Meta-analysis of double blind randomized controlled clinical trials of acetyl-L-carnitine versus placebo in the treatment of mild cognitive impairment and mild Alzheimer??s disease :

We studied whether Mini-Mental State Examination (MMSE) norms for detecting dementia in elderly outpatients vary according to educational attainment. Subjects were 109 elderly outpatients with Alzheimer's dementia and 100 non-demented outpatient controls. Receiver operating characteristics (ROC) of the MMSE were examined among three strata of educational attainment: middle school, high school, and college/graduate school. MMSE ROC curve areas were .95-.96 in the three educational strata. Assuming a dementia prevalence of 10%-30%, the most accurate lower limits of normal for MMSE scores and their attendant sensitivities and specificities were 21 for middle school (.82/.94), 23 for high school (.79/.97), and 24 for college/graduate school (.83/1.00) attainment. These norms accurately classified over 90% of subjects in all three educational strata. We conclude that education-specific norms optimize performance of the MMSE as a screening test for Alzheimer's dementia in elderly outpatients.

Many studies have implicated low education as a risk factor for cognitive impairment in elderly people. Findings are, however, inconsistent and the mechanism by which education level may intervene in senescent cognitive change is uncertain. The present study examines cognitive change over a 1-year period in 283 elderly persons manifesting recent subclinical deterioration in at least one area of cognitive functioning. The results suggest that the impact of both education level and young adult IQ on the degree of cognitive change over the year is greater in the older age groups. Secondary memory and language functions were found to be more resistant to decline in the high-education group, while attention, implicit memory and visuospatial skills are found to decline irrespective of education level.