title: Association between the Mediterranean diet and cognitive decline in a biracial population.
abstract: BACKGROUND
  Results from numerous studies suggest protective effects of the Mediterranean diet for cardiovascular disease, cancer, and mortality. Evidence for an association with a decreased risk of cognitive decline is less consistent and studies are limited by a lack of diversity in their populations.
  
  
  METHODS
  We followed 2,326 older adults (38.2% black, 51.3% female, aged 70-79 at baseline) over 8 years in a prospective cohort study in the United States (Health, Aging and Body Composition study). To measure adherence to a Mediterranean diet, we calculated race-specific tertiles of the MedDiet score (range: 0-55) using baseline food frequency questionnaires. Cognitive decline was assessed using repeated Modified Mini Mental State Examination scores over the study. We used linear mixed models to assess the association between MedDiet score and trajectory of cognitive decline.
  
  
  RESULTS
  Among blacks, participants with high MedDiet scores had a significantly lower mean rate of decline on the Modified Mini Mental State Examination score compared with participants with lower MedDiet scores (middle and bottom tertiles). The mean difference in points per year was 0.22 (95% confidence interval: 0.05-0.39; p = .01) after adjustment for age, sex, education, body mass index, current smoking, physical activity, depression, diabetes, total energy intake, and socioeconomic status. No association between MedDiet scores and change in Modified Mini Mental State Examination score was seen among white participants (p = .14).
  
  
  CONCLUSIONS
  Stronger adherence to the Mediterranean diet may reduce the rate of cognitive decline among black, but not white older adults. Further studies in diverse populations are needed to confirm this association and pinpoint mechanisms that may explain these results.
authors.affiliation: Northern California Institute For Research and Education, San Francisco. San Francisco VA Medical Center, California. akk412@mail.harvard.edu.
authors.forename: Alain
authors.initials: A
authors.lastname: Koyama
authors.affiliation: Sticht Center on Aging, Wake Forest University School of Medicine, Winston-Salem, North Carolina.
authors.forename: Denise K
authors.initials: DK
authors.lastname: Houston
authors.affiliation: Intramural Research Program, National Institute on Aging, Baltimore, Maryland.
authors.forename: Eleanor M
authors.initials: EM
authors.lastname: Simonsick
authors.affiliation: University of Georgia, Athens.
authors.forename: Jung Sun
authors.initials: JS
authors.lastname: Lee
authors.affiliation: Department of Epidemiology and Biostatistics, University of California San Francisco.
authors.forename: Hilsa N
authors.initials: HN
authors.lastname: Ayonayon
authors.affiliation: S. Daniel International Center for Health and Nutrition, Department of Epidemiology and Health Evaluation, Faculty of Health Sciences, Ben-Gurion University of the Negev, Israel.
authors.forename: Danit R
authors.initials: DR
authors.lastname: Shahar
authors.affiliation: Graduate School of Public Health, University of Pittsburgh, Pennsylvania.
authors.forename: Caterina
authors.initials: C
authors.lastname: Rosano
authors.affiliation: University of Tennessee Health Science Center, Memphis.
authors.forename: Suzanne
authors.initials: S
authors.lastname: Satterfield
authors.affiliation: San Francisco VA Medical Center, California. Department of Epidemiology and Biostatistics, University of California San Francisco. Departments of Psychiatry and Neurology, University of California San Francisco.
authors.forename: Kristine
authors.initials: K
authors.lastname: Yaffe
mesh_terms: D001741:Black or African American / Q000706:statistics & numerical data*; D000368:Aged; D003072:Cognition Disorders / Q000208:ethnology*; D015331:Cohort Studies; D038441:Diet, Mediterranean / Q000208:ethnology*; D005260:Female; D015438:Health Behavior / Q000208:ethnology; D006801:Humans; D008019:Life Style / Q000208:ethnology; D008297:Male; D012959:Socioeconomic Factors; D014481:United States; D044465:White People / Q000706:statistics & numerical data*
keywords: Alzheimers; Cognition.; Cognitive aging; Epidemiology; Nutrition