Fabrice Coffrini / AFP via Getty Images
- Working 55 hours or more a week was linked to 745,000 deaths from strokes and heart disease in 2016, a WHO report said.
- More than 70% of people who died were men, middle-aged and older, and from South East Asia or Western Pacific regions.
- The COVID-19 pandemic is accelerating the trend towards working longer hours, the WHO said.
- See more stories on Insider's business page.
Long working hours contributed to 745,000 deaths globally in 2016, a 29% increase since 2000, according to a joint study by the World Health Organization (WHO) and International Labour Organization.
The study found that working 55 hours or more a week was linked to a 35% increase in the risk of stroke and 17% higher risk of deadly heart disease, compared to working a 35 to 40-hour week.
Researchers took data from more than 2,300 surveys conducted between 1970 to 2018 to estimate the proportion of people exposed to long working hours in different countries, and combined this with meta analyses showing the relative risk of developing heart disease and stroke.
The total number of deaths attributable to longer working hours were then calculated using the WHO Global Health Estimates data, which recorded causes of death among the global population between 2000 and 2016.
Deaths related to longer working hours usually occurred later in life, sometimes decades after people had retired, researchers said.
Nearly three quarters of people who died were men who were middle-aged and older. People living in Southeast Asia and the Western Pacific, a region that includes China, Japan and Australia, were the most at risk of dying from heart disease and stroke associated with working long hours, researchers said.
The WHO said that 9% of the world work long hours, and that the COVID-19 pandemic was "accelerating developments" towards longer working hours.
"Teleworking has become the norm in many industries, often blurring the boundaries between home and work," Dr. Tedros Adhanom Ghebreyesus, the WHO director-general, said in a statement. "In addition, many businesses have been forced to scale back or shut down operations to save money, and people who are still on the payroll end up working longer hours."