Roux-en-Y gastric bypass compared with aggressive diet and exercise therapy for morbidly obese patients awaiting renal transplant: a decision analysis.

BACKGROUND

The optimal management of morbidly obese patients awaiting renal transplant is controversial and unknown. The objective of this study was to compare the impact of Roux-en-Y gastric bypass (RYGB) versus diet and exercise on the survival of morbidly obese patients with end-stage renal disease awaiting renal transplant.

METHODS

A decision analytic Markov state transition model was designed to simulate the life of morbidly obese patients with end-stage renal disease awaiting transplant. Life expectancy after RYGB and after 1 and 2 years of diet and exercise was estimated and compared in the framework of 2 clinical scenarios in which patients above a body mass index (BMI) of 35 kg/m(2) or above a BMI of 40 kg/m(2) were ineligible for transplantation, reflecting the BMI restrictions of many transplant centers. In addition to base case analysis (45 kg/m(2) BMI preintervention), sensitivity analysis of initial BMI was completed. Markov model parameters were extracted from the literature.

RESULTS

RYGB improved survival compared with diet and exercise. Patients who underwent RYGB received transplants sooner and in higher frequency. Using 40 kg/m(2) as the upper limit for transplant eligibility, base case patients who underwent RYGB gained 5.4 years of life, whereas patients who underwent 1 and 2 years of diet and exercise gained 1.5 and 2.8 years of life, respectively. Using 35 kg/m(2) as the upper limit, RYGB base case patients gained 5.3 years of life, whereas patients who underwent 1 and 2 years of diet and exercise gained .7 and 1.5 years of life, respectively.

CONCLUSIONS

In morbidly obese patients with end-stage renal disease, RYGB may be more effective than optimistic weight loss outcomes after diet and exercise, thereby improving access to renal transplantation.