Effect of Pretransplant Body Mass Index on Kidney Transplant Recipient and Graft Long-term Survival

The aim of the study was to assess the influence of pretransplant body mass index (BMI [calculated as weight in kilograms divided by height in meters squared]) to the graft and patient 5- and 10-year survival.

Our study group consisted of 706 patients who received their kidney transplant after the year 2000.

Almost half, 51.9% (n = 372) of the patients had BMI < 25, and 47.6% (n = 336) had BMI ≥ 25. Patients who were overweight or obese were significantly older than other groups (P = .01). The 5-year recipient survival was significantly better in the BMI < 25 group (n = 291, 79.5%) than the BMI ≥ 25 group (n = 238, 70.2%, P < .05). In addition, 10-year recipient survival was better in the BMI < 25 group (n = 175, 47.8%) compared with the BMI ≥ 25 group (n = 127, 37.5%, P < .05). Similarly, 5-year graft survival was better in the BMI < 25 group (66.9%, n = 242) compared with the BMI ≥ 25 group (61.1%, n = 204, P < .05). However, 10-year graft survival was not statistically significant (P = .08). Regarding the impact of diabetes on survival, we found patients with diabetes mellitus to have worse survival in all groups (P = .009).

Recipient graft survival was affected by diabetes mellitus independently from being overweight. In the current study, we demonstrated that pretransplant obesity or being overweight affects recipient and graft short-term survival, but long-term comparison of patients who were overweight or obese with patients with normal BMI revealed minimal recipient survival differences and in graft survival analysis no difference. Although in many studies obesity and being overweight predict a bad outcome for kidney transplant recipient survival, our research did not fully confirm it. Diabetes mellitus had worse outcome in all patients groups.