Does BMI Impact Outcomes in Patients Undergoing Open Abdominal Wall Reconstruction? A Systematic Review and Meta-Analysis

Abstract

Importance: Obesity is a significant factor that increases complication rates in patients undergoing abdominal wall reconstruction (AWR). This has led to caution about performing elective AWR in patients with higher body mass index (BMI). In light of this, our study aims to synthesize the current information on AWR outcomes in patients stratified according to the obesity classification, providing evidence-based insights into the impact of BMI on AWR outcomes.

Objective: To compare the clinical outcomes in patients of different BMI groups undergoing AWR.

Data sources: A systematic literature search of two databases (PubMed and Cochrane CENTRAL) from January 1st, 1966, until July 31, 2024, identified five relevant studies.

Study selection: Included in our analysis were original studies that assessed clinical outcomes in patients with a BMI < 35 kg/m² compared to those with a BMI ≥ 35 kg/m² undergoing elective AWR. Studies with a patient population of less than 18 years or oncologic patient population were excluded.

Data extraction and synthesis: This systematic review and meta-analysis are reported as per the PRISMA statement. As recommended by the Cochrane Collaboration, the Newcastle-Ottawa scale was used to evaluate methodological quality. The Mantel-Haenszel random-effects method was used to calculate the pooled odds ratios (ORs) with their 95% confidence intervals (CIs).

Main outcome: The primary outcomes were hernia recurrence, readmission, reoperation, and surgical site infection (SSI).

Results: Out of 4769 classifiable patients that underwent AWR, the majority were obese- CDC Class 1, 2 (2401; 50%) or morbidly obese-Class 3 (1054; 22%). Patients with a BMI < 35 kg/m² compared to a BMI ≥ 35 kg/m² were associated with significantly decreased odds of readmission (OR 0.52, 95% CI 0.38-0.70, I² = 0%, and p < 0.0001), reoperation (OR 0.72, 95% CI 0.55-0.93, I² = 17%, and p = 0.01), and developing SSI (OR 0.62, 95% CI 0.48-0.81, I² = 35%, and p = 0.0005), whereas hernia recurrence (OR 1.03, 95% CI 0.35-3.00, I² = 88%, and p = 0.96) was statistically insignificant.

Conclusion and relevance: A patient's BMI should not be the sole determinant when planning elective AWR, as increasing BMI does not impact hernia recurrence rates. However, obese patients should be counseled on the higher risk of developing infections, requiring reoperation, and necessitating readmission due to their weight.

Keywords: BMI; abdominal wall reconstruction; complex ventral hernia repair; obesity; recurrence.

FIGURE 1

PRISMA flowchart of included studies.

FIGURE 2

Forest plot of (A) hernia recurrence, (B) readmission, (C) reoperation, and (D) surgical site infection stratified by a BMI < 35 kg/m² and a BMI ≥ 35 kg/m².