The Impact of Obesity and Associated Comorbidities on the Outcomes after Renal Transplantation with a Living Donor vs. Deceased Donor Grafts

Abstract

Background: Obesity among kidney transplant (KT) recipients can lead to metabolic comorbidity-associated deaths. This study compares post-KT survival between obese and non-obese patients and outcomes of living donor (LD) and deceased donor (DD) grafts. Methods: Between January 2005–May 2019, 1403 KT recipients from a single center were included in the study, as well as 314 patients (22.4%) with obesity (BMI > 30 kg/m2), 137 DD transplants, and 177 LD transplants. Of the 1089 (77.6%) in the control group (BMI ≤ 30 kg/m2), 384 were DD transplants and 705 LD transplants. The Kaplan–Meier method was used for survival analysis and a Cox regression was used to identify risk factors for graft loss and mortality. Propensity score matching analysis adjusting for age, IHD, and T2DM was performed. Results: The study group had higher incidence of obesity related comorbidities, delayed graft function and primary non function (p < 0.001). One-, 5-and 10-year patient and graft survival were lower in the study group (p < 0.001). Subgroup analysis of graft survival according to type of graft shows a difference in the DD (p = 0.002) but not in the LD group (p = 0.220). However, mortality was higher in both groups (LD, p = 0.045; DD, p = 0.004). Risk factors for mortality were age, T2DM, IHD, and DD, and for graft failure: IHD, BMI, donor age, re-transplant, and DD. Propensity score analysis shows an odds ratio of 0.81 for graft failure and 0.93 for death in the study group (95% CI = 0.55, 1.21, p = 0.3 and CI = 0.59, 1.46, p = 0.7, respectively). Conclusions: Recipient age and metabolic comorbidities should be emphasized when evaluating patients with obesity. We suggest considering weight loss interventions using the new GLP-1 inhibitors and bariatric procedures in selected patients to prepare overweight patients for transplant.

Abdominal Organ Transplantation: Noteworthy Literature in 2022

“…Obesity among KTx recipients and its association with graft outcomes was another area of study. Obesity was associated with decreased graft survival, more DGF, increased postoperative surgical complications, [24][25][26] longer procedure duration, and longer warm ischemia time. 27 Tsapepas et al found that body mass index (BMI) ≥35 was associated with increased surgical site infections on multivariable analysis (adjusted OR 3.34; 95% CI 1.55-7.22; P = .022), though this study did not find the increased rate of graft failure in obese patients that was found in prior studies.…”

Obesity and kidney transplantation

“…Obesity is associated with increased risk for delayed graft function (DGF), defined as the need for dialysis within 7 days after transplantation but the underlying cause for this remains unclear [13,14 ▪ ,15–18,19 ▪ ,25–29]. Although obesity is associated with a proinflammatory environment with elevated levels of cytokines and chemokines, technical challenges encountered in performing the transplantation may lead to a longer warm ischemic time and other anatomical challenges.…”

“…It is conceivable that this is because of improvement in general posttransplant care including advances in immunosuppressive therapy. A recent single-center study reported that recipients with a BMI greater than 30 kg/m 2 had higher risk of both graft and patient loss at 1, 5, and 10 years after transplantation compared wth control group (BMI ≤30 kg/m 2 ) [28]. This is in contrast to the retrospective study by Jarv that reported that obesity (BMI ≥25 kg/m 2 ) was associated with worse short-term (5-year) graft (BMI <25 versus ≥25 kg/m 2 , 67 versus 61%, P < 0.05) and patient survival (BMI <25 versus ≥25 kg/m 2 , 80 versus 70%, P < 0.05), but no statistically significant difference in long-term (10-year) graft survival, and only minimal difference in long-term patient survival [36].…”

“…The higher prevalence of comorbidities such as cardiovascular disease, dyslipidemia, diabetes, and hypertension in obese individuals may negatively affect long-term allograft survival. Although some studies reported a negative impact of obesity on graft and patient survival [13,17,[26][27][28], others found no association [15,20,34,35]. A meta-analysis that compared outcomes of obese and nonobese patients who underwent kidney transplantation suggested that obesity was associated with increased risks for graft loss and death only in the analysis of studies that evaluated patients who received a transplant before year 2000 [25].…”

Weight loss with GLP-1 analogues in preparation for transplantation

“…The prevalence has nearly tripled over the last 50 years due to less healthy diets and progressively more sedentary lifestyles 1. At present, more than one-third of the world’s population meet the criteria for obesity 2. It is associated with increased morbidity and mortality, exacerbating underlying conditions such as heart disease, renal disease and liver disease, which, in turn, can lead to end-stage organ disease 3.…”