect of Fasting the Whole Month of Ramadan on Renal Function Among Muslim Patients With Kidney Transplant: A Meta-Analysis

OBJECTIVES: Muslim renal transplant patients often ask whether fasting during Ramadan would be harmful to their kidneys. We performed a meta-analysis on relevant studies to answer this question. MATERIALS AND METHODS: We searched 4 databases using comprehensive search terms with predefined eligibility criteria. Two reviewers (FH and RA) independently assessed the relevance of studies obtained during the search. If disagreement occurred, a consensus would be sought; if disagreement persisted, the arbitration would be left to a third author (AAS). RESULTS: Eight studies (549 patients) were identified as eligible; these studies measured renal function before and after Ramadan with patients acting as their own controls in 5 studies. Our pooled analyses showed no significant changes after fasting with regard to estimated glomerular filtration rate (70.1 ± 9.1 vs 68.5 ± 7.5 mL/min, respectively; P = .6) or in serum creatinine levels (105.3 ± 8.8 and 106.1 ± 6.0 μmol/L, respectively; P = .47). In 4 self-controlled studies (148 patients) that had analyzed changes in systolic and diastolic blood pressure before versus after fasting, no significant differences were shown. However, in 3 studies that assessed changes in glomerular filtration rate in fasting (n = 358) versus nonfasting patients (n = 355), there was a significant difference in change in glomerular filtration rate following Ramadan fasting (-0.13 ± 1.2 mL/min in those who fasted versus 4.2 ± 4.6 mL/min in those who did not fast; P = .039); however, these results were associated with significant publication bias (systematic heterogeneity). CONCLUSIONS: Fasting during Ramadan did not result in significant changes in kidney function or blood pressure in posttransplant patients with good baseline kidney function when patients acted as their own controls.