Nurses working rotating night shifts may face unintended health consequences, according to a study published in The Journal of the American Medical Association.
Researchers, led by Céline Vetter, Ph.D., Channing Division of Network Medicine, Department of Medicine, of Brigham and Women's Hospital in Boston, reviewed data from the Nurses' Health Study and found that nurses working these shifts for 10 years or more had at least a 15 percent increased risk of coronary heart disease, compared to those who avoided night shifts.
The study also suggested that the increased risk was independent of the studied nurses' personal diet and exercise habits.
"There are a number of known risk factors for coronary heart disease, such as smoking, poor diet, lack of physical activity and elevated body mass index," Vetter told NBC News. "However, even after controlling for these risk factors, we still saw an increased risk of coronary heart disease associated with rotating shift work."
The team also found other risks associated with working frequent night shifts. The more night shifts the studied women worked, on average the more weight they gained. These nurses were also more likely to be married to men with less education than those who work daytime shifts, were more likely to be smokers, were less likely to be mothers and used more painkillers, according to the study.
"Given that shift work may affect both sleep and social support, further research in populations with more extensive information on sleep duration, quality, and timing as well as work hours seems warranted," the team concluded.
A March 2015 study, which also analyzed data from the Nurses' Health Study, found that nurses working rotating night shifts also faced an 11 percent higher risk of all causes of death. A study later that year also found that nurses who do not have enough time to rest between shifts may also face serious health risks.
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