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The relationship between BMI and pediatric postoperative outcomes: a 12-year NSQIP-P analysis
Josélio Rodrigues de Oliveira Filho1,2, Ikemsinachi C Nzenwa3, Michael A Kochis1,2
1Department of Pediatric Surgery, Massachusetts General Hospital, Boston, MA, USA.
Insights
Childhood obesity is not a contraindication for surgery, as higher BMI was linked to better outcomes. Conversely, underweight children had worse postoperative results, suggesting a need for nutritional optimization.
Area of Science:
- Pediatric Surgery
- Clinical Outcomes Research
- Obesity Medicine
Background:
- Childhood obesity prevalence is rising, posing potential risks for surgical complications.
- Understanding the impact of Body Mass Index (BMI) on pediatric surgical outcomes is crucial for clinical decision-making.
- This study investigated the association between BMI and postoperative outcomes in children undergoing various surgical procedures.
Purpose of the Study:
- To analyze the relationship between pediatric Body Mass Index (BMI) categories and postoperative outcomes.
- To determine if elevated BMI influences surgical complication rates in children.
- To guide surgical practice regarding the management of pediatric patients with varying BMI.
Main Methods:
- A cohort study included 373,315 pediatric patients (aged 2-18) undergoing general, urological, or gynecological procedures from 2012-2023.
- Patients were categorized by BMI (underweight, normal, overweight, and obesity classes I-III) using American Academy of Pediatrics and CDC guidelines.
- The primary outcome was the Desirability of Outcome Ranking (DOOR), a composite measure of 22 postoperative events, analyzed using ordinal logistic regression.
Main Results:
- Higher BMI categories (Class II and III obesity) were paradoxically associated with more favorable DOOR scores (fewer complications) after adjusting for clinical risk.
- Underweight status was consistently linked to less desirable postoperative outcomes (OR 1.08, 95% CI 1.04-1.12).
- In elective general surgery, obesity (Class II and III) showed protective effects, while underweight status predicted worse outcomes in non-elective general surgery.
Conclusions:
- Elevated BMI in children is not necessarily a risk factor and may be associated with better surgical outcomes.
- Extremely low BMI is a significant predictor of less favorable postoperative results in pediatric surgery.
- Optimizing nutritional status in underweight children presents a key opportunity to improve surgical outcomes.
Background:
Childhood obesity is increasingly prevalent and historically considered a risk factor for surgical complications. Evaluating the influence of body mass index (BMI) on pediatric surgical outcomes is critical for guiding care. This study aimed to examine the relationship between BMI and postoperative outcomes in children.
Methods:
Cohort study of patients aged 2-18 years undergoing general surgical, urological, or gynecological procedures at National Surgical Quality Improvement Program-Pediatric hospitals (2012-2023). The exposure was BMI categories defined by American Academy of Pediatrics and Centers for Disease Control and Prevention. The primary outcome was the Desirability of Outcome Ranking (DOOR), a composite measure of 22 postoperative events ranked from 1 (no complication) to 6 (worst complications). Ordinal logistic regression models, adjusted for clinical risk, assessed the association between BMI and DOOR.
Results:
Among 373,315 patients (mean age 10.8 ± 4.7 years; 54.2% male), 7.1% were underweight, 55.1% normal weight, 15.1% overweight, 12.3% class I obesity, 6.0% class II obesity, and 4.3% class III obesity. Unadjusted analyses showed fewer complication-free courses (DOOR score 1) in underweight children, while class II-III obesity had the highest proportion of complication-free courses. In adjusted analyses, underweight was associated with worse DOOR scores (OR 1.08, 95% CI 1.04-1.12) while Class II (OR 0.89, 95% CI 0.85-0.94) and class III obesity (OR 0.76, 95% CI 0.71-0.81) were protective. Subgroup analyses showed that in elective general surgery, class II (OR 0.79, 95% CI 0.73-0.86) and class III obesity (OR 0.65, 95% CI 0.59-0.72) remained protective, whereas in non-elective general surgery, underweight status was still predictive of worse DOOR scores (OR 1.25, 95% CI 1.16-1.34).
Conclusion:
Extremely low BMI was consistently linked to less desirable postoperative outcomes, whereas obesity was paradoxically associated with more favorable DOOR scores. Elevated BMI alone should not be considered a contraindication to pediatric surgery. Efforts to optimize underweight children may offer the greatest opportunity to improve surgical outcomes.
