CONTEXT: Impairment of episodic memory is an early and defining feature of Alzheimer disease (AD). The apolipoprotein E (APOE) epsilon 4 allele is known to influence risk of AD but it has been difficult to establish whether it affects episodic memory differently from other cognitive functions. OBJECTIVE: To examine the association of epsilon 4 with decline in different cognitive systems. DESIGN: Longitudinal cohort study. SETTING: More than 40 groups of Catholic clergy from across the United States. PARTICIPANTS: Older Catholic clergy members without clinical evidence of dementia at baseline underwent annual clinical evaluations for up to 6 years. Of 624 persons eligible for follow-up, 611 (98%) participated, of whom 161 (26%) had at least 1 epsilon 4 allele. They completed an average of 5.5 evaluations (range, 2-7). MAIN OUTCOME MEASURES: Incident AD and annual rates of change in episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability. RESULTS: The presence of epsilon 4 was associated with risk of developing AD on follow-up (relative risk, 1.92; 95% confidence interval, 1.27-2.89). In a series of random effects models, epsilon 4 was associated with impaired baseline function in episodic memory and visuospatial ability and with more rapid decline in all domains. The effect of epsilon 4 on annual decline in episodic memory (>3-fold increase) was significantly stronger than its effect on decline in other cognitive systems (P<.01), and at baseline, its effect on episodic memory was marginally stronger than its effect on other cognitive domains (P =.06). CONCLUSION: The results suggest that the APOE epsilon 4 allele influences risk of AD by a relatively selective effect on episodic memory.
CONTEXT: Impairment of episodic memory is an early and defining feature of Alzheimer disease (AD). The apolipoprotein E (APOE) epsilon 4 allele is known to influence risk of AD but it has been difficult to establish whether it affects episodic memory differently from other cognitive functions. OBJECTIVE: To examine the association of epsilon 4 with decline in different cognitive systems. DESIGN: Longitudinal cohort study. SETTING: More than 40 groups of Catholic clergy from across the United States. PARTICIPANTS: Older Catholic clergy members without clinical evidence of dementia at baseline underwent annual clinical evaluations for up to 6 years. Of 624 persons eligible for follow-up, 611 (98%) participated, of whom 161 (26%) had at least 1 epsilon 4 allele. They completed an average of 5.5 evaluations (range, 2-7). MAIN OUTCOME MEASURES: Incident AD and annual rates of change in episodic memory, semantic memory, working memory, perceptual speed, and visuospatial ability. RESULTS: The presence of epsilon 4 was associated with risk of developing AD on follow-up (relative risk, 1.92; 95% confidence interval, 1.27-2.89). In a series of random effects models, epsilon 4 was associated with impaired baseline function in episodic memory and visuospatial ability and with more rapid decline in all domains. The effect of epsilon 4 on annual decline in episodic memory (>3-fold increase) was significantly stronger than its effect on decline in other cognitive systems (P<.01), and at baseline, its effect on episodic memory was marginally stronger than its effect on other cognitive domains (P =.06). CONCLUSION: The results suggest that the APOE epsilon 4 allele influences risk of AD by a relatively selective effect on episodic memory.
Authors: May A Beydoun; Adel Boueiz; Marwan S Abougergi; Melissa H Kitner-Triolo; Hind A Beydoun; Susan M Resnick; Richard O'Brien; Alan B Zonderman Journal: Neurobiol Aging Date: 2010-07-08 Impact factor: 4.673
Authors: Aron S Buchman; Patricia A Boyle; Robert S Wilson; Todd L Beck; Jeremiah F Kelly; David A Bennett Journal: Alzheimer Dis Assoc Disord Date: 2009 Jan-Mar Impact factor: 2.703
Authors: Kristin R Krueger; Robert S Wilson; David A Bennett; Neelum T Aggarwal Journal: Alzheimer Dis Assoc Disord Date: 2009 Oct-Dec Impact factor: 2.703
Authors: Patricia A Boyle; Aron S Buchman; Robert S Wilson; Jeremiah F Kelly; David A Bennett Journal: Neuroepidemiology Date: 2009-11-11 Impact factor: 3.282
Authors: Kathleen M Hayden; Peter P Zandi; Nancy A West; Joann T Tschanz; Maria C Norton; Chris Corcoran; John C S Breitner; Kathleen A Welsh-Bohmer Journal: Arch Neurol Date: 2009-11