Physical Performance Is Associated with Working Memory in Older People with Mild to Severe Cognitive Impairment
BACKGROUND
Physical performances and cognition are positively related in cognitively healthy people. The aim of this study was to examine whether physical performances are related to specific cognitive functioning in older people with mild to severe cognitive impairment.


METHODS
This cross-sectional study included 134 people with a mild to severe cognitive impairment (mean age 82 years). Multiple linear regression was performed, after controlling for covariates and the level of global cognition, with the performances on mobility, strength, aerobic fitness, and balance as predictors and working memory and episodic memory as dependent variables.


RESULTS
The full models explain 49-57% of the variance in working memory and 40-43% of episodic memory. Strength, aerobic fitness, and balance are significantly associated with working memory, explaining 3-7% of its variance, irrespective of the severity of the cognitive impairment. Physical performance is not related to episodic memory in older people with mild to severe cognitive impairment.


CONCLUSIONS
Physical performance is associated with working memory in older people with cognitive impairment. Future studies should investigate whether physical exercise for increased physical performance can improve cognitive functioning. This trial is registered with ClinicalTrials.gov NTR1482.