Working night shifts could impair memory by up to 79 per cent in middle-aged and older adults, according to a new study. The research, conducted by a team from York University in Canada, analyzed data from 47,811 adults and found that those who worked night shifts had significantly higher rates of cognitive impairment compared to those who only worked during the day.
The study revealed that individuals currently working night shifts had a 79 per cent higher risk of cognitive impairment, while those who had previously worked night shifts during their longest job had a 53 per cent higher risk. These findings suggest that disruption to the circadian rhythm, or our body clock, may be to blame. The authors of the study speculate that the disruptive circadian stimuli from night shift work could contribute to neurodegeneration and cognitive impairment.
Russell Foster, a professor of circadian neuroscience at the University of Oxford, underscored the importance of these findings. He noted that the results align with both laboratory-based and field studies, which have shown that sleep and circadian rhythm disruption are linked to poorer health outcomes, including impaired emotional and cognitive responses.
The negative effects of shift work on health have been well-documented. Prior research has connected night shift work to irregular and fast heartbeat, as well as an increased risk of atrial fibrillation and coronary heart disease. In the UK, the number of night shift workers has decreased in recent years, with 8.7 million individuals working night shifts in 2022 compared to 9.5 million in 2016.
These findings serve as a reminder of the potential risks associated with night shift work, particularly for middle-aged and older adults. Employers may need to consider implementing strategies to mitigate the negative effects of night shifts on workers’ health and cognitive function.