Stress and unhealthy lifestyle increase risk of heart disease
13 May 2013
People with job stress and an unhealthy lifestyle are at higher risk of coronary artery disease than people who have job stress but lead healthy lifestyles, according to work published in CMAJ (Canadian Medical Association Journal) by researchers from UCL's Department of Epidemiology and Public Health.
To determine whether a healthy lifestyle can help reduce the effects of job stress on coronary artery disease the researchers looked at seven cohort studies from a large European initiative that included 102,128 people who were disease-free during the 15-year study period (1985–2000). Participants, ranging in age from 17–70 (mean 44.3) years came from the United Kingdom, France, Belgium, Sweden and Finland. More than half (52%) were women.
Of the total participants, 15,986 (16%) reported job stress, which was determined from specific job-related questions in the studies. The investigators defined three lifestyle categories based on smoking, alcohol consumption, physical activity/inactivity and obesity (body mass index).
The risk of coronary artery disease was highest among participants who reported job strain and an unhealthy lifestyle. Those with job strain and a healthy lifestyle had about half the rate of this disease.
Professor Mika Kivimäki, UCL Epidemiology and Public Health
A "healthy lifestyle" had no lifestyle risk factors, "moderately unhealthy lifestyle" had one risk factor and "unhealthy lifestyle" included 2–4 lifestyle risk factors.
A total of 1,086 participants had coronary artery disease events during the follow-up period.
The 10-year incidence of coronary artery disease was 18.4 per 1,000 people for people with job strain and 14.7 per 1,000 for those without job strain.
People with an unhealthy lifestyle had a significantly higher 10-year incidence rate (30.6 per 1,000) compared to those with a healthy lifestyle (12.0 per 1,000). The incidence rate was 31.2 per 1,000 for participants with job strain and an unhealthy lifestyle but only 14.7 per 1,000 for those with job strain and a healthy lifestyle.
"The risk of coronary artery disease was highest among participants who reported job strain and an unhealthy lifestyle," writes Professor Mika Kivimäki, UCL Epidemiology and Public Health. "Those with job strain and a healthy lifestyle had about half the rate of this disease.
"These observational data suggest that a healthy lifestyle could substantially reduce the risk of coronary artery disease risk among people with job strain."
Evidence from randomised controlled trials has shown that lifestyle changes such as weight loss and stopping smoking can reduce the risk of disease.
"In addition to stress counselling, clinicians might consider paying closer attention to lifestyle risk factors in patients who report job strain," the authors conclude.
Image caption: A stressball, from Yurri on Flickr
Media contact: David Weston