Impact of body mass index on 30-day postoperative morbidity in pediatric and adolescent patients undergoing continent urinary tract reconstruction.

Introduction: Obesity has been thought to increase the risk of complications and need for additional resources with surgery, but only a limited amount of evidence is available in the pediatric population.

Objective: The objectives were to describe the weight status of pediatric and adolescent patients undergoing a continent urinary tract reconstruction and to determine the association between obesity and 30-day postoperative morbidity.

Study Design: A retrospective cohort study was performed for pediatric and adolescent patients aged up to 20 years who underwent a continent urinary tract reconstruction between January 2010 and November 2016. Weight status was stratified by the body mass index (BMI) for age z-scores as follows: underweight (<5th percentile), normal (5th to <85th percentiles), overweight (85th to <95th percentiles), and obese (≥95th percentile). Primary outcomes included the duration of intensive care and hospitalization as well as re-admissions and complications within 30 days.

Results: A total of 182 continent reconstructions were identified during the study period. Demographic and peri-operative data are provided in the Table. Weight status was not associated with any primary outcomes on univariate or multivariate analysis. There was also no association in an analysis between the non-overweight or non-obese group (BMI for age z-score <85th) and overweight or obese group (BMI for age z-score ≥85th percentiles); a subgroup analysis between patients with and without myelomeningocele; or a subgroup analysis for wound, infectious, or high-grade (Clavien-Dindo grades III or higher) complications.

Discussion: Obesity has been consistently associated with an increased risk of surgical site infections and wound complications after a wide variety of surgeries in adults. The results from the present study conflict with those of the few available studies in the pediatric population. The high-risk nature of the present cohort may have mitigated any effect of obesity on 30-day postoperative morbidity. The limitations of the present study include its retrospective design at a single center and the potential misclassification of weight status with the BMI.

Conclusions: Almost 30% of pediatric and adolescent patients undergoing a continent urinary tract reconstruction were overweight or obese. Obesity as determined by the BMI was not associated with 30-day postoperative morbidity.