This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
Abstract
Objective To examine whether the use of sex-specific norms and cut scores to identify memory impairment improves diagnostic accuracy of amnestic mild cognitive impairment (aMCI) compared to non–sex-specific (typical) norms/cut scores given the female advantage in verbal memory.
Methods We calculated sex-specific and typical norms/cut scores (age and education specific) for impairment on the Rey Auditory Verbal Learning Test in the Mayo Clinic Study of Aging. Norms/cut scores were applied to 453 women and 532 men from the Alzheimer's Disease Neuroimaging Initiative. We compared sex differences in rates of aMCI (Jak/Bondi criteria) for sex-specific vs typical norms/cut scores. Using sex-specific cut scores as the true condition and typical cut scores as the predicted condition, we categorized participants as true positives (TPs), false positives (FPs), true negative (TNs), or false negative (FNs). In cross-sectional analyses within sex, we compared positivity rates of CSF hyperphosphorylated tau/β-amyloid (Aβ) and cortical Aβ deposition ([18F]AV45 PET) and APOE ε4 frequency among diagnostic comparison groups.
Results The frequency of aMCI was higher in men when using typical norms/cut scores. Using sex-adjusted norms/cut scores led to the identification of 10% FNs (missed aMCI cases) among women and 10% FPs among men. Biomarker analyses supported the hypothesis that sex-specific diagnostic criteria improves diagnostic accuracy. Biomarkers rates were higher in FNs vs TNs and similar in FNs and TPs. Biomarker rates were lower in FPs vs TPs and similar between FPs and TNs.
Conclusion Results suggest that non–sex-specific aMCI diagnostic criteria led to a 20% diagnostic error rate. Accounting for sex differences in verbal memory performance may improve aMCI classification.
Glossary
- Aβ=
- β-amyloid;
- AD=
- Alzheimer disease;
- ADNI=
- Alzheimer's Disease Neuroimaging Initiative;
- aMCI=
- amnestic mild cognitive impairment;
- ANCOVA=
- analysis of covariance;
- CDR-SOB=
- Clinical Dementia Rating Sum of Boxes;
- CI=
- confidence interval;
- FN=
- false negative;
- FP=
- false positive;
- NC=
- normal control;
- OR=
- odds ratio;
- p-tau=
- hyperphosphorylated tau;
- RAVLT=
- Rey Auditory Verbal Learning Test.;
- SUVR=
- standardized uptake value ratio;
- TN=
- true negative;
- TP=
- true positive
Footnotes
Go to Neurology.org/N for full disclosures. Funding information and disclosures deemed relevant by the authors, if any, are provided at the end of the article.
↵* These authors contributed equally to this work.
Data used in preparation of this article were obtained from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database (adni.loni.usc.edu). As such, the investigators within the ADNI contributed to the design and implementation of ADNI and/or provided data but did not participate in analysis or writing of this report. A complete listing of ADNI investigators can be found in Supplemental Data File and at: links.lww.com/WNL/A992.
CME Course: NPub.org/cmelist
- Received November 21, 2018.
- Accepted in final form June 5, 2019.
- © 2019 American Academy of Neurology
AAN Members: Sign in with your AAN member credentials (e-mail or 6-digit Member ID number)
Non-AAN Member subscribers: Sign in with subscriber credentials
Log in using your username and password
Purchase access
Disputes & Debates: Rapid online correspondence
NOTE: All authors' disclosures must be entered and current in our database before comments can be posted. Enter and update disclosures at http://submit.neurology.org. Exception: replies to comments concerning an article you originally authored do not require updated disclosures.
- Stay timely. Submit only on articles published within the last 8 weeks.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- 200 words maximum.
- 5 references maximum. Reference 1 must be the article on which you are commenting.
- 5 authors maximum. Exception: replies can include all original authors of the article.
- Submitted comments are subject to editing and editor review prior to posting.