Electrocardiographic Changes and Work-related Stress – a Cross- sectional Study in a General Working Population Master thesis in Medicine

..................................................................................................................................... 3 Background ................................................................................................................................ 5 Job strain and effort-reward imbalance .................................................................................. 5 Associations with the risk of cardiovascular disease ............................................................. 8 Work-related stress and electrocardiographic changes ........................................................ 12 Aims ......................................................................................................................................... 16 Scientific issue .......................................................................................................................... 16 Methods .................................................................................................................................... 16 Population and data collection ............................................................................................. 16 Variables ............................................................................................................................... 17 Electrocardiography ......................................................................................................... 17 Psychosocial work variables ............................................................................................ 18 Smoking ........................................................................................................................... 20 Statistical methods ................................................................................................................ 20 Power calculations .................................................................................................................... 21 Ethics ........................................................................................................................................ 22 Results ...................................................................................................................................... 23 Discussion ................................................................................................................................ 25 Methodological limitations .................................................................................................. 25 Design ............................................................................................................................... 25 Power ................................................................................................................................ 26 Measurements ................................................................................................................... 26 Analyses ........................................................................................................................... 28 Methodological strengths ..................................................................................................... 29 Resting heart rate and job strain ........................................................................................... 30 QTc ....................................................................................................................................... 31 Suggestions for future studies .............................................................................................. 33 Conclusions .............................................................................................................................. 34 Populärvetenskaplig sammanfattning ...................................................................................... 36 Acknowledgements .................................................................................................................. 38 References ................................................................................................................................ 38 Tables and appendices .............................................................................................................. 42 Questionnaire for job strain .................................................................................................. 46 Questionnaire for effort-reward............................................................................................ 47