Apolipoprotein epsilon4 allele and problems with orientation are associated with a persistent decline in cognition in community-dwelling elderly persons.
BACKGROUND
A decline in cognitive test scores in elderly persons can signal the beginning of a descent into dementia or may indicate only a short-term cognitive disturbance. It would be clinically useful to distinguish between the two outcomes and to identify characteristics of each.


METHODS
Four hundred thirty-seven community-dwelling elderly persons were given the Mini-Mental State Examination (MMSE) annually for an average of 7 years. A low score between baseline and final MMSE was identified. A low score 3 or more points lower than baseline score indicated cognitive decline. This decline was called persistent if the final MMSE score was also at least 3 points lower than baseline MMSE score; otherwise, the decline was considered transient.


RESULTS
Twenty participants (4.6%) experienced a persistent cognitive decline, 67 participants (15.3%) experienced a transient cognitive decline. Presence of the apolipoprotein epsilon4 allele was significantly associated with persistent cognitive decline (age-adjusted odd ratio [OR] = 11.46, p < .0001) but not with transient cognitive decline (age-adjusted OR = 1.53, p = .219). Incorrect answers on the orientation part of the MMSE at the time of cognitive decline was associated with persistent decline compared to transient decline (age-adjusted OR = 3.58, p = .058).


CONCLUSIONS
Persistent cognitive decline is an infrequent occurrence in community-dwelling elderly persons. Presence of the epsilon4 allele and errors made by the subject on questions of orientation may be useful in determining whether a cognitive decline is likely to be persistent.
Wayne
Sharon J
SJ
Aging and Genetic Epidemiology Program, Department of Internal Medicine, University of New Mexico School of Medicine, Albuquerque, NM 87131-5666, USA. swayne@salud.unm.edu
Vellas
Bruno J
BJ
Brodie
Steven G
SG
Garry
Philip J
PJ
Baumgartner
Richard N
RN
D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology; D000483:Alleles; D001057:Apolipoproteins E / Q000235:genetics / Q000378:metabolism*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000235:genetics; D015331:Cohort Studies; D016001:Confidence Intervals; D003221:Confusion / Q000175:diagnosis* / Q000235:genetics; D003704:Dementia / Q000175:diagnosis* / Q000235:genetics; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005819:Genetic Markers / Q000235:genetics; D015577:Geriatric Assessment; D006801:Humans; D008297:Male; D009516:New Mexico; D016017:Odds Ratio; D011336:Probability; D011446:Prospective Studies; D012111:Residence Characteristics; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
D001057:Apolipoproteins E; D005819:Genetic Markers