Age, gender, and body mass index are associated with renal function after kidney donation.

Renal function is thoroughly evaluated before live kidney donation. However, some donors experience impaired recovery of renal function after donation. Our aim was to assess estimated glomerular filtration rate (eGFR) and mean relative (%) increase in creatinine one yr after donor nephrectomy. The study was based on retrospective data from kidney donors during the period 1997-2009. Pre-operative and one-yr follow-up data were available for 721 of 1067 donors. Mean relative increase in creatinine and eGFR were stratified by gender, body mass index (BMI), and age at donation. At one yr post-donation, overweight (BMI > 5 kg/m(2) ) women 50 yr or older experienced the lowest eGFR of 49.6 ± 8.8 mL/min/1.73 m(2) . Men younger than 50 yr with normal weight (BMI < 25 kg/m(2) ) had the highest eGFR of 66.6 ± 10.4 mL/min/1.73 m(2) . Overweight men 50 yr or older had the highest relative increase in creatinine of 49.4% compared to pre-donation. Men under 50 yr with normal weight had the smallest increase in creatinine of 35.2%. In multivariate analysis, older age (p < 0.001), male gender (p < 0.001), and overweight (p = 0.01) were associated with relative increase in creatinine after donation. Potential donors should be offered counseling regarding overweight, as this is a modifiable risk factor.