The Professional Geriatric Care Manager’s Blog

Cognitive Activities Delay Onset of Memory Decline in Persons Who Develop Dementia

This summary is from MedScape Nursing and the author is Laurie Barkley MD

cHall CB, Lipton RB, Sliwinski M, Katz MJ, Derby CA, Verghese J
Neurology. 2009;73:356-361

Summary

People who ultimately develop dementia first have a more rapid rate of decline in memory as well as other cognitive functions. Educational attainment in early life and participation in activities that stimulate cognitive function later in life are thought to improve cognitive reserve, thereby delaying the onset of memory decline before dementia is clinically apparent.

In the Bronx Aging Study, 488 community-residing individuals with no cognitive impairment at baseline underwent epidemiologic, clinical, and cognitive evaluations every 12 to 18 months, and 101 of these individuals developed incident dementia. A change point model determined the effect of self-reported participation in cognitively stimulating leisure activities on the onset of accelerated memory decline in these 101 individuals, as measured by the Buschke Selective Reminding Test.

For each additional self-reported day of cognitive activity at baseline, the onset of accelerated memory decline was delayed by 0.18 years. After that onset, however, memory decline was more rapid in persons with higher levels of cognitive activity at baseline. Beyond the effect of cognitive activities, adding educational attainment to the model did not significantly improve the fit.

Viewpoint

Findings from this large, prospective cohort study show that cognitive activities in late life improve cognitive reserve independently of educational level. One explanation could be that the effect on cognitive reserve of educational attainment early in life may be mediated by cognitive activity in later life. Another explanation could be that early life education may be a determinant of cognitive reserve, and that better educated individuals may choose to participate in cognitively stimulating activities without affecting reserve.

Limitations of this study include reliance on self-reporting regarding leisure activities and restriction to one geographical area (Bronx, New York), limiting generalizability of the findings to other geographic locations and ethnic composition. Randomized clinical trials could help determine whether increasing participation in cognitive activities is effective in preventing or delaying dementia.