The impact of obesity on outcomes for patients undergoing mastectomy using the ACS-NSQIP data set

According to the World Health Organization (WHO), 34.7% of females in the United States are obese (BMI ≥ 30) in 2014, compared to 32.5% in 2010. The previous research has demonstrated high BMI as an independent risk factor for surgical complications after breast surgery. As more patients become obese, we sought to examine whether increasing obesity had an effect on outcomes of women who underwent a unilateral mastectomy without breast reconstruction.

The study reviewed the 2007-2012 ACS-NSQIP database and identified all patients who underwent a unilateral mastectomy without reconstruction. Patients were then categorized and compared according to the World Health Organization obesity classification. Data were analyzed for minor complications (e.g., UTI and SSI) and major complications (e.g., renal failure, sepsis, deep vein thrombosis, return to operating room [RTOR], and cardiac arrest).

A total of 7207 women were identified. Median BMI was 27.3 kg/m². From the cohort, 453 patients (6.29%) had a major complication and 173 patients (2.40%) had a minor complication. 53 (0.74%) had bleeding complications, 148 (2.05%) had a surgical site infection (SSI), 352 (4.88%) RTOR, and 7 (0.01%) died within 30 days. Major complications (p = 0.005) and minor complications (p < 0.001) significantly increased as BMI increased. SSI and RTOR had increasing trends, but were not statistically significant.

This study characterizes the risk of complications in women undergoing unilateral mastectomies and shows that increasing obesity is associated with major and minor postoperative complications. Our finding highlights the need for personalized preoperative risk assessment and counseling of obese patients.