Association Between Mediterranean Diet and Functional Status in Older Adults: A Longitudinal Study Based on the Washington Heights-Inwood Columbia Aging Project

BACKGROUND: Current evidence on the association between Mediterranean diet (MeDi) intake and activities of daily living (ADL) is limited and inconsistent in older adults.
METHODS: This study included 1 696 participants aged ≥65 years in the Washington Heights-Inwood Community Aging Project study. The MeDi score was calculated based on data collected from the Willett’s semiquantitative food frequency questionnaire. The multivariable-adjusted Cox regression model was applied to examine the association of MeDi score with risks of disability in basic (BADL) and instrumental ADL (IADL), as well as the overall ADL (B-IADL).
RESULTS: Eight hundred and thirty-two participants with incident ADL disability were identified over a median follow-up of 5.39 years. The continuous MeDi score was significantly associated with decreased risk of disability in B-IADL (hazard ratio = 0.95, 95% confidence interval = 0.91-0.99, p = .018) in a model adjusted for age, sex, race/ethnicity, educational level, and dietary calories intake but was no longer significant after additionally adjusted for multiple comorbidities and physical activities (0.97 [0.93, 1.01], p = .121). The continuous MeDi score was significantly associated with decreased risk of disability in B-IADL (0.92 [0.85, 1.00], p = .043) and BADL (0.90 [0.82, 0.99], p = .030) in non-Hispanic Whites, but not in non-Hispanic Blacks and Hispanics (p > .05 for all).
CONCLUSIONS: Higher MeDi score was associated with decreased risk of ADL disability, particularly in non-Hispanic Whites.