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

BACKGROUND: 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. METHODS: Our study group consisted of 706 patients who received their kidney transplant after the year 2000. RESULTS: 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). CONCLUSIONS: 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.

Ultrasound elastography correlations between anthropometrical parameters in kidney transplant recipients.

Ultrasound elastography (USE) is a method to assess the stiffness of parenchymatous organs. Shear wave elastography (SWE) is considered to be the most suitable elastography method for the non-invasive kidney transplant (KTx) elasticity assessment. The aim of this study was to assess the implementability of SWE for the evaluation of kidney transplant elasticity measurement depending on the depth of an allograft, body mass index (BMI) and donor age. Secondly, to investigate the associations between SWE stiffness measurements and the clinical parameters. This cross-sectional prospective study involved consecutive 100 KTx patients were grouped according to time from transplantation and their BMI (in BMI<25 group the mean was 22.1±2.4, n=42 and in BMI≥25 group the mean BMI was 29.9±3.3, n=58). Mean estimated glomerular filtration rate was almost similar in both groups: <25 group 54.3 and ≥25 group 53.4 mL/min. Mean elastography results were found statistically different (p=0.006) BMI<25 (8.95±5.84 kPa) and BMI≥25 (5.95±3.16 kPa) groups. Significant correlation was found between SWE and the depth of the measurement (r=-0.4, p<0.05). The variations in USE stiffness values were smallest in patients group with lower BMI. In conclusion, we demonstrated that the non-invasive USE measurement stiffness result depends on a patient's BMI, the depth of renal allograft and donor age.