11C-PiB imaging of human immunodeficiency virus-associated neurocognitive disorder.
OBJECTIVE
To evaluate whether the amyloid-binding agent carbon 11-labeled Pittsburgh Compound B ((11)C-PiB) could differentiate Alzheimer disease (AD) from human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND) in middle-aged HIV-positive participants.


METHODS
(11)C-PiB scanning, clinical assessment, and cerebrospinal fluid (CSF) analysis were performed. Both χ(2) and t tests assessed differences in clinical and demographic variables between HIV-positive participants and community-living individuals observed at the Knight Alzheimer's Disease Research Center (ADRC). Analysis of variance assessed for regional differences in amyloid-β protein 1-42 (Aβ42) using (11)C-PiB.


METHODS
An ADRC and HIV clinic.


METHODS
Sixteen HIV-positive participants (11 cognitively normal and 5 with HAND) and 19 ADRC participants (8 cognitively normal and 11 with symptomatic AD).


METHODS
Mean and regional (11)C-PiB binding potentials.


RESULTS
Participants with symptomatic AD were older (P < .001), had lower CSF Aβ42 levels (P < .001), and had higher CSF tau levels (P < .001) than other groups. Regardless of degree of impairment, HIV-positive participants did not have increased (11)C-PiB levels. Mean and regional binding potentials were elevated for symptomatic AD participants (P < .001).


CONCLUSIONS
Middle-aged HIV-positive participants, even with HAND, do not exhibit increased (11)C-PiB levels, whereas symptomatic AD individuals have increased fibrillar Aβ42 deposition in cortical and subcortical regions. Observed dissimilarities between HAND and AD may reflect differences in Aβ42 metabolism. (11)C-PiB may provide a diagnostic biomarker for distinguishing symptomatic AD from HAND in middle-aged HIV-positive participants. Future cross-sectional and longitudinal studies are required to assess the utility of (11)C-PiB in older individuals with HAND.
Department of Neurology, Washington University in St. Louis, Campus Box 8111, 660 S Euclid Ave, St Louis, MO 63110, USA. bances@wustl.edu
Beau M
BM
Ances
Tammie L
TL
Benzinger
Jon J
JJ
Christensen
Jewell
J
Thomas
Rohit
R
Venkat
Mengesha
M
Teshome
Patricia
P
Aldea
Anne M
AM
Fagan
David M
DM
Holtzman
John C
JC
Morris
David B
DB
Clifford
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging / Q000235:genetics; D016229:Amyloid beta-Peptides / Q000134:cerebrospinal fluid; D000814:Aniline Compounds; D001057:Apolipoproteins E / Q000235:genetics; D052160:Benzothiazoles; D016022:Case-Control Studies; D002540:Cerebral Cortex / Q000000981:diagnostic imaging / Q000473:pathology; D003072:Cognition Disorders / Q000134:cerebrospinal fluid / Q000000981:diagnostic imaging* / Q000209:etiology* / Q000235:genetics; D005260:Female; D015658:HIV Infections / Q000134:cerebrospinal fluid / Q000150:complications*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000134:cerebrospinal fluid; D049268:Positron-Emission Tomography; D013844:Thiazoles
C475519:2-(4'-(methylamino)phenyl)-6-hydroxybenzothiazole; D016229:Amyloid beta-Peptides; D000814:Aniline Compounds; D001057:Apolipoproteins E; D052160:Benzothiazoles; D010446:Peptide Fragments; D013844:Thiazoles; C075222:amyloid beta-protein (1-42)