TY - JOUR
T1 - Aβ amyloid, cognition, and APOE genotype in healthy older adults
AU - Lim, Yen Ying
AU - Ellis, Kathryn A.
AU - Ames, David
AU - Darby, David
AU - Harrington, Karra
AU - Martins, Ralph N.
AU - Masters, Colin L.
AU - Rowe, Christopher
AU - Savage, Greg
AU - Szoeke, Cassandra
AU - Villemagne, Victor L.
AU - Maruff, Paul
AU - The AIBL Research Group
PY - 2013/9
Y1 - 2013/9
N2 - Background: Only one study has investigated the relationship between cerebral β-amyloid (Aβ), apolipoprotein E (APOE) ε4 genotype, and cognition. Although significant relationships between cerebral Aβ and cognition were observed in ε4 carriers but not noncarriers, the magnitude of this relationship was not reported. Further, when demographic variables were controlled, the influence of APOE ε4 on the relationship between cerebral Aβ and cognition dissipated. Methods: In 144 healthy older adults who had undergone amyloid scanning and APOE ε4 genotyping in the Australian Imaging, Biomarkers, and Lifestyle (AIBL) Flagship Study of Ageing, correlations were conducted to determine the magnitude of relationship between cerebral Aβ and cognition in ε4 carriers and noncarriers. Fisher's Z was used to compare these correlations and Cohen's q determined the magnitude of difference between correlations. Results: Cerebral Aβ was significantly associated with tasks of visual and verbal episodic memory in APOE ε4 carriers. This association was not observed in ε4 noncarriers. The relationship between cerebral Aβ and episodic memory in ε4 carriers was significantly different from that in ε4 noncarriers, and the magnitude of this difference was small to moderate. Conclusions: In APOE ε4 carriers, there is a moderate negative relationship between cerebral Aβ and episodic memory. This suggests that increased cerebral Aβ may signify the onset of preclinical AD, especially in healthy older adults who are genetically at risk for AD.
AB - Background: Only one study has investigated the relationship between cerebral β-amyloid (Aβ), apolipoprotein E (APOE) ε4 genotype, and cognition. Although significant relationships between cerebral Aβ and cognition were observed in ε4 carriers but not noncarriers, the magnitude of this relationship was not reported. Further, when demographic variables were controlled, the influence of APOE ε4 on the relationship between cerebral Aβ and cognition dissipated. Methods: In 144 healthy older adults who had undergone amyloid scanning and APOE ε4 genotyping in the Australian Imaging, Biomarkers, and Lifestyle (AIBL) Flagship Study of Ageing, correlations were conducted to determine the magnitude of relationship between cerebral Aβ and cognition in ε4 carriers and noncarriers. Fisher's Z was used to compare these correlations and Cohen's q determined the magnitude of difference between correlations. Results: Cerebral Aβ was significantly associated with tasks of visual and verbal episodic memory in APOE ε4 carriers. This association was not observed in ε4 noncarriers. The relationship between cerebral Aβ and episodic memory in ε4 carriers was significantly different from that in ε4 noncarriers, and the magnitude of this difference was small to moderate. Conclusions: In APOE ε4 carriers, there is a moderate negative relationship between cerebral Aβ and episodic memory. This suggests that increased cerebral Aβ may signify the onset of preclinical AD, especially in healthy older adults who are genetically at risk for AD.
KW - Cerebral Ab burden
KW - APOE 34
KW - episodic memory
KW - healthy older adults
KW - AIBL
UR - http://www.scopus.com/inward/record.url?scp=84883557408&partnerID=8YFLogxK
U2 - 10.1016/j.jalz.2012.07.004
DO - 10.1016/j.jalz.2012.07.004
M3 - Article
C2 - 23159043
AN - SCOPUS:84883557408
VL - 9
SP - 538
EP - 545
JO - Alzheimer's and Dementia
JF - Alzheimer's and Dementia
SN - 1552-5260
IS - 5
ER -