Physically demanding jobs and heart risk
Consistent results from two studies say demanding physical work is associated with an increased risk of coronary heart disease
17th April 2013 - If you have a physically demanding job and think a good work out in your leisure time is good for your heart you may need to think again.
Two European studies, presented at this year's EuroPRevent cardiology congress in Rome, suggest that demanding physical work has a detrimental effect on a person's risk of coronary heart disease.
It's not certain why but the study authors believe it may be down to stress or overloading the cardiovascular system.
The first study evaluated the jobs of 250 patients with a first stroke, 250 with a first acute coronary event and 500 equally matched controls.
Those suffering the stroke and coronary events were more commonly engaged in physically demanding occupations than the controls. After adjusting for various potential confounding factors such as age, family history of cardiovascular disease and adherence to the Mediterranean diet, the results confirmed that those in less physically demanding jobs were associated with a 20% lower likelihood of acute coronary events.
Dr Demosthenes Panagiotakos, from Harokopio University, Athens says people with physically demanding manual jobs should be considered a primary target group for prevention of cardiovascular disease because of their higher risk.
Dr Panagiotakos says the results could possibly be attributed to the stress experienced by people with physically demanding jobs. He believes stress may be one reason why hard physical work may not be comparable to the physical exercise recommended for health and well-being, which tends to take place in leisure time and to, consequently, be non-stressful.
In addition, he says hard physical work is often not well paid, which may restrict access to the healthcare system.
The second study from investigators in Belgium and Denmark, also supports the view that physically demanding work is a risk factor for coronary heart disease, even when leisure-time activity is taken into account.
This was a cohort study of more than 14,000 middle-aged men who were free of coronary disease at the outset of the study in 1994-1998. Standardised questionnaires were used to assess job strain and the level of physical activity at work and during leisure time. Again, adjustments were made for things like age, smoking and alcohol consumption.
Results showed an overall beneficial effect of leisure time physical activity, but an adverse effect of demanding physical work. An "interaction effect" was also evident in the results. So, while moderate-to-high physical activity during leisure time was associated with a 60% reduced risk of coronary events in men with jobs with low physical activity, this protective effect was not observed in those workers who were exposed to high physical work demands.
After adjusting for socio-demographic and well established coronary risk factors, men with high physical job demands were more than four times likely to have coronary heart disease when they also engaged in physical activity during leisure time.