Endocrine Abstracts

Background: There is no existing longitudinal study to support ethnicity-specific and body mass index (BMI) category-specific waist circumference (WC) thresholds and their potential clinical utility to assess the risk of obesity-related diseases.

Methods: We performed a prospective assessment of 5,852,702 subjects in large-scale population-based cohort dataset obtained from the Korea National Health Insurance System. BMI was categorized into 6 subgroups (< 18.5, 18.5–22.9, 23.0–24.9, 25.0–29.9, 30.0–34.9, and ≥35.0 kg/m²). Time-dependent receiver operating characteristic curve analysis was used to determine BMI category-specific WC thresholds for predicting the development of type 2 diabetes and at least 1 other cardiometabolic risk factor (hypertension and/or dyslipidemia).

Results: During a mean follow-up of 8.2 years, 130,106 subjects were diagnosed with the main outcomes. The optimal BMI category-specific WC thresholds for men were determined to be 73, 79, 84, 89, 98 and 104 cm from the lowest to highest BMI categories. The corresponding values for women were 66, 72, 78, 83, 90 and 100 cm, respectively. Compared with the recommended single WC thresholds (men, 90 cm; women, 85 cm), the BMI category-specific WC thresholds showed an improved balance between sensitivity and specificity for all BMI categories, particularly for normal-weight and overweight individuals. In all BMI and WC categories, there was a significant increase in the hazard ratios for incident type 2 diabetes and comorbidities in proportion to the increases in WC thresholds for the given BMI categories (P < .001, respectively).

Conclusions: We determined optimal BMI category-specific WC thresholds, which provide additional information with which to identify individuals at a high risk of developing type 2 diabetes and comorbidities.