A simple workplace intervention can reduce the impact of stress on the heart, researchers reported in Hypertension: Journal of the American Heart Association.
Office workers who faced layoffs -- a significant stress-inducer -- were able to achieve small, but significant changes in heart rate variability and a small decrease in arterial blood pressure by participating in a stress management program at work.
After participating in the year-long stress management program, workers' scores on a test that measures perceived stress were significantly lower than baseline scores. Moreover, workers said they felt less tired than they did before the stress management training.
"And we were able to achieve these results in a working environment, without impinging on productivity, and with zero cost to the company," said Massimo Pagani, M.D., senior author of the study and professor of medicine at the University of Milan in Italy.
Job-related stress is one of several factors that may increase the risk of heart attack. So by addressing stress "at work, where stress occurs, rather than in a clinic, we may be able to prevent these workers from becoming patients," Pagani said.
Researchers recruited 91 office workers at a DuPont subsidiary in Italy which was downsizing its workforce by 10 percent. The average age of the volunteers was 40 years of age, 59 were men, who were, on average, normal weight with a body mass index (BMI) of 24 kg/m2. All of the volunteers said they were experiencing work-related stress.
The stressed workers were compared to a control group of 79 healthy volunteers, who worked outside of the company and reported no work-related stress. The average age of controls was 38, 52 were men, and the average BMI was 23 kg/m2.
Workers and controls underwent baseline assessment by a clinical psychologist and completed self-administered questionnaires which assessed overall stress, tiredness perception and bodily stress-related symptoms.
Researchers also tested the autonomic nervous system (ANS), which is a regulatory component of the nervous system which controls our internal organs, including heart rate and blood vessels to help us adapt to changes in the environment. Importantly, the ANS adjusts and modifies the internal bodily functions in response to stress.
Researchers evaluated the ANS by using a single lead electrocardiogram (ECG). This is a scaled down version of the usual multiple lead ECG, which is a common clinical test used to determine if the heart rate and rhythm are normal or if heart damage has occurred. Subjects were first monitored while lying down and then again while standing. Researchers recorded blood pressure while the subjects were in both positions.
At baseline, the workers had significantly higher stress and tiredness scores than controls, averaging 5.20 versus 2.94 for stress and 5.28 versus 3.27 for tiredness. Workers also reported more stress-related symptoms such as difficult sleep, pounding of the heart or gastrointestinal problems.
Compared with controls, the stressed workers had altered values in an ECG measurement which assessed the low frequency component of the "RR interval variability," which assesses nervous system regulation of heart rate. So, as expected, workers facing layoffs were feeling more stress and their heart rhythm was showing signs of that stress.
"This is typical of the stressed individual -- they are facing psychological pressure, but they don't want to hear about psychologists because they are feeling real, clinical symptoms," Pagani said.
After baseline assessment, the workers were offered the opportunity to participate in weekly, one-hour stress management sessions during lunch breaks or in a passive program that offered articles and monthly e-mails on stress reduction techniques.
Participants in the passive program also had access to services offered by the company's medical department. The weekly stress management sessions focused on mental relaxation techniques, as well as cognitive restructuring exercises and coping skills to face life stressors -- including work-related stress.
Twenty-six of the 91 stressed employees signed up for the stress management sessions and 25 signed up for the passive stress management program.
At baseline, the autonomic measures (ECG and arterial pressure) were similar in both intervention groups, but after a year "the stress management program induced a significant, small reduction in arterial pressure, and clear changes in ECG derived stress indices.
"Our study provides a potential model for the assessment of work-related stress at an individual level and suggests that stress management programs can be implemented at the worksite," Pagani said. "These programs can reduce stress symptom levels, revert stress-related ANS dysregulation, and lower resting arterial pressure.
"The practical long-term impact of this approach on symptoms, well-being and health of interested workers requires further specific longitudinal studies on large populations."