Study examines frailty among female shift workers

Toronto — Middle-aged and older shift workers are more likely to be considered frail – particularly women who work rotating shifts, a recent study out of Canada suggests.

A team led by researchers from York University used data for nearly 48,000 participants between the ages of 45 and 85 in the Canadian Longitudinal Study on Aging and followed up after three years to measure for frailty. Frailty was defined as a person’s likelihood toward disease and death. 

The researchers looked at 52 factors that likely shorten lifespan, including depression, osteoarthritis, history of heart attacks and mobility issues. Participants who had at least five of the factors were considered “mildly frail,” while those with at least 11 were considered “very frail.”

Overall, around 20% of the participants were involved in shift work. This group had a higher likelihood of frailty compared with those who worked only daytime hours. Additionally, more than a quarter of the shift workers were found to be mildly frail, and 7% were very frail. Women whose “longest job consisted of rotating shift work” were especially likely to be considered frail, as more than 31% were deemed mildly frail and nearly 11% fell into the very frail category.

Shift work can disrupt the body’s circadian rhythms, which can contribute to numerous health issues, according to a York press release. “We cannot ignore the negative health outcomes related to shift work, including cardiovascular diseases, diabetes, stroke and certain cancers,” said study co-author Durdana Khan, a doctoral student at the university.

Khan added that as more women work outside of a normal 9-to-5 schedule, focusing on exercise and nutrition can lessen the negative effects of shift work.

The study, which builds on previous research conducted by Khan and her colleagues suggesting that shift work may be linked to delayed menopause, was published online in the Journal of Occupational and Environmental Medicine.