The donor, recipient, and societal risks and benefits associated with potential obese live kidney donors (OLKD) undergoing bariatric surgery prior to donation

K Rock, A Cash, I Driskell, A Baskara, J Ortiz. The University of Toledo Medical Center

Introduction: Data shows that the number of living donor transplants has declined from 6241 in 2002 to 5624 in 2012. Elevated donor BMI is a common exclusion criterion for kidney donation (KD). Obese individuals who undergo bariatric surgery (BS) could contribute to the donor pool.

Methods: A review of PubMed literature was conducted to determine the potential health risks and benefits of obese donors undergoing BS prior to KD.

Results: Over 5,000 end stage renal disease (ESRD) patients die each year awaiting transplant. An ESRD patient undergoing dialysis has a 50% reduction in life expectancy. After three years of allograft function, transplantation is cost effective. ESRD accounts for 6.3% of the total Medicare budget (US$34.3 billion/yr), and average cost of hemodialysis is $87,945/yr/individual while transplantation costs $32,922/yr. In transplant recipients, quality of life (QOL) is better than ESRD patients (79.1% vs. 50%). The graft survival rate for LKD is better compared to deceased donor  (93% vs. 80%) and also has longer duration of function (12 to 20 years vs. 8 to 10). 10 year average graft survival with obese kidney is 70% and is associated with higher percentages of delayed graft function (22.9%) and primary non-function (2.8%). Donation post weight loss surgery has a 10-year graft survival comparable to a normal weight LKD.

            Live donors have a 28 in 10,000 estimated lifetime risk of developing ESRD by age 50. Surgical mortality for KD is 0.1-0.3%. OLKDs have higher conversion rates with 16% complication rate compared to 5%. High BMI donors had longer operative times (mean increase 19 min). 47.2% of OLKDs have a post donation MDRD-eGFR <60 mL/min. Hypertension is more common among OLKDs (17.2% vs. 8.2%), and they are at higher risk of developing diabetes mellitus. The donor remains obese, with healthcare per capita spending $1,429 (41.5%) greater than normal weight individuals.

            Average cost of sleeve gastrectomy is $16,800 with achieved average excess weight loss of 60-80% over 3-5 years. Reduction for death rates among those who had weight loss surgery was 56% for death from coronary artery disease, 92% from diabetes and 60% from cancer. thisshould be removed since we would never use a donor with a history of diabetes  In the paper, you can emphasize the AVOIDANCE of diabetes but you can’t discuss the improvement of diabetes because we would never use these donors and experience positive effects on angina and QOL. 30-day mortality rate for sleeve gastrectomy is 0.08%, gastric bypass 0.14%, and gastric banding 0.03%. Long-term complications include anastomotic leaks, formation of hernias, nutritional deficits, and emotional disorders.

Conclusion: Benefits of live kidney donation to both the recipient and society are obvious. Donation from obese live donors is associated with worse donor and recipient outcomes. Health benefits to obese donors who undergo bariatric surgery prior to donation are not as clear. Proposed benefits supported by our analysis are increased longevity of life, lower surgical risks during nephrectomy, better renal outcomes, and other long-term health benefits of weight loss.