A report presented at a recent meeting of the American Academy of Neurology, summarized by The Daily Telegraph, suggests turning the clock back or forward an hour affects the circadian rhythm in individuals and this puts some people at an increased risk of ischemic stroke. Stoke is a risk factor with many older people. Ischemic stroke is triggered by blockage of a blood vessel supplying the brain. It is the most common type of stroke, accounting for almost nine out of every 10 cases.
Daylight Saving Time was introduced by William Willett in 1907. The idea was to maximize use of the daytime and prevent wasting it first thing in the morning during the summer.
New research from the University of Turku in Finland has looked at the effect of alterations to the body clock increasing the chance of a stroke. To do this, the research team, led by Dr. Jori Ruuskanen, examined 10 years of data to assess the stroke rate in Finland.
This data, Bioscience Technology reports, was then compared with the rate of stroke in a group of people hospitalized during the week after daylight savings time (which totaled some 3,033 patients) with the rate of stroke relating to people who were hospitalized 14 days before or after that week (some 11,801 people).
By subjecting the data to statistical analysis, it was found there was an 8 percent increase in the overall rate of ischemic stroke for the first two days following the implementation of daylight saving time. Once two days had passed, there was no significant difference.
While the risk was evident, certain groups of people were found to be more vulnerable than others. This included those aged over 65 years, and people suffering from cancer. With older people, the risk rose from 8 percent to 20 percent, for example.
It should be noted the researchers found that the risk does not apply to all people and it is only temporary. The research findings require further study and they have yet to be reported to a peer-reviewed journal.