RALEIGH, N.C. (WNCN) – Daylight Saving Time will begin on March 13 and all of us seem to take a few days to recover after “springing forward” in March.
Sluggishness, sleepiness and a feeling of jet lag are quite common. Now, a new study has just shown that DST change is associated with a brief but significant increased risk for stroke.
Daylight Saving Time was created during World War I in order to help curb energy use. Daylight Saving Time can impact our circadian rhythms (our sleep/wake cycle) and can impact how much melatonin (sleep hormone) we produce. We produce sleep hormone when we are exposed to darkness and it is essential that we produce melatonin in our brains in order to help regulate sleep/wake cycles. The change in time can throw this system “out of whack” and can produce a jet lag-like syndrome—like we moved over one time zone for a period of months. In addition, changes in the time can affect other hormones in the body such as cortisol—which can also contribute to the feelings of jet lag.
The problems with DST are the worst in the spring, when we spring forward and all lose one hour of sleep. The sun rises later, making it more difficult to wake in the morning because we reset our natural clocks using the light. When these cues change (as in the case of the night we spring forward) it causes big confusion.
Any time your sleep is shortened or disrupted due to DST changes we often see decreases in performance, concentration and memory, as well as fatigue and daytime sleepiness.
In addition, during the first week of DST (in March) there’s a spike in heart attacks, according to multiple studies over the last several years. It is likely that this link exists due the fact that losing an hour of sleep increases stress and provides less time to recover overnight. Work accidents and motor vehicle accidents seem to increase during the time change as well.
New research, carried out at the University of Turku in Finland, has uncovered a rather surprising association. The team found that changing the clock forward or back by an hour increases the risk of stroke.
In the research study, a decade of Finnish health care records for thousands of patients were reviewed. Nearly 3,033 individuals who were hospitalized during the week after a daylight saving time transition were reviewed for incidence of stroke. These patients were and compared it with the rate of stroke in a group of 11,801 people who were hospitalized two weeks before or two weeks after the clock change. In the study, the researchers found that there was an eight percent increase in stroke in the two days after the change to DST. After two days the rate of stroke returned to normal levels. Individuals over the age of 65 were 20 percent more likely to have a stroke immediately after the shift as were those with cancer.
While there are some existing theories that might help explain why the change to DST might bring about such a negative outcome, at this point we just don’t know. Some prior research has shown that stroke rates are associated with our circadian rhythms—it may be that the change in time is so disruptive that it predisposes us to stroke.
However, this is the first time that daylight saving has been specifically investigated as a risk factor.
So, how can we cope?
As a rule of thumb it takes at least one day for each hour of time change
Here are some tips to ease transition:
- Expose yourself to as much bright light as possible during the waking hours and avoid bright lights at night.
- Eliminate caffeine or alcohol within two hours of bed
- Go to sleep and get up at the same time every day
- Consider melatonin supplements
To get in touch with Dr. Campbell, you can head to his website.