We read with interest the study by Kivimaki and colleagues,1 which examines the longitudinal relationship between job strain and health behaviours on coronary heart disease. Their findings support previous Canadian research2 that suggests psychosocial working conditions play an important role in the etiology of chronic health conditions. We were, however, surprised by the authors’ conclusion that suggests that when a patient’s job strain and lifestyle factors contribute to heart disease, clinicians should tell those patients to simply adopt a healthier lifestyle.1
That low socioeconomic position is associated with both lower job control and poorer health behaviours is well established.3 That individualistic approaches to improving health behaviours do not improve — and can exacerbate — social inequalities in health is also well established.4 Although we agree with Kivimaki and colleagues1 that changing the psychosocial work environment is challenging, it is possible with concerted efforts from management and employees.5 In addition, although primary prevention programs, such as physical activity, continue to have limited success at the population level, these programs still seem to be at the forefront of many approaches to improve the health of the population. Telling a patient who experiences a high level of job strain to lose weight is likely as effective as telling a patient who is overweight to find a better job, which based on this study, would confer some decreased risk.
We also question using obesity as a lifestyle factor. People don’t start or stop being obese like they start smoking, drinking or being inactive. Obesity would be better conceptualized as a mediating factor between both health behaviours and job strain, and cardiovascular disease. This grouping would allow a more realistic estimate of the risks associated with lifestyle factors, noting that apart from smoking, the hazard ratios associated with job strain were similar to those of alcohol and physical inactivity.1
Work is an increasingly important part of the lives of many Canadians. Real progress on reducing the incidence of chronic diseases such cardiovascular disease and obesity are likely to be made by better understanding the relationships between health behaviours and working conditions (including job strain) rather than treating them as separate approaches to primary prevention.