Evaluation of Surgical Morbidity After Hysterectomy During an Obesity Epidemic

To assess 30-day outcomes for hysterectomy by body mass index (BMI) classification and estimate trends in 30-day outcomes by BMI over time.

This is a retrospective cohort study of patients older than age 18 years undergoing hysterectomy with data in the National Surgical Quality Improvement Program database from 2005 to 2018. Exclusions were made for ambiguous indication or route of surgery and missing values in covariates or outcomes of interest. Patient characteristics and outcomes were compared across BMI classifications. Outcomes included operative time, length of stay, and major and minor complications. Multivariable linear regression models were used for continuous outcomes, and modified Poisson regression models were used for binary outcomes. Patients with benign and malignant indications for hysterectomy were analyzed separately. Models were adjusted for age, race, hysterectomy route, hypertension, diabetes, smoking, selected preoperative laboratory values, and cancer type, if applicable.

Obesity rate increased from 41.2% in 2005-2007 to 51.8% in 2018. Among 319,462 patients, minimally invasive surgery was the most common approach (58.8% vs 24.5% laparotomy vs 16.7% vaginal). Higher BMI classifications were associated with longer operative times (benign indication: average 25.0 minutes longer, 95% CI 22.1-27.9; malignant indication: average 25.1 minutes longer, 95% CI 20.8-29.4) and higher risk of complications compared with normal-weight BMIs, though operative time declined over time for patients with malignant surgical indications. Relative to normal-weight patients, rates of major complications did not increase until a BMI of 40 for hysterectomy for benign indications and 50 for hysterectomy for malignant indications.

Operative times and complications both increase with obesity when performing hysterectomy. Knowledge of evolving risk level at various weight subclassifications can improve shared decision making preoperatively.