Retrospective Study of Effects of Preoperative BMI on Early Outcomes in Recipients After Kidney Transplant

Background: The objective of this retrospective study was to establish the effect of the preoperative body mass index (BMI) on early outcomes of recipients after a kidney transplant, including liver and kidney function and fasting blood glucose recovery.

Methods: Our analytical cohort were patients who had undergone a kidney transplant at The First Affiliated Hospital of USTC [2016-2019]. The BMI classifications were underweight (<18.5 kg/m²), normal weight (18.5-23.9 kg/m²), and overweight or obese (≥24 kg/m²). A χ² test was conducted to compare differences between the patients in the different BMI groups.

Results: We enrolled 831 recipients in the study. The percentage of patients with normal serum creatinine and normal urea nitrogen in the BMI ≥24 group was lower at different periods after surgery (P<0.05). The percentage of patients with normal uric acid in the normal weight group was higher on day 1 and the first week after surgery (P < 0.001). In the first and second weeks postsurgery, the percentage of patients with aspartate transaminase/alanine aminotransaminase in the BMI ≥24 group was lower (P < .005). In the first week postsurgery, the percentage of patients with normal albumin/globulin in the normal weight group was higher (P < .05). No statistically significant difference among the 3 groups was found in the incidence of hyperglycemia (P > .05).

Conclusions: The patients who were overweight or obese preoperatively had poorer renal and liver functions postoperatively. Targeted interventions to control or mitigate rates of overweight or obesity preoperatively should be identified.