Grant: Operating Grant

Recent national reports raise concern about the growing risk of heart disease in younger and middle-aged adults. The face of heart disease is changing such that young adults are entering adulthood with a number of cardiovascular disease (CVD) risk factors and older adults have lived longer with their unhealthy habits and are developing heart disease at an earlier age. A recent Heart and Stroke Foundation report identified adult women as a population at risk. Given that adults spend a significant amount of time in the workplace, the potential influence of the work environment on CVD risk requires careful examination. In this study we are focusing on one aspect of the work environment (shift work) and an identified at risk population (adult females) as approximately 28% of employed women have worked at some time in a shift work pattern, and this proportion of female shift workers is the highest among hospital workers. Current studies, predominantly completed among male workers, suggest that individuals working night shift may be at increased CVD risk; however, the mechanisms linking shift work and CVD risk are unclear. The purpose of this study is to empirically test a mechanistic model that postulates that shift work is associated with increased CVD risk through its influences on 3 different but interactive physiological, behavioural and social pathways. We will conduct an observational study and recruit 300 female hospital employees who have been in the workforce for at least 10 years. Information will be obtained through clinical assessment, biochemical measures, continuous actigraphy and self-report. Our analysis plan is designed to elucidate the different hypothesized pathways linking shift work to CVD risk in working women. The findings from this study will contribute novel findings to our understanding of the harmful and protective characteristics of shift work, and will inform the development of healthy workplace policies.