Poor Physical Function in Later Life Correlates with Increased Mortality
There are no great surprises to be found in the research materials here, which report on the correlation between increasing frailty and mortality in later life. Those people who struggle the most with physical activities tend to be those most likely to die. It is interesting to compare this with research on smaller cohorts that demonstrates the ability of structured exercise programs to improve physical capabilities and reduce mortality in later life. While some fraction of frailty is connected to the deeper processes of aging, a sizable degree of the problem emerges as the result of a lack of physical activity in older people. The choice to live a sedentary lifestyle has consequences.
It is well known that motor function, also commonly known as physical function or physical capability, declines with age, but rates of decline differ widely from person to person. And while studies show that decline in cognitive (mental) skills can emerge up to 15 years before death, it's not clear whether the same is true for physical abilities. To explore this further, researchers examined several measures of motor function for their associations with mortality over a 10 year period from around age 65.
Their findings are based on over 6,000 participants of the Whitehall II Study, which recruited participants aged 35-55 years in 1985-88 to look at the impact of social, behavioural, and biological factors on long term health. Between 2007 and 2016, participants underwent motor function assessments on up to three occasions. These included measures of walking speed, chair rise time, and grip strength, along with self-reported measures of functioning and difficulties with activities of daily living, such as dressing, using the toilet, cooking and grocery shopping.
After taking account of other potentially influential factors, the researchers found that poorer motor function was associated with an increased mortality risk of 22% for walking speed, 15% for grip strength, and 14% for timed chair rises, while difficulties with activities of daily living were associated with a 30% increased risk. These associations became progressively stronger with later life assessments.