Kidney transplant outcomes in obese pediatric patients

Table 1 The table summarizes the renal transplantation outcomes in obese pediatric patients

	Ref.	Population	Control	Results
Kidney transplant in obese pediatric patients	Stanicki et al[6]. Retrospective study	Recipients (23081) aged < 18 years	None	Class 3 obese recipients had lower 1-year graft survival (88.7%) compared to healthy-weight recipients (93.1%, P = 0.012). Underweight recipients had lower 10-year patient survival (81.3%, P < 0.05) than healthy-weight recipients. Class 2 and 3 obese recipients had the lowest 5-year graft survival (67.8% and 68.3%, P = 0.013) and Class 2 obesity had the lowest 10-year graft survival (40.7%). Cox regression identified increases in BMI category as an independent predictor of graft failure [(HR) = 1.091, P < 0.001] and mortality (HR = 1.079, P = 0.008). Obese patients experienced longer cold ischemia times (11.6 and 13.1 hours vs 10.2 hours, P < 0.001). Class 3 obesity had the highest proportion of Black recipients (26.2% vs 17.9%, P < 0.001)
	Saygılı et al[29]. Cross-sectional, single-center study	Recipients (52) aged from 13.8 to 18.4 years	None	Nineteen patients (36.5%) were obese or overweight, 43 (83%) had hypertension or controlled hypertension, 23 (44%) had dyslipidemia, and 9 (17%) had hyperglycemia. Ten patients (19.2%) were diagnosed with metabolic syndrome. Twenty-eight patients (54%) had left ventricular hypertrophy. The prevalence of left ventricular hypertrophy was higher in patients with metabolic syndrome than in those without metabolic syndrome (90% vs 45%, P = 0.014), whereas estimated glomerular filtration rate did not differ between the 2 groups
	Kaur et al[9] (2018). Retrospective study	Recipients (18261) aged from 2 to 21 years	Normal weight population (11209 of 18261)	Obesity was associated with greater odds of delayed graft function (OR 1.3 95%CI: 1.13-1.49, P < 0.001), acute rejection (OR: 1.23 95%CI: 1.06-1.43, P < 0.01), and prolonged hospitalization (OR: 1.35 95%CI: 1.17-1.54, P < 0.001) as well as greater hazard of graft failure (HR: 1.13 95%CI: 1.05-1.22, P = 0.001) and mortality (HR: 1.19 95%CI: 1.05-1.35, P < 0.01). The overweight cohort had an increased risk of graft failure (HR: 1.08 95%CI: 1.001-1.16, P = 0.048) and increased odds of delayed graft function (OR: 1.2 95%CI: 1.04-1.38, P = 0.01) and acute rejection (OR: 1.18 95%CI: 1.01-1.38, P = 0.04)
	Sgambat et al[30] (2018). Longitudinal study	Recipients (42) aged from 3 to 20 years	Healthy children (24)	The longitudinal strain of transplant group was worse than controls at all time points (P < 0.001). Hemodialysis was independently associated with 21% worse longitudinal strain during the pre-transplant period (P = 0.04). After transplantation, obesity, MS, and systolic hypertension predicted increased odds of left ventricular hypertrophy (P < 0.04). Worse longitudinal strain was independently associated with obesity, MS, hypertension, and the combination of MS with elevated low density lipoprotein cholesterol (P < 0.04), whereas higher estimated glomerular filtration rate conferred a protective effect (P < 0.001)
	Ladhani et al[31] (2017). Retrospective study	Recipients (750) aged from 8 to 18 years	Normal weight population (129 of 750)	102 (16.2%) experienced acute rejection within the first 6 months of transplantation, 235 (31.3%) lost their allograft and 53 (7.1%) died. Compared to children with normal BMI, the adjusted HR for graft loss in children who were underweight, overweight or diagnosed as obese were 105 (95%CI: 0.70-1.60), 1.03 (95%CI: 0.71-1.49) and 1.61 (95%CI: 1.05-2.47), respectively. There was no statistically significant association between BMI and acute rejection (underweight: HR 1.07, 95%CI: 0.54-2.09; overweight: HR: 1.42, 95%CI: 0.86-2.34; obese: HR: 1.83, 95%CI: 0.95-3.51) or patient survival (underweight: HR: 1.18, 95%CI: 0.54-2.58, overweight: HR: 0.85, 95%CI: 0.38-1.92; obese: HR: 0.80, 95%CI: 0.25-2.61
	Hanevold et al[10]. Retrospective study	Recipients (6658) aged from 2 to 17 years	Normal weight population (6009 of 6658)	Obese children were significantly younger and shorter and had been on dialysis for a longer time than nonobese children. There was no significant difference in the overall patient and allograft survival between the 2 groups. However, obese children aged 6 to 12 years had higher risk for death than nonobese patients (adjusted relative risk: 3.65 for living donor; adjusted relative risk: 2.94 for cadaver), and death was more likely as a result of cardiopulmonary disease (27% in obese vs 17% in nonobese). Overall, graft loss as a result of thrombosis was more common in obese as compared with nonobese (19% vs 10%)
	Mitsnefes et al[32]. Retrospective study	Recipients (76) aged from 1.9 to 22.5 years	None	3 groups: (1) BMI > or = 95th; (2) BMI < 95th but became obese at 1 year after Tx; and (3) BMI < 95th percentile at time of Tx and 1 year later. Patients with BMI > or = 95th percentile doubled at 1 year after Tx when compared with pre-Tx data: 10 (13%) vs 22 (29%), respectively. Fifteen (20%) patients developed obesity and 10 (13%) patients had BMI between the 85th and 95th percentile at 1 year post Tx. Group 1 had significantly lower mean GFR [46.1+/-15.0 mL/min per 1.73 m(2)] than group 2 (57.7+/-24.5 mL/min per 1.73 m(2), P < 0.05) and group 3 (60.4+/-21.5 mL/min per 1.73 m(2), P < 0.01)

BMI: Body mass index; HR: Hazard ratio; OR: Odds ratio; MS: Metabolic syndrome; TX: Transplant; GFR: Glomerular filtration rate.