Depression and anxiety symptoms are associated with cerebral FDDNP-PET binding in middle-aged and older nondemented adults.
OBJECTIVE
Amyloid senile plaques and tau neurofibrillary tangles are neuropathologic hallmarks of Alzheimer disease, which may be associated with mild cognitive impairment (MCI) or mood and anxiety symptoms years before the dementia diagnosis. To address this issue, the authors obtained positron emission tomography (PET) scans after intravenous injections of 2-(1-{6-[(2-[fluorine-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile (FDDNP), a molecule that binds to amyloid plaques and neurofibrillary tangles, to determine whether symptoms of depression and anxiety in nondemented subjects were associated with increased FDDNP-PET binding values.


METHODS
Forty-three middle-aged and elderly volunteers received clinical and FDDNP-PET assessments. Subjects were nondemented--23 of them were diagnosed with MCI and 20 were cognitively normal. Subjects with a diagnosis of major depression or an anxiety disorder were excluded. Correlations between standardized measures of depressive and anxiety symptoms and regional FDDNP binding values were calculated.


RESULTS
The MCI and comparison subjects did not differ by the depression and anxiety scores. In the MCI group, depression scores correlated with lateral temporal and trait anxiety scores correlated with posterior cingulate FDDNP binding. In the comparison group, depression scores correlated with medial temporal, and trait anxiety scores correlated with medial temporal and frontal FDDNP binding.


CONCLUSIONS
This is the first report to demonstrate a relationship between the severity of depression and anxiety symptoms and FDDNP binding values in nondemented middle age and older individuals. The results suggest a relationship between relatively mild mood symptoms and biomarkers of cerebral amyloid and tau deposition and vary according to degree of cognitive impairment. The presence of MCI may signify different pathophysiological mechanisms underlying mood and anxiety symptoms.
Lavretsky
Helen
H
Department of Psychiatry and Biobehavioral Sciences and Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, CA 90095-9668, USA. hlavretsky@mednet.ucla.edu
Siddarth
Prabha
P
Kepe
Vladimir
V
Ercoli
Linda M
LM
Miller
Karen J
KJ
Burggren
Alison C
AC
Bookheimer
Susan Y
SY
Huang
Sung-Cheng
SC
Barrio
Jorge R
JR
Small
Gary W
GW
D000368:Aged; D000369:Aged, 80 and over; D000682:Amyloid; D001007:Anxiety / Q000000981:diagnostic imaging* / Q000503:physiopathology; D001921:Brain / Q000000981:diagnostic imaging*; D002540:Cerebral Cortex; D003072:Cognition Disorders / Q000000981:diagnostic imaging; D003863:Depression / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D016874:Neurofibrillary Tangles / Q000000981:diagnostic imaging*; D009570:Nitriles; D058225:Plaque, Amyloid / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography
C444520:2-(1-(6-((2-fluoroethyl)(methyl)amino)-2-naphthyl)ethylidene)malononitrile; D000682:Amyloid; D009570:Nitriles