Objectives: Although obese individuals without obesity related metabolic abnormalities are often defined as metabolically healthy, risks for developing such abnormalities have not been evaluated well. Recently, a prospective study showed that metabolically healthy obese subjects were at higher risk of diabetes, stroke and cardiovascular disease than metabolically healthy subjects without obesity in UK. We here analyzed the association between metabolically healthy obesity and a risk for developing diabetes in a Japanese population.

Research Design and Methods: The participants were recruited from Iwaki study, a health promotion study of Japanese people aimed to prevent lifestyle-related disease. Among 1167 participants of Iwaki study held in 2014, 931 individuals attended at least one time in 2015 to 2019. We excluded 7 and 75 individuals without complete data sets and who were diagnosed with diabetes in 2014 respectively, thus 849 subjects were enrolled in this study. Obesity was defined as BMI >25 kg/m2. We used the National Cholesterol Education Program ATP III Guideline to categorize metabolically unhealthy as participants meeting at least two criteria of metabolic abnormalities. Results: In 2014, the number of metabolically healthy subjects without and with obesity were 6 and 1 respectively. Cox proportional hazard model showed metabolically healthy subjects with obesity were at higher risk of diabetes compared with those without obesity (Hazard ratio 3.70, p=0.002) , even if after adjusted by age and sex (Hazard ratio 3.32, p=0.005) .

Conclusions: Our analysis suggest an importance of encouraging people with obesity to reduce body weight even though they are metabolically healthy. We are extending such analyses in association with other lifestyle-related diseases.


S.Mizushiri: None. M.Daimon: None. A.Kamba: None. M.Murabayashi: None. Y.Nishiya: None. R.Ito: None. A.Tamura: None. S.Ono: None. K.Matsuki: None.

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