TY - JOUR
T1 - Baseline Microglial Activation Correlates With Brain Amyloidosis and Longitudinal Cognitive Decline in Alzheimer Disease
AU - Wang, Qing
AU - Chen, Gengsheng
AU - Schindler, Suzanne E.
AU - Christensen, Jon
AU - McKay, Nicole S.
AU - Lu, Esther
AU - Wang, Sicheng
AU - Sun, Zhexian
AU - Hassenstab, Jason
AU - Su, Yi
AU - Flores, Shaney
AU - Hornbeck, Russ
AU - Cash, Lisa
AU - Cruchaga, Carlos
AU - Fagan, Anne M.
AU - Tu, Zhude
AU - Morris, John C.
AU - Mintun, Mark A.
AU - Wang, Yong
AU - Benzinger, Tammie L.S.
N1 - Publisher Copyright:
© American Academy of Neurology.
PY - 2022/5/8
Y1 - 2022/5/8
N2 - Background and ObjectivesThis study aims to quantify microglial activation in individuals with Alzheimer disease (AD) using the 18-kDa translocator protein (TSPO) PET imaging in the hippocampus and precuneus, the 2 AD-vulnerable regions, and to evaluate the association of baseline neuroinflammation with amyloidosis, tau, and longitudinal cognitive decline.MethodsTwenty-four participants from the Knight Alzheimer Disease Research Center (Knight ADRC) were enrolled and classified into stable cognitively normal, progressor, and symptomatic AD groups based on clinical dementia rating (CDR) at 2 or more clinical assessments. The baseline TSPO radiotracer [11C]PK11195 was used to image microglial activation. Baseline CSF concentrations of Aβ42, Aβ42/Aβ40 ratio, tau phosphorylated at position 181 (p-tau181), and total tau (t-tau) were measured. Clinical and cognitive decline were examined with longitudinal CDR and cognitive composite scores (Global and Knight ADRC-Preclinical Alzheimer Cognitive Composite [Knight ADRC-PACC] Score).ResultsParticipants in the progressor and symptomatic AD groups had significantly elevated [11C]PK11195 standard uptake value ratios (SUVRs) in the hippocampus but not in the precuneus region. In the subcohort with CSF biomarkers (16 of the 24), significant negative correlations between CSF Aβ42 or Aβ42/Aβ40 and [11C]PK11195 SUVR were observed in the hippocampus and precuneus. No correlations were observed between [11C]PK11195 SUVR and CSF p-tau181 or t-tau at baseline in those regions. Higher baseline [11C]PK11195 SUVR averaged in the whole cortical regions predicted longitudinal decline on cognitive tests.DiscussionMicroglial activation is increased in individuals with brain amyloidosis and predicts worsening cognition in AD.Classification of EvidenceThis study provides Class II evidence that in patients with AD, higher baseline [11C]PK11195 SUVR averaged in the whole cortical regions was associated with longitudinal decline on cognitive tests.
AB - Background and ObjectivesThis study aims to quantify microglial activation in individuals with Alzheimer disease (AD) using the 18-kDa translocator protein (TSPO) PET imaging in the hippocampus and precuneus, the 2 AD-vulnerable regions, and to evaluate the association of baseline neuroinflammation with amyloidosis, tau, and longitudinal cognitive decline.MethodsTwenty-four participants from the Knight Alzheimer Disease Research Center (Knight ADRC) were enrolled and classified into stable cognitively normal, progressor, and symptomatic AD groups based on clinical dementia rating (CDR) at 2 or more clinical assessments. The baseline TSPO radiotracer [11C]PK11195 was used to image microglial activation. Baseline CSF concentrations of Aβ42, Aβ42/Aβ40 ratio, tau phosphorylated at position 181 (p-tau181), and total tau (t-tau) were measured. Clinical and cognitive decline were examined with longitudinal CDR and cognitive composite scores (Global and Knight ADRC-Preclinical Alzheimer Cognitive Composite [Knight ADRC-PACC] Score).ResultsParticipants in the progressor and symptomatic AD groups had significantly elevated [11C]PK11195 standard uptake value ratios (SUVRs) in the hippocampus but not in the precuneus region. In the subcohort with CSF biomarkers (16 of the 24), significant negative correlations between CSF Aβ42 or Aβ42/Aβ40 and [11C]PK11195 SUVR were observed in the hippocampus and precuneus. No correlations were observed between [11C]PK11195 SUVR and CSF p-tau181 or t-tau at baseline in those regions. Higher baseline [11C]PK11195 SUVR averaged in the whole cortical regions predicted longitudinal decline on cognitive tests.DiscussionMicroglial activation is increased in individuals with brain amyloidosis and predicts worsening cognition in AD.Classification of EvidenceThis study provides Class II evidence that in patients with AD, higher baseline [11C]PK11195 SUVR averaged in the whole cortical regions was associated with longitudinal decline on cognitive tests.
UR - http://www.scopus.com/inward/record.url?scp=85126076391&partnerID=8YFLogxK
U2 - 10.1212/NXI.0000000000001152
DO - 10.1212/NXI.0000000000001152
M3 - Article
C2 - 35260470
AN - SCOPUS:85126076391
SN - 2332-7812
VL - 9
JO - Neurology: Neuroimmunology and NeuroInflammation
JF - Neurology: Neuroimmunology and NeuroInflammation
IS - 3
M1 - e1152
ER -