Sex-Specific Cutoffs for Mild Cognitive Impairment Improve Diagnostic Accuracy

By Reuters Staff

October 22, 2019

NEW YORK (Reuters Health) - Current diagnostic cutoffs for amnesiac mild cognitive impairment (aMCI) lead to underdiagnosis of women and overdiagnosis of men, according to new findings.

"Our results suggest that the application of sex-specific cut scores for defining verbal memory impairment improves diagnostic accuracy in both sexes and may result in earlier detection of memory impairment in women and avoid false diagnoses in men," Dr. Erin E. Sundermann of the University of California, San Diego, and colleagues with the Alzheimer's Disease Neuroimaging Initiative (ADNI) note in Neurology, online October 9.

In previous research, Dr. Sundermann and colleagues found that women with aMCI had better verbal memory than men with aMCI and a similar disease burden.

"These findings suggest that the female advantage in verbal memory may be a proxy for a verbal memory-specific increase in cognitive reserve that allows women to sustain what is considered normal verbal memory performance and delay aMCI diagnosis until more advanced disease states compared to men," they note.

The authors applied both sex-specific and typical cutoff scores on the Rey Auditory Verbal Learning Test to 453 women and 532 men from the ADNI.

Based on conventional criteria, 26% of women and 45% of men were classified as having aMCI. Using the sex-specific cutoffs, 36% of women and 35% of men would be considered to have aMCI.

Means and positivity rates for several Alzheimer's disease-associated markers for the "false negative" women and "false positive" men fell in between those of the true positive and true negative groups.

"If women with a considerable AD-related pathologic burden are inaccurately identified as cognitively normal, then pharmaceutical and cognitive interventions, as well as care, financial, and legal planning, are delayed," Dr. Sundermann and colleagues note. "Similarly, false diagnosis of aMCI in men without substantial AD-related pathology can lead to undue stress and decreased quality of life, as well as unneeded medications."

They conclude: "Replication of these results and additional longitudinal analyses are warranted in other aging cohort studies. If replicated, this work could have important implications for both clinical and research practices."


Neurology 2019.