Kidney Transplantation Significantly Improves Patient and Graft Survival Irrespective of BMI: A Cohort Study : High BMI and Kidney Transplantation

The aim of this study was to investigate the predictive value for all-cause and cardiovascular (CV) death of anthropometric measurements of abdominal obesity in patients with end-stage renal disease (ESRD). Surrogate measures of abdominal obesity and segmental fat distribution (waist circumference and waist/hip ratio [WHR]) are stronger predictors of all-cause and CV death than body mass index (BMI) in the general population, but the issue has never been investigated in patients with ESRD. We performed a prospective cohort study in 537 patients with ESRD (age 63 +/- 15 years). In BMI-adjusted Cox models, waist circumference was a direct predictor of all-cause and CV mortality (p < 0.001), whereas BMI showed an inverse relationship (p < 0.001) with these outcomes. The incidence rates of overall and CV death were maximal in patients with relatively lower BMI scores (below the median) and higher waist circumferences (at least the median) and minimal in patients with higher BMI scores (at least the median) and small waist circumferences (below the median). The prognostic power of waist circumference for all-cause (hazard ratio [HR] [10-cm increase]: 1.23; 95% confidence interval [CI]: 1.02 to 1.47; p = 0.03) and CV mortality (HR: 1.37; 95% CI: 1.09 to 1.73; p = 0.006) remained significant after adjustment for CV comorbidities and traditional and emerging risk factors. WHR was found to be related to all-cause (p = 0.009) and CV mortality (p = 0.07). Abdominal obesity underlies a high risk of all-cause and CV mortality in patients with ESRD. Redefinition of nutritional status by combining the metrics of abdominal obesity and BMI may refine prognosis in the ESRD population.

Changes in organ allocation policy in 2002 reduced the number of adult patients on the liver transplant waiting list, changed the characteristics of transplant recipients and increased the number of patients receiving simultaneous liver-kidney transplantation (SLK). The number of liver transplants peaked in 2006 and declined marginally in 2007 and 2008. During this period, there was an increase in donor age, the Donor Risk Index, the number of candidates receiving MELD exception scores and the number of recipients with hepatocellular carcinoma. In contrast, there was a decrease in retransplantation rates, and the number of patients receiving grafts from either a living donor or from donation after cardiac death. The proportion of patients with severe obesity, diabetes and renal insufficiency increased during this period. Despite increases in donor and recipient risk factors, there was a trend towards better 1-year graft and patient survival between 1998 and 2007. Of major concern, however, were considerable regional variations in waiting time and posttransplant survival. The current status of liver transplantation in the United States between 1999 and 2008 was analyzed using SRTR data. In addition to a general summary, we have included a more detailed analysis of liver transplantation for hepatitis C, retransplantation and SLK transplantation.

Current billing practices and mandates to report surgical outcomes are disincentives to surgical treatment of obese patients, who are at increased risk for longer hospital stays and higher complication rates. The objective of this study was to quantify the independent association between body mass index (BMI) and waiting time for kidney transplantation to identify potential provider bias against surgical treatment of the obese. A secondary data analysis was performed of a prospective cohort of 132,353 patients who were registered for kidney transplantation in the United States between 1995 and 2006. Among all patients awaiting kidney transplantation, the likelihood of receiving a transplant decreased with increasing degree of obesity, categorized by ranges of BMI (adjusted hazard ratios 0.96 for overweight, 0.93 for obese, 0.72 for severely obese, and 0.56 for morbidly obese, compared with a reference group of patients with normal BMI). Similarly, the likelihood of being bypassed when an organ became available increased in a graded manner with category of obesity (adjusted incidence rate ratio 1.02 for overweight, 1.05 for obese, 1.11 for severely obese, and 1.22 for morbidly obese). Although matching an available organ with an appropriate recipient requires clinical judgment, which could not be fully captured in this study, the observed differences are dramatic and warrant further studies to understand this effect better and to design a system that is less susceptible to unintended bias.