Adherence to a Mediterranean Diet, Cognitive Decline, and Risk of Dementia

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Study today published in JAMA

The Journal of the American Medical Association (JAMA)

Vol. 302 No. 6, August 12, 2009

Adherence to a Mediterranean Diet, Cognitive Decline, and Risk of Dementia

Féart, PhD; Cécilia Samieri, MPH; Virginie Rondeau, PhD; Hélène

Amieva, PhD; Florence Portet, MD, PhD;

Jean-François Dartigues, MD, PhD; Nikolaos Scarmeas, MD; Pascale

Barberger-Gateau, MD, PhD

JAMA. 2009;302(6):638-648.

Context: Higher adherence to a Mediterranean-type diet is linked to lower risk

for mortality and chronic diseases, but its association with cognitive decline

is unclear.

Objective: To investigate the association of a Mediterranean diet with change

in cognitive performance and risk for dementia in elderly French persons.

Design, Setting, and Participants: Prospective cohort study of 1410 adults

( & #8805;65 years) from Bordeaux, France, included in the Three-City cohort in

2001-2002 and reexamined at least once over 5 years. Adherence to a

Mediterranean diet (scored as 0 to 9) was computed from a food frequency

questionnaire and 24-hour recall.

Main Outcome Measures: Cognitive performance was assessed on 4

neuropsychological tests: the Mini-Mental State Examination (MMSE), Isaacs Set

Test (IST), Benton Visual Retention Test (BVRT), and Free and Cued Selective

Reminding Test (FCSRT). Incident cases of dementia (n = 99) were validated by an

independent expert committee of neurologists.

Results: Adjusting for age, sex, education, marital status, energy intake,

physical activity, depressive symptomatology, taking 5 medications/d or more,

apolipoprotein E genotype, cardiovascular risk factors, and stroke, higher

Mediterranean diet score was associated with fewer MMSE errors ( & #946; = –0.006;

95% confidence interval [CI], –0.01 to –0.0003; P = .04 for 1 point of the

Mediterranean diet score). Performance on the IST, BVRT, or FCSRT over time was

not significantly associated with Mediterranean diet adherence. Greater

adherence as a categorical variable (score 6-9) was not significantly associated

with fewer MMSE errors and better FCSRT scores in the entire cohort, but among

individuals who remained free from dementia

over 5 years, the association for the highest compared with the lowest group was

significant (adjusted for all factors, for

MMSE: & #946; = –0.03; 95% CI, –0.05 to –0.001; P = .04; for FCSRT: & #946; =

0.21; 95% CI, 0.008 to 0.41; P =.04). Mediterranean diet

adherence was not associated with the risk for incident dementia (fully adjusted

model: hazard ratio, 1.12; 95% CI, 0.60 to

2.10; P = .72), although power to detect a difference was limited.

Conclusions: Higher adherence to a Mediterranean diet was associated with

slower MMSE cognitive decline but not consistently with other cognitive tests.

Higher adherence was not associated with risk for incident dementia.

Author Affiliations: Research Center INSERM U897, Université Victor Segalen

Bordeaux 2, Bordeaux, France (Drs Féart, Rondeau, Amieva, Dartigues, and

Barberger-Gateau and Ms Samieri); INSERM U888, Université Montpellier 1,

Montpellier, France (Dr Portet); and Department of Neurology, Columbia

University Medical Center, New York, New York (Dr Scarmeas).