Risks for donors associated with living kidney donation: meta-analysis

Background: Living kidney donation risk is likely to differ according to donor's demographics. We aimed to analyse the effects of age, sex, body mass index (BMI) and ethnicity. Methods: A systematic review and meta-analysis was undertaken of the effects of preoperative patient characteristics on donor kidney function outcomes, surgical complications, and hypertension. Results: 5129 studies were identified, of which 31 met the inclusion criteria, mainly from the USA and Europe. The estimated glomerular filtration rate (eGFR) in donors aged over 60 years was a mean of 9.54 ml per min per 1.73 m2 lower than that of younger donors (P < 0.001). Female donors had higher relative short- and long-term survival. BMI of over 30 kg/m2 was found to significantly lower the donor's eGFR 1 year after donation: the eGFR of obese donors was lower than that of non-obese patients by a mean of -2.70 (95 per cent c.i. -3.24 to -2.15) ml per min per 1.73 m2 (P < 0.001). Obesity was also associated with higher blood pressure both before and 1 year after donation, and a higher level of proteinuria, but had no impact on operative complications. In the long term, African donors were more likely to develop end-stage renal disease than Caucasians. Conclusion: Obesity and male sex were associated with inferior outcomes. Older donors (aged over 60 years) have a larger eGFR decline than younger donors, and African donors have a higher incidence of ESRD than Caucasians.