Night shifts interfere with sleep

Working the night shift interferes with sleep, particularly for workers in their 30s and 40s, but the problem may be reversible, says a study.

Sleep problems don’t appear to get worse over time perhaps because young workers who have a lot of trouble with sleep issues are more likely to quit shift work, according to Philip Tucker of Britain’s Swansea University who led the study.

Using a large employment database, researchers looked at the relationship between shift work and sleep problems in workers of different ages and over time.

As in previous studies, shift workers had a higher rate of sleep problems than day workers. Shift work was specifically related to waking up too early rather than other types of sleep problems.

The effects were most apparent in the early to middle years of working life - that is workers in their 30s and 40s. Former shift workers had more sleep problems than those who had never done shift work.

However, more years of shift work did not lead to greater sleep problems. Instead, workers who gave up shift work seemed to be a “self-selected” group who tended to have more problems with shift work.

Sleep problems thus seem to be a “reversible consequence” of shift work although it may take a while after giving up shift work before sleep returns to normal.

The study confirms the previously reported link between shift work and sleep problems, while lending new insights into the course of those problems over time, says a release of the Journal of Occupational and Environmental Medicine.