The Influence of Obesity and Fibrosis in Live Donor Kidney Transplantation

Introduction: Donor obesity has increased over the last decade. Although only a small number of obese patients develop chronic kidney disease, there might be a subclinical pathological process in the majority of them. The aim of this study was to assess the effect of donor obesity on fibrosis in pre-implantation biopsy and kidney outcomes in live kidney transplants. 

Methods:A series of 288 live kidney donors between 1998 and 2010 were studied. The series was divided into three groups according to the donor Body Mass Index (BMI); Normal BMI 17 - 24.9 (n = 119), overweight BMI 25 – 29.9 (n = 118) and obese BMI ≥ 30 (n = 51). Donor and recipient demographics were gathered and recipient post-transplant renal function up to five years was retrieved. Fibrosis level in pre-implantation biopsies was analysed and graft and recipient survival were assessed. Results: Hypertension and live kidney donor profile index LKDPI were statistically significantly higher in obese donors compared with non-obese donors (p=0.004 and p<0.001 respectively). Donor creatinine levels for obese group were comparable to the other two groups over three post-operative years (p=0.933). Fibrosis analysis showed no statistically significant difference among the three BMI groups (p=0.063). Donor obese group had statistically significant higher 5 year graft and patient loss rate compared with non-obese BMI groups (p=0.018 and p=0.015 respectively). Recipient post-operative creatinine levels showed no statistically significant differences among the three BMI groups (p=0.393). Similarly, fibrosis in pre-implantation biopsies had no statistically significant impact on recipient post-operative creatinine levels (p=0.243). 

Discussion: Donor obesity has no significant impact on fibrosis in the pre-implantation biopsy and on recipient post-operative kidney function. However, Donor obesity results in lower five-year graft and patient survival rate and this should be discussed with both donor and recipient in the pre-operative stage to facilitate decision making.