Stress at work in patients with cardiometabolic disease
Authors: Yulong Lian
Journal: The Lancet Diabetes & Endocrinology (2018)

Cardiometabolic disease is a common cause of mortality, disability, and health-care expenditure worldwide.1Kones R Rumana U Cardiometabolic diseases of civilization: history and maturation of an evolving global threat. An update and call to action.Ann Med. 2017; 49: 260-274Crossref PubMed Scopus (22) Google Scholar To date, the focus has been on the prevention and treatment of cardiometabolic disease via lifestyle and pharmacological interventions. However, given the increased prevalence of cardiometabolic diseases and their associated complications, new complementary targets for prevention and treatment are needed. In this context, there has been growing interest in the association between work stress and cardiometabolic disease. Many studies have linked work stress to increased risk of coronary heart disease, type 2 diabetes, stroke, and metabolic syndrome and showed that work stress might affect the development of cardiometabolic disease;2Kivimäki M Steptoe A Effects of stress on the development and progression of cardiovascular disease.Nat Rev Cardiol. 2018; 15: 215-229Crossref PubMed Scopus (411) Google Scholar, 3Lian Y Sun Q Guan S et al.Effect of changing work stressors and coping resources on the risk of type 2 diabetes: the OHSPIW cohort study.Diabetes Care. 2018; 41: 453-460Crossref PubMed Scopus (6) Google Scholar, 4Fransson EI Nyberg ST Heikkilä K et al.Job strain and the risk of stroke: an individual-participant data meta-analysis.Stroke. 2015; 46: 557-559Crossref PubMed Scopus (92) Google Scholar however, the association of work stress with cardiometabolic disease progression as an outcome has not been extensively investigated. In The Lancet Diabetes & Endocrinology, Mika Kivimäki and colleagues5Kivimäki M Pentti J Ferrie JE et al.Work stress and risk of death in adults with and without cardiometabolic disease: a multicohort study.Lancet Diabetes Endocrinol. 2018; (published online May 31.)http://dx.doi.org/10.1016/S2213-8587(18)30140-2PubMed Scopus (73) Google Scholar report their findings from a multicohort study to assess the effect of work stress (denoted as job strain or effort–reward imbalance) on risk of mortality, using data from the Individual-Participant Data Meta-analysis in Working Populations (IPD-Work) consortium. The investigators used psychosocial aspects of work to define work stress exposures on the basis of the two leading theoretical models: demand–control (job strain) and effort–reward imbalance. The demand–control model proposes that the combination of high psychological demands combined with little control of decision making leads to physiological strain. The effort–reward imbalance model posits that the lack of reciprocity between effort and reward at work could elicit stress reactions with adverse health outcomes. After a mean of 13·9 years of follow-up, job strain increased the risk of mortality in men with cardiometabolic disease, an association that remained even after adjustment for further conventional risk factors, treatment, and lifestyle factors, as well as statistical correction for multiple comparisons (hazard ratio 1·68, 95% CI 1·19–2·35). However, no significant effect was seen in women and individuals without cardiometabolic disease. Effort–reward imbalance was associated with an increased risk of mortality in men without cardiometabolic disease and decreased risk of mortality was in men with cardiometabolic disease, although the significance of this apparent protective effect was lost after Bonferroni correction for multiple testing. Additionally, the combination of both job strain and effort–reward imbalance was not associated with mortality in either men or women, with or without cardiometabolic disease. Despite the non-significance after Bonferroni correction, these results suggest that effort–reward imbalance might have a small protective effect on the risk for mortality of cardiometabolic disease in men, which is not in accordance with effort–reward imbalance theory. Although the authors argue that the difference in findings between the models might be related to different sources of stress and reduced effort in people with severe illness, other important prognostic factors associated with cardiometabolic disease might have biased these findings. The prevalence of poor mental health, such as psychological distress, clinical depression, and anxiety, is higher among patients with cardiometabolic disease than in the general population.6Arnold SV Smolderen KG Buchanan DM Spertus JA Perceived stress in myocardial infarction: long-term mortality and health status outcomes.J Am Coll Cardiol. 2012; 60: 1756-1763Crossref PubMed Scopus (106) Google Scholar Furthermore, compared with people with no stress, those with work stress tend to have a higher prevalence of poor mental health.7Laine H Saastamoinen P Lahti J Rahkonen O Lahelma E The associations between psychosocial working conditions and changes in common mental disorders: a follow-up study.BMC Public Health. 2014; 14: 588Crossref PubMed Scopus (23) Google Scholar These psychological distresses are likely to increase the mortality risk of patients with cardiovascular disease or diabetes.8Stewart RAH Colquhoun DM Marschner SL et al.Persistent psychological distress and mortality in patients with stable coronary artery disease.Heart. 2017; 103: 1860-1866Crossref PubMed Scopus (43) Google Scholar Other life and work stressors, such as social isolation, loneliness, workplace bullying, and job insecurity, might also contribute to the progression of cardiometabolic disease;2Kivimäki M Steptoe A Effects of stress on the development and progression of cardiovascular disease.Nat Rev Cardiol. 2018; 15: 215-229Crossref PubMed Scopus (411) Google Scholar, 9Elovainio M Hakulinen C Pulkki-Råback L et al.Contribution of risk factors to excess mortality in isolated and lonely individuals: an analysis of data from the UK Biobank cohort study.Lancet Public Health. 2017; 2: e260-e266Summary Full Text Full Text PDF PubMed Scopus (160) Google Scholar, 10László KD Engström K Hallqvist J Ahlbom A Janszky I Job insecurity and prognosis after myocardial infarction: the SHEEP Study.Int J Cardiol. 2013; 167: 2824-2830Summary Full Text Full Text PDF PubMed Scopus (14) Google Scholar however, these important prognostic factors for cardiometabolic disease were not considered in the IPD-Work study. Additionally, as Kivimäki and colleagues5Kivimäki M Pentti J Ferrie JE et al.Work stress and risk of death in adults with and without cardiometabolic disease: a multicohort study.Lancet Diabetes Endocrinol. 2018; (published online May 31.)http://dx.doi.org/10.1016/S2213-8587(18)30140-2PubMed Scopus (73) Google Scholar acknowledge in their discussion of the study's limitations, exposure misclassification due to the single baseline measure of work stress could have underestimated or overestimated associations. Nevertheless, their results are provocative and encourage careful attention to work stress reduction among patients with cardiometabolic diseases. Future approaches to strengthen the state of research on work stress and cardiometabolic mortality risk could include studies to clarify which mediators and moderators are most relevant in the association between work stress and the progression of cardiometabolic disease; longitudinal studies testing the association between the progression of cardiometabolic disease over time and a wide range of work stressors at the task, individual, social, and organisational level; and interventional studies aimed at decreasing work stress. There is accumulating evidence that the progression of cardiometabolic disease differs by sex, and the reason could be related to sex differences in traditional risk factors, such as cigarette smoking, or female-specific risk factors, such as pregnancy.11Humphries KH Izadnegahdar M Sedlak T et al.Sex differences in cardiovascular disease—impact on care and outcomes.Front Neuroendocrinol. 2017; 46: 46-70Crossref PubMed Scopus (135) Google Scholar Notably, a sex divergence in the effect of work stress on cardiometabolic mortality was also reported by Fransson and colleagues4Fransson EI Nyberg ST Heikkilä K et al.Job strain and the risk of stroke: an individual-participant data meta-analysis.Stroke. 2015; 46: 557-559Crossref PubMed Scopus (92) Google Scholar in a previous IPD-Work consortium analysis investigating job strain and the risk of stroke.5Kivimäki M Pentti J Ferrie JE et al.Work stress and risk of death in adults with and without cardiometabolic disease: a multicohort study.Lancet Diabetes Endocrinol. 2018; (published online May 31.)http://dx.doi.org/10.1016/S2213-8587(18)30140-2PubMed Scopus (73) Google Scholar The findings of Kivimäki and colleagues greatly expand the evidence for sex differences in cardiometabolic disease. Further research into the mechanisms responsible for the these differences in the effects of work stress would not only improve understanding of the prognosis of cardiometabolic disease, but also inform health policy makers and guideline committees about the need for sex-specific workplace interventions for the treatment and management of cardiometabolic disease. I declare no competing interests. Work stress and risk of death in men and women with and without cardiometabolic disease: a multicohort studyIn men with cardiometabolic disease, the contribution of job strain to risk of death was clinically significant and independent of conventional risk factors and their treatment, and measured lifestyle factors. Standard care targeting conventional risk factors is therefore unlikely to mitigate the mortality risk associated with job strain in this population. Full-Text PDF Open Access