STAYING active has long been touted by health experts as a way to maintain both a healthy body and mind.
But new research suggests that people working jobs that require high levels of physical activity could be at greater risk of dementia and cognitive impairment.
Occupations that require a lot of physical activity are carers and nursing assistants, the study authors said[/caption]
Around 900,000 Brits are currently thought to be living with dementia.
The study by the Norwegian National Centre of Ageing and Health, Columbia Mailman School of Public Health and the Butler Columbia Aging Center found that people toiling at physically exhausting jobs for long periods of time could be at greater risk of the brain robbing disease.
Authors gave the example of physically demanding jobs highlighted in the study, including:
- salespeople – retail and other
- nursing assistants
- care assistants
- crop farmers
- animal producers
“Consistently working in an occupation with intermediate or high occupational physical activity was linked to an increased risk of cognitive impairment, indicating the importance of developing strategies for individuals in physically demanding occupations to prevent cognitive impairment,” the study authors wrote.
They classed physically demanding jobs as ones that “require considerable use of your arms and legs and moving your whole body, such as climbing, lifting, balancing, walking, stooping, and handling of materials”.
It follows research suggesting that spending more than 10 hours a day sitting down “rapidly” increases your risk of dementia.
Using one of the world’s largest population-based studies of dementia – the HUNT4 70+ Study – researchers examined how occupational physical activity between the ages of 33–65 was linked to a risk of developing dementia and mild cognitive impairment after the age of 70.
They analysed the data of 7,005 participants, 902 of which were diagnosed with dementia later in life.
Another 2,407 were diagnosed with mild cognitive impairment.
The team found that people doing physically demanding work had a 15.5 per cent higher risk of having dementia or being cognitively impaired.
But the risk fell to 9 per cent for those doing jobs with low physical demands.
Researchers noted that mild cognitive impairment diagnosis isn’t necessarily followed by dementia.
They said there were “several plausible explanations” for why people in physically exhausting jobs might have a higher risk of the devastating brain disease.
“Higher occupational physical demands in later adulthood have previously been linked to smaller hippocampal volume and poorer memory performance,” researchers said.
“Similarly, individuals working in physically hazardous jobs or with high job demands – psychological or physical – combined with low job control have been found to perform poorer on cognitive tests in later age.”
Study authors said this may suggest that high occupational physical demands have a ‘detrimental effect’ on brain health and cognitive function in older ages, raising the risk of impairment later in life.
Lack of time to recuperate and recover from these greater physical demands could also lead to ‘wear and tear’ of both the body and brain, they argued.
Occupations such as nursing or sales are “often characterised by a lack of autonomy, prolonged standing, hard work, rigid working hours, stress, a higher risk of burnout, and sometimes […] inconvenient working days,” they added.
Meanwhile, jobs with low physical demands might also give workers more flexible working hours and more time for breaks and recovery.
And many jobs that don’t require bursts of physical activity, such as as engineering, administration, and teaching may also be “more cognitively stimulating, which could contribute to more favourable cognitive development throughout the course of a person’s life”, the study authors said.
Lead author Vegard Skirbekk, a professor of Population and Family Health at Columbia Public Health, said: “Our work also highlights what is called the physical activity paradox – the association of leisure time physical activity with better cognitive outcomes, and how work related physical activity can lead to worse cognitive outcomes.”
He observed that the pre-clinical period of dementia may start up to two decades prior to symptom onset.
“Our results particularly underscore the need to follow up on individuals with high lifetime occupational, physical activity as they appear to have a greater risk of developing dementia,” Dr Skirbekk noted.
“Future research should assess how occupational physical activity and interventions to reduce occupational physical activity or technological changes leading to altered activity, in combination with other characteristics of the job, relate to dementia and mild cognitive impairment risk in older ages.
“This will further our understanding of the association between occupational histories and cognitive impairment.”
Source of data and images: thesun