Among living kidney donors, the long-term risk of ESRD is close to doubled for those who are obese, reports a study in Kidney International.
The study included data on 119,769 living kidney donors, linked to Centers for Medicare & Medicaid Services data to determine ESRD status. There were 20,588 obese donors, body mass index (BMI) 30 kg/m2 or higher; and 58,004 nonobese donors. (The remaining 41,177 donors had missing data on BMI.) Postdonation risk of ESRD was compared between groups, with adjustment for potential confounders.
Twenty years after living kidney donation, the cumulative incidence of ESRD was 93.9 per 10,000 for obese donors versus 39.7 per 10,000 for nonobese donors. In adjusted models, obesity was the only potentially modifiable risk factor associated with increased ESRD risk: adjusted hazard ratio 1.86. For each one-unit increase in BMI over 27 kg/m2, there was a 7% increase in ESRD risk.
While the absolute risk of ESRD after living kidney donation is low, the risk is significantly higher for obese donors. The increase in risk begins at a donor BMI of 27 kg/m2—below the standard cutoff for obesity. The authors discuss the implications for living donor selection practices, including the possibility of predonation rehabilitation or weight loss programs [Locke JE, et al. Obesity increases the risk of end-stage renal disease among living kidney donors. Kidney Int 2016; DOI: http://dx.doi.org/10.1016/j.kint.2016.10.014].