Cognitive measures predict pathologic Alzheimer disease

Background: Neuropsychologic testing is often used to infer neuropathologic processes, but clinicopathologic correlations for individual cognitive measures are based on a small number of published studies. Objective: To examine the usefulness of the age- and education-adjusted Mayo Cognitive Factor Scales (MCFS) obtained at participants' initial assessments for predicting the presence or absence of pathologic Alzheimer disease (AD). Design: This was a longitudinal study of a cohort of elderly patients with and without cognitive complaints who were followed up until death. Mayo Cognitive Factor Scales age- and education-adjusted standard scores from the participants' initial evaluations were used to calculate classification accuracy statistics for neuropathologic AD diagnosis obtained approximately 6 years after testing. Subjects with non-AD diagnoses or substantial non-AD-related changes were excluded from the study. Setting: Academic medical center. Participants: One hundred two participants were evaluated clinically and underwent neuropathologic examination at autopsy. All were part of the Mayo Clinic Alzheimer's Disease Patient Registry or Alzheimer Disease Research Center. Results: All Mayo Cognitive Factor Scale scores were significantly correlated with AD criteria. Logistic regression modeling including Mayo Cognitive Factor Scales Verbal Comprehension and Retention indices revealed high positive predictive value with moderate sensitivity and specificity for pathologic AD. Conclusion: Neuropsychologic test scores at initial evaluations were predictive of pathologic AD.