Background: Obese individuals with normal metabolic profiles, so-called “metabolically healthy obese (MHO)” status has shown better clinical outcomes via previous studies. However, studies dealing with the association between MHO and dementia, which is deeply associated with metabolic disorders, were still insufficient. We designed this study to assess the association between MHO and the risk of incident dementia.

Methods: The present study is a retrospective cohort study, including 5,669,488 patients aged 60 years old or over without any history of dementia, by using the National Health Insurance System of South Korea. Subjects were divided into 4 groups based on their metabolic health and obesity status. Metabolic health was determined based on the criteria of metabolic syndrome by Adult Treatment Panel-III. Obesity was judged based on the baseline body mass index. The incidence of dementia was checked and compared longitudinally between 4 groups.

Results: When we put the metabolically healthy non-obese group to the reference value (hazard ratio (HR) = 1), MHO group showed the lowest incidence of dementia (HR 0.87, 95% confidence interval (CI) 0.86-0.88). This trend was more prominent when we followed up the risk of Alzheimer’s disease as a subgroup analysis (HR 0.85, 95% CI 0.83-0.86). Non-obese subjects with metabolic syndrome showed significantly increased risk for overall dementia (HR 1.20, 95% CI 1.19-1.21), especially for vascular dementia (HR 1.41, 95% CI 1.38-1.45).

Conclusion: MHO status was associated with lower risk for dementia, especially for Alzheimer’s disease.


J. Bae: None. J. Lee: None. Y. Cho: None. M. Lee: None. S. Lee: None. I. Lee: None. E. Kang: None. S.J. Cho: None. K. Han: None. B. Cha: None. Y. Lee: None.

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