Format

Send to

Choose Destination
Neurology. 2014 Oct 28;83(18):1613-9. doi: 10.1212/WNL.0000000000000939. Epub 2014 Sep 26.

Unrecognized preclinical Alzheimer disease confounds rs-fcMRI studies of normal aging.

Author information

1
From the Program in Neuroscience, Division of Biological and Biomedical Science (M.R.B.), and Departments of Neurology (J.B.T., A.Z.S., L.W., A.M.F., J.C.M., B.M.A.) and Radiology (A.Z.S., T.B., B.M.A.), School of Medicine, Washington University in St. Louis; and Hope Center for Neurological Disorders (A.M.F., T.B., B.M.A.), Knight Alzheimer's Disease Research Center (A.M.F., T.B., J.C.M., B.M.A.), and Department of Biomedical Engineering (B.M.A.), Washington University in St. Louis, MO. brierm@wusm.wustl.edu.
2
From the Program in Neuroscience, Division of Biological and Biomedical Science (M.R.B.), and Departments of Neurology (J.B.T., A.Z.S., L.W., A.M.F., J.C.M., B.M.A.) and Radiology (A.Z.S., T.B., B.M.A.), School of Medicine, Washington University in St. Louis; and Hope Center for Neurological Disorders (A.M.F., T.B., B.M.A.), Knight Alzheimer's Disease Research Center (A.M.F., T.B., J.C.M., B.M.A.), and Department of Biomedical Engineering (B.M.A.), Washington University in St. Louis, MO.

Abstract

OBJECTIVE:

To determine whether, and to what degree, preclinical Alzheimer disease (AD) confounds studies of healthy aging where "healthy" is based on cognitive normality alone.

METHODS:

We examined the effects of preclinical AD in cognitively normal older individuals using resting-state functional connectivity MRI. We investigated 2 groups of cognitively normal participants: one group with evidence of preclinical AD as assessed by CSF markers of AD and the other group with normal CSF biomarkers.

RESULTS:

There were significant interactions between age and biomarker status in the default-mode, dorsal attention, and salience resting-state networks. In the group with evidence of preclinical AD, there were dramatic changes in functional connectivity with age. In the group without evidence of preclinical AD, those changes were greatly attenuated. In most regions with significant interactions of age and biomarker status, the age-related change in functional connectivity in the normal biomarker group was indistinguishable from zero.

CONCLUSIONS:

These results suggest that preclinical AD accounts for a substantial portion of the reported effects of aging in the extant functional connectivity literature.

PMID:
25261500
PMCID:
PMC4223085
DOI:
10.1212/WNL.0000000000000939
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center