Study explores connection between shift work, severe strokes

College Station, TX – The lack of a consistent eating and sleeping schedule may disrupt the circadian rhythms of shift workers and make them more likely to suffer a severe stroke, according to a recent study from Texas A&M University.

Researchers studied the performance of rats placed on simulated fixed schedules and shift schedules. For the shift-schedule group, activity time and lights-off time varied from day to day. That group experienced ischemic strokes that were more severe – both in terms of brain damage and the loss of sensation and limb movement – than the group whose schedule aligned with circadian rhythms.

“The body is synchronized to night and day by circadian rhythms – 24-hour cycles controlled by internal biological clocks that tell our bodies when to sleep, when to eat and when to perform numerous physiological processes,” David Earnest, a professor in the Department of Neuroscience and Experimental Therapeutics at the College of Medicine, said in a press release. “A person on a shift work schedule, especially on rotating shifts, challenges, or confuses, their internal body clocks by having irregular sleep-wake patterns or meal times.”

The researchers called for additional research into the relationship between circadian clocks and brain chemistry.

The study was published online June 2 in the journal Endocrinology.