BMI Not an Important Predictive Factor When Predicting Mortality of Obese Patients

Body mass index (BMI) is not an important factor in calculating the all-cause 10-year mortality in obese patients eligible for bariatric surgery, researchers found while constructing a new mortality prediction rule.

While BMI was found to be significantly predictive (OR 1.03, 95% CI 1.01-1.05), it was the least predictive risk factor, according to Raj Padwal, MD, MSC, of the University of Alberta in Edmonton, and colleagues.

In an attempt to identify important mortality predictors and verify the importance of BMI, researchers analyzed data from 15,394 obese English patients who met eligibility criteria for bariatric surgery (BMI of 35 or greater, or BMI of 30-34.9 with an obesity-related comorbidity) from 1988 to 1998.

Comorbidities included hypertension, dyslipidemia, heart failure, diabetes, sleep apnea, osteoarthritis, coronary artery disease, and cerebrovascular disease.

Researchers found that “all-cause 10-year mortality in obese individuals eligible for bariatric surgery can be estimated using a simple 4-variable prediction rule based on age, sex, smoking, and diabetes mellitus. Body mass index was not an important mortality predictor. “

“Further work is needed to define low, moderate, and high absolute risk thresholds and to provide external validation,” they concluded.

–Michael Potts

Reference

Padwal R, Klarenbach S, Wang X, Sharma A, et al. A Simple Prediction Rule for All-Cause Mortality in a Cohort Eligible for Bariatric Surgery [published online ahead of print October 16, 2013. JAMA doi:10.1001/jamasurg.2013.3953