Obesity and Transplantation Outcomes in Patients with ADPKD

Austin—The rates of renal transplantation among patients with autosomal dominant polycystic kidney disease (ADPKD) are high. Due to the higher incidence of complications post-transplant among patients who are overweight, some patients are required to lose weight prior to being listed for transplant. For patients with local symptoms from organ enlargement, nephrectomy may be performed with transplantation. Data from recent studies suggest there may be an association between obesity and disease progression in patients with ADPKD. It is not known whether enlarged organs from ADPKD contribute to a diagnosis of obesity or overweight.

Jonathan Freise, MD, and colleagues recently conducted a retrospective chart review designed to examine the prevalence of obesity and overweight and the distribution of kidney weights in patients with ADPKD who underwent kidney transplantation and had unilateral or bilateral nephrectomies at a center in California. The researchers reported results during a poster session at the NKF 2018 Spring Clinical Meetings in a poster titled Nephrectomy and Transplantation Analysis in Obese and Overweight Patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD).

Seventy eligible patients between 1998 and 2015 were identified; the researchers recorded the weights of the nephrectomized kidneys along with the patients’ body mass index (BMI) at the time of transplant listing and following transplantation.

The cohort was divided into six BMI categories: <18.5, 18.5 to 24.9, 25 to 29.9, 30 to 34, 34 to 38, and >38. The researchers evaluated the changes in BMI prior to and following transplant. There were no significant differences among the weights of nephrectomized kidneys across BMI categories.

At the time of transplant listing, 24.3% of the cohort was obese, defined as BMI >30. The average weight of a single nephrectomized kidney was 2.2 kg. There were no differences in adverse outcomes by BMI category.

In summary, the researchers said, “Our results might suggest that the BMI transplant listing cutoff could be increased for obese patients with ADPKD to account for weight contributed by enlarged kidneys; however, our data are limited to a single center with ADPKD expertise and may not be generalizable. Healthy weight loss is still encouraged in this group.”

Source: Freise J, Park M, Medhi T, Lee B. Nephrectomy and transplantation analysis in obese and overweight patients with autosomal dominant polycystic kidney disease (ADPKD). Abstract of a poster presented at the National Kidney Foundation 2018 Spring Clinical Meetings, April 10-14, 2018, Austin, Texas.