Three-year changes in cognitive performance as a function of apolipoprotein E genotype: evidence from very old adults without dementia.

This study examined whether baseline cognitive performance and 3-year longitudinal changes were influenced by apolipoprotein E epsilon 4 (APOE-epsilon 4) allele. Participants consisted of 20 APOE-epsilon 4 (2 epsilon 2/epsilon 4; 17 epsilon 3/epsilon 4; 1 epsilon 4/epsilon 4) and 54 non-epsilon 4 (12 epsilon 2/epsilon 3; 42 epsilon 3/epsilon 3) very old adults without dementia (M = 81.82 +/- 5.06 years) participating in a population-based longitudinal study. Cognitive performance was indexed by the Mini-Mental State Examination and multiple indexes of memory, visuospatial, and verbal performance. The results indicated no significant baseline differences between the 2 APOE groups in any cognitive performance measure. However, analyses revealed that the APOE-epsilon 4 group experienced greater negative change in recognition memory for faces and words. Changes in tasks assessing other abilities did not vary as a function of APOE status. The authors concluded that APOE-epsilon 4 status may not influence cognitive performance in adults without dementia and speculated that when such effects do occur (e.g., decline in recognition memory), these may be related to impending dementia, rather than to the influence of the specific genotype on cognition in normal aging.