The study published in the Journal Occupational Medicine found that every year working shifts can increase the risk by 1% and that shift workers are 13% more likely to develop ischaemic heart disease than daytime workers.
Researchers studied the records of more than 320,000 participants with 19,782 cases of ischaemic heart disease.
Ischaemic heart disease also known as coronary artery disease is the leading cause of death in many parts of the world.
According to the study, the exact reason shift workers are developing ischaemic heart disease is not known for certain but it is felt that disruption of the normal sleep-wake cycle, the increased stress involved in shift work and unhealthy lifestyles often associated with shift work, could be contributing.
“This is the largest study about shift work and ischemic heart disease ever undertaken,” said study author, Professor Chen.
“The number of deaths due to ischaemic heart disease has continued to rise with 7.6 million deaths in 2005 and 8.9 million people dying due to the condition in 2015. Patients can require surgical interventions and medications meaning ischaemic heart disease is one of the biggest burdens on health care systems.
“This study summarised previous studies and drew a positive conclusion that shift work contributes to the incidence of ischaemic heart disease. The longer an employee spends working shifts, the higher their risk of developing ischaemic heart disease,” added Professor Chen.
“Shift work is a timesaving work system, it can earn more profit but it can also cause harm to the health of employees, so employers should reduce shift work as much as possible.
“Employers should pay attention to staff members who are experiencing symptoms of heart problems as well as those with a family history of heart disease. Employers could provide health promotion, such as information on how to prevent and deal with ischaemic heart disease. Companies could also consider providing health checks to detect early signs of heart problems.”
