Working 'rotating night shifts' can pose serious threats to health, longevity

A new study has recently revealed that working rotating night shifts can pose serious threats to people's health and longevity.

An international team of researchers investigated possible links between rotating night shift work and all-cause, CVD, and cancer mortality in a study of almost 75,000 registered U.S. nurses.

Using data from the Nurses' Health Study (NHS), the authors analyzed 22 years of follow-up and found that working rotating night shifts for more than five years was associated with an increase in all-cause and CVD mortality.

Mortality from all causes appeared to be 11 percent higher for women with 6-14 or 15 years of rotating night shift work. CVD mortality appeared to be 19 percent and 23 percent higher for those groups, respectively.

There was no association between rotating shift work and any cancer mortality, except for lung cancer in those who worked shift work for 15 or more years (25 percent higher risk.)

According to Eva S. Schernhammer, MD, DrPH, currently Associate Professor of Medicine, Harvard Medical School, and Associate Epidemiologist, Department of Medicine, Brigham and Women's Hospital, Boston, this study was one of the largest prospective cohort studies worldwide with a high proportion of rotating night shift workers and long follow-up time.

A single occupation (nursing) provides more internal validity than a range of different occupational groups, where the association between shift work and disease outcomes could be confounded by occupational differences, she further added.