Monday, April 23, 2018

Handgrip Strength May Offer Clues About Cognitive Function in People With Mood Disorders


Handgrip strength may provide a useful indicator of cognitive impairment in people with major depression and bipolar disorder, according to a study in JAMA Psychiatry

Joseph Firth, Ph.D., of the University of Western Sydney and colleagues found that greater grip strength in individuals with major depression and bipolar disorder was associated with better performance on measures of reasoning, reaction time, and memory.

Firth and colleagues analyzed data from the UK Biobank—a nationwide, health-oriented, cohort study conducted across the United Kingdom. The final analysis included 110,067 people who had their handgrip strength evaluated (each participant received a single, maximum score indicating the greatest strength for each hand). The participants also performed a variety of cognitive functioning tasks on a computer (these tasks evaluated visuospatial memory, reaction time, reasoning, prospective memory, and numeric memory).

Of the group, 85,893 participants had no indication of any mood disorders, 22,699 reported recurrent major depression, and 1,475 reported bipolar disorder (type I or type II). The mean age of the healthy control, bipolar disorder, and major depression samples was 53.7 years, 54.4 years, and 55.5 years, respectively.

In participants with major depression and no indication of any mood disorders, greater handgrip strength was a significant predictor of better cognitive performance in all five domains: visual memory, reaction time, reasoning, number memory, and prospective memory. In people with bipolar disorder, greater handgrip strength was significantly associated with visual memory, reaction time, reasoning, and prospective memory. 

“To our knowledge, this study is the first to identify handgrip strength as a marker of cognitive function in mood disorders,” Firth and colleagues wrote. “However, the cross-sectional design of this investigation means that further longitudinal and mechanistic research must be conducted to determine the causative nature of the association between handgrip strength and cognition in psychiatric populations.”

Noting that strength training exercise interventions have been shown to improve cognitive functioning in aging populations, the authors suggested that improving muscular fitness may be a “therapeutic target” for individuals with mood disorders. 

“Future research should investigate causality, assess the functional implications of handgrip strength in psychiatric populations, and examine how interventions to improve muscular fitness affect neurocognitive status and socio-occupational functioning,” they concluded.   

For related information, see the Psychiatric News article “Minimal Exercise May Help Prevent Future Depression.”

(Image: iStock/Steve Debenport)