Independent Impact of Body Mass Index and Metabolic Syndrome on the Risk of Type 2 Diabetes in Koreans

Abstract

Background:

Although obesity and metabolic syndrome have been associated with the risk of type 2 diabetes mellitus (T2DM), it is unclear whether obese or overweight people without metabolic syndrome are at increased risk for T2DM.

Methods:

Clinical and laboratory data were assessed in 8,748 subjects without diabetes (5,707 men, 3,041 women; age 20–79 years) who underwent voluntary medical check-ups at a 5-year interval. The subjects were categorized by body mass index (BMI) and metabolic syndrome status at baseline, and the incidence of diabetes over 5 years was assessed.

Results:

Of the 8,748 subjects, 308 (3.5%) developed T2DM over 5 years. Compared with normal weight (BMI <25.0 kg/m²) individuals without metabolic syndrome, the adjusted odds ratios (ORs) were 1.61 (1.13–2.29) and 4.93 (1.90–12.79) for overweight (BMI 25.0–29.9 kg/m²) and obese (BMI ≥30.0 kg/m²) individuals without metabolic syndrome, respectively, and 6.94 (5.08–9.47) and 10.61 (5.59–20.14) for overweight and obese individuals with metabolic syndrome, respectively. Using the lower BMI cutoff points for Asian populations, compared with subjects with BMI <23 kg/m² without metabolic syndrome, the adjusted ORs for subjects with BMI 23–27.4 kg/m² and BMI ≥27.5 kg/m² without metabolic syndrome were 2.64 (1.74–4.00) and 4.31 (2.36–7.86), respectively, and 10.11 (6.53–15.67) and 16.69 (10.40–26.77), respectively, for those with metabolic syndrome.

Conclusions:

Overweight/obesity and metabolic syndrome both are significant risk factors for development of T2DM in Koreans, and overweight or obesity without metabolic syndrome should not be considered a harmless condition. The lower BMI cutoffs for Asian populations can be useful in predicting risk of T2DM in Koreans.