Comparison of different aspects of BMI history to identify undiagnosed diabetes in Japanese men and women: Toranomon Hospital Health Management Center Study 12 (TOPICS 12)

AimsTo examine current BMI and various aspects of BMI history as pre-screening tools for undiagnosed diabetes in Japanese individuals. MethodsThis cross-sectional study included 16 226 men and 7026 women aged 30-75 years without a self-reported history of clinician-diagnosed diabetes. We estimated the probability of having undiagnosed diabetes (fasting glucose 7.0 mmol/l and/or HbA(1c) 48 mmol/mol ( 6.5%) for the following variables: current BMI, BMI in the early 20s (BMI20y), lifetime maximum BMI (BMImax), change between BMI in the early 20s and current BMI (BMI20y-cur), change between BMI in the early 20s and maximum BMI (BMI20y-max), and change between lifetime maximum and current BMI (BMImax-cur). ResultsThe prevalence of undiagnosed diabetes was 3.3% (771/23252) among participants. BMImax, BMI20y-max and current BMI (1-sd increments) were more strongly associated with diabetes than the other factors (multivariate odds ratio 1.58 [95% CI 1.47-1.70] in men and 1.65 [95% CI 1.43-1.90] in women for BMImax; multivariate odds ratio 1.47 [95% CI 1.37-1.58] in men and 1.61 [95% CI 1.41-1.84] in women for BMI20y-max; multivariate odds ratio 1.47 [95% CI 1.36-1.58] in men and 1.63 [95% CI 1.40-1.89] in women for current BMI). The probability of having diabetes was markedly higher in those with both the highest tertile of BMImax and greatest BMI20y-max; however, a substantially lower likelihood of diabetes was observed among individuals with the lowest and middle tertiles of current BMI (< 24.62 kg/m(2) in men and < 22.54 kg/m(2) in women). ConclusionsLifetime maximum BMI and BMI changes from early adulthood were strongly associated with undiagnosed diabetes. Adding BMI history to people's current BMI would improve the identification of individuals with a markedly higher probability of having undiagnosed diabetes.