title: Body Mass Index and Decline of Cognitive Function.
abstract: BACKGROUND
  The association between body mass index (BMI) and cognitive function is a public health issue. This study investigated the relationship between obesity and cognitive impairment which was assessed by the Korean version of the Mini-mental state examination (K-MMSE) among mid- and old-aged people in South Korea.
  
  
  METHODS
  A cohort of 5,125 adults, age 45 or older with normal cognitive function (K-MMSE≥24) at baseline (2006), was derived from the Korean Longitudinal Study of Aging (KLoSA) 2006~2012. The association between baseline BMI and risk of cognitive impairment was assessed using multiple logistic regression models. We also assessed baseline BMI and change of cognitive function over the 6-year follow-up using multiple linear regressions.
  
  
  RESULTS
  During the follow-up, 358 cases of severe cognitive impairment were identified. Those with baseline BMI≥25 kg/m2 than normal-weight (18.5≤BMI<23 kg/m2) were marginally less likely to experience the development of severe cognitive impairment (adjusted odds ratio [aOR] = 0.73, 95% CI = 0.52 to 1.03; Ptrend = 0.03). This relationship was stronger among female (aOR = 0.63, 95% CI = 0.40 to 1.00; Ptrend = 0.01) and participants with low-normal K-MMSE score (MMSE: 24-26) at baseline (aOR = 0.59, 95% CI = 0.35 to 0.98; Ptrend<0.01). In addition, a slower decline of cognitive function was observed in obese individuals than those with normal weight, especially among women and those with low-normal K-MMSE score at baseline.
  
  
  CONCLUSIONS
  In this nationally representative study, we found that obesity was associated with lower risk of cognitive decline among mid- and old-age population.
authors: Takemi Program in International Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America.
authors: Sujin
authors: S
authors: Kim
authors: Department of Social and Behavioral Sciences, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America.
authors: Yongjoo
authors: Y
authors: Kim
authors: Takemi Program in International Health, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America.|Department of Family Medicine & Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, South Korea.
authors: Sang Min
authors: SM
authors: Park
mesh_terms: D000368:Aged; D000375:Aging; D001823:Body Composition; D015992:Body Mass Index; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000150:complications*; D005260:Female; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009765:Obesity / Q000150:complications*; D016017:Odds Ratio; D011446:Prospective Studies; D056910:Republic of Korea