A new study conducted by researchers from the Texas A & M Health Science Centre College of Medicine says that shift work can put workers out of sync with their body clocks, leading to more severe strokes. The study was supported by the American Heart Association. It was published in the journal Endocrinology.
Say the researchers, The body is synchronised to night and day by circadian rhythms and 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. It`s not the longer hours or the weird hours necessarily that is the problem. Instead, it is the change in the timing of waking, sleeping and eating every few days that unwinds our body clocks and makes it difficult for them to maintain their natural, 24-hour cycle.
The research has shown that shift work can lead to more severe ischemic strokes. These strokes are the leading cause of disability in the United States. They occur when blood flow is cut off to part of the brain.
The team used an animal model for the study. They found that the subjects that were on shift work schedules had more severe stroke outcomes, in terms of both brain damage and loss of sensation and limb movement than controls on regular 24-hour cycles of day and night.
The study also showed that males and females show major differences in the degree to which the stroke was exacerbated by circadian rhythm disruption; in males, the gravity of stroke outcomes in response to shift work schedules was much worse than in females.
Say the researchers, These sex differences might be related to reproductive hormones. Young women are less likely to suffer strokes, as compared with men of a similar age, and when they do, the stroke outcomes are likely to be less severe. In females, estrogen is thought to be responsible for this greater degree of neuroprotection.