JMIR Publications

ABSTRACT

Background:

Studies have found associations between increasing body mass index (BMI) and the development of various chronic health conditions. The BMI cut-points, or thresholds beyond which comorbidity incidence can be accurately detected, are unknown.

Objective:

To identify whether BMI cut-points exist for 11 obesity-related comorbidities.

Methods:

U.S. adults aged 18-75 with 3 healthcare visits at an academic medical center from 2008-2016 were identified from the electronic health record. Pregnant, cancer, and bariatric surgery patients were excluded. Quantile regression with BMI as the outcome was used to evaluate associations between BMI and disease incidence. A comorbidity was determined to have a cut-point if the area under the receiver operating curve was > 0.6. The cut-point was defined as the BMI value that maximized Youden’s index.

Results:

We included 243,332 patients in the study cohort. The mean age and BMI were 46.8 years and 29.1 kg/m2, respectively. We found statistically significant associations between increasing BMI and the incidence of all comorbidities except for anxiety and cerebrovascular disease. Cut-points were identified for hyperlipidemia (27.1 kg/m2), coronary artery disease (27.7 kg/m2), hypertension (28.4 kg/m2), osteoarthritis (28.7 kg/m2), obstructive sleep apnea (30.1 kg/m2), and type 2 diabetes (30.9 kg/m2).

Conclusions:

The BMI cut-points that accurately predicted risks of developing 6 obesity-related comorbidities occurred when patients were overweight or barely met criteria for class 1 obesity. Further studies using national, longitudinal data are indicated to determine if screening guidelines for appropriate comorbidities may need to be revised.