Bidirectional association between executive and physical functions among older adults: A systematic review

We aimed to examine the bidirectional associations between specific executive function (EF) and physical function (PF) subdomains among older adults.

A systematic literature search (MEDLINE, EMBASE, PsycINFO, EBSCOHOST, Scopus and EmCare) was undertaken from February 2018 to May 2020. Observational studies measuring associations between EF and PF subdomains among older adults were included.

Twenty-nine studies met the inclusion criteria. Twenty-seven studies reported associations between EF and PF. There were bidirectional associations between slower processing speed and slower gait speed; slower processing speed and lower muscle strength; and lower verbal fluency and slower gait speed. Lower muscle strength was unilaterally associated with lower working memory.

We found consistent bidirectional associations between processing speed with gait speed and muscle strength, and verbal fluency and gait speed. There was a unidirectional association between muscle strength and working memory. Common causal mechanisms for EF and PF require further studies.