In Reply: Dr Barberger-Gateau and I agree that diet is part of a larger ensemble of health-related behaviors that may have an effect on cognition and late-life dementia. However, he takes issue with my characterization of the associations between changes on the FCSRT and adherence to the Mediterranean diet in the study by Féart et al.1
Barberger-Gateau acknowledges that the associations with changes over time on this test and adherence to the Mediterranean diet were not seen in the principal analyses (Table 3 of the article). When participants with incident dementia were excluded (Table 6), the P value for the time × category (tertile) analysis for the FCSRT change was less than .05 even though the point estimate was the same as in the primary analyses. The differences in outcomes between results from primary analyses and subsequent exploratory analyses are therefore inconsistent. In contrast, the associations of changes on the MMSE and the Mediterranean diet were observed across a variety of analyses.
Knopman DS. Association Between Mediterranean Diet and Late-Life Cognition—Reply. JAMA. 2009;302(22):2433. doi:10.1001/jama.2009.1795