Relationship Between Work Stress And Cardiovascular Disease In Middle-aged And Elderly Populations In Europe

ObjectivesTo study the association between physical job strain,psychosocial job strain,job reward and the occurrence of cardiovascular disease（CVD）in the main job of middle-aged and older employees aged 50+,and to explore the mediating effects of self-rated health in the physical and psychosocial job strain-CVD association.MethodsThis study used data from The Survey of Health,Ageing,and Retirement in Europe（SHARE）.In total 5,651 participants from wave1 aged 50-88 years were follow-up for 12 years to detect incident CVD.The level of job strain in the main job of the participants was assessed by work stress scale of the job demand-control model（JDC）and effort-reward imbalance（ERI）model,including four dimensions of physical job demands,psychosocial job demands,job control and job reward.Dichotomized physical job demands were crossed with the dichotomized job control to obtain a four-category variable,physical job strain,which was coded as low physical strain（low physical job demands+high job control）,passive physical job（low physical job demands+low job control）,active physical job（high physical job demands+high job control）and high physical strain（high physical job demands+low job control）.Similarly,the dichotomized psychosocial job demands were crossed with the dichotomized job control to obtain a four-category variable,psychosocial job strain,which was coded as low psychosocial strain,passive psychosocial job,active psychosocial job and high psychosocial strain.Four categories of physical strain and job reward were then combined into an 8-category variable,physical job strain-job reward according to their crosstabulation:low strain-high reward（low physical strain+high reward）,low strain-low reward（low physical strain+low reward）,passive job-high reward（passive physical job+high reward）,passive job-low reward（passive physical job+low reward）,active job-high reward（active physical job+high reward）,active job-low reward（active physical job+low reward）,high strain-high reward（high physical strain+high reward）,high strain-low reward（high physical strain+low reward）.CVD was ascertained from self-report physician diagnosis and included stroke,myocardial infarction,coronary thrombosis,or any other cardiac problem.After adjusting for covariates including age,gender,education,BMI,hypertension,hyperlipidemia,diabetes,smoking,alcohol drinking and physical activity,Cox regression models were used to investigate the association between work stress and CVD,respectively.The mediating effect of self-rated health on the association between physical job strain,psychological job strain and CVD was investigated using structural equation modeling.Results1.Over 12 years follow-up,a total of 574（10.16%）individuals developed CVD.Taking low physical job demands,high job control and high job reward as reference respectively,high physical job demands（HR=1.29,95%CI=1.06-1.58）,low job control（HR=1.19,95%CI=1.00-1.42）and low job reward（HR=1.22,95%CI=1.02-1.46）were significantly and positively related to the risk of CVD after adjusting for covariates.In4-category of physical job strain,compare to low physical strain,passive physical job（HR=1.23,95%CI=1.01-1.50）,active physical job（HR=1.41,95%CI=1.05-1.90）and high physical strain（HR=1.47,95%CI=1.12-1.93）were at increased risk of CVD.The results of stratified analysis showed that among the female participants,compared to low physical strain,both passive physical job（HR=1.45,95%CI=1.02-2.08）and active physical job（HR=2.16,95%CI=1.31-3.57）were positively associated with an increased risk of CVD.Among low level education participants,compared with those with low physical strain,participants with active physical job（HR=2.03,95%CI=1.21-3.40）and high physical strain（HR=1.89,95%CI=1.19-2.99）was associated with increased risk of CVD.Among high level education participants,compared with those with low physical strain,participants with passive physical job（HR=1.41,95%CI=1.02-1.95）was associated with increased risk of CVD.Among smoking participants,compared with those with low physical strain,participants with high physical strain（HR=1.84,95%CI=1.12-3.01）was associated with increased risk of CVD.No link between physical job strain and CVD was found in men,moderate education and non-smokers.2.Compared to participants with low strain-high reward,those with passive job-low reward（HR=1.49,95%CI=1.15-1.94）,active job-high reward（HR=1.48,95%CI=1.05-2.08）,high strain-high reward（HR=1.49,95%CI=1.05-2.12）and high strain-low reward（HR=1.55,95%CI=1.07-2.26）were at increased risk of CVD.3.In the mediating analysis,taking low physical strain as a reference,there was a significant mediating effect of self-rated health in passive physical job-CVD association(β_a1=0.063,β_b=0.065,β_a1*β_b=0.004),active physical job-CVD association(β_a2=0.047,β_b=0.065,β_a2*β_b=0.003)and high physical strain-CVD association(β_a3=0.100,β_b=0.065,β_a3*β_b=0.007).And the effect size of the mediating effect was14.3%,9.1%and 17.1%,respectively,that is,self-rated health may explain 14.3%of the association between passive physical job and CVD,9.1%between active physical job and CVD,and 17.1%between high physical strain and CVD.Conclusions1.In the relationship between work stress and CVD,physical job strain and job reward may be the key factors to increase the risk of CVD,especially among women,those with low or high education,and smokers.2.Compared to the relationship between physical job strain and CVD,the combination of physical job strain and job reward did not significantly increase the risk of CVD.3.Self-rated health may play a mediating effect in the relationship between physical strain and CVD.