People who already are at risk for stroke may face an increased risk after the switch to daylight saving time — at least temporarily, a new study shows.
The study looked at stroke risk before and after the time change and found a slight increase in stroke-related hospitalizations in the two days following the change to daylight saving time.
The increased stroke risk likely is related to interrupted sleep patterns, say the researchers, who are from University of Turku, Finland. The researchers are not sure what mechanisms are behind the increased risk, but note that previous studies have shown that shift workers and others whose sleep may be fragmented, also have increased risk for stroke.
In the study, researchers looked at stroke hospitalizations across Finland from 2004 to 2013. They compared the incidence of ischemic stroke, which are caused by blood clots in the brain, among 3,033 patients hospitalized during the week after the daylight saving transition with the stroke rate among a group of 11,801 patients hospitalized two weeks before and two weeks after that transition week.
They found that the incidence of ischemic stroke increased during the first two days after transition. The effect weakened after about two days, presumably as participants adapted to the change, the researchers say.
The researchers say it’s likely the transition to daylight saving time doesn’t create strokes where they otherwise might not occur; rather, the transition to daylight saving time makes strokes that are inevitable occur earlier.
Their findings were released Feb. 29 and will be presented at the upcoming American Academy of Neurology (AAN) 2016 Annual Meeting in April.
These findings shouldn’t scare everyone when it is time to change the clocks, but they highlight why it is so important for people to be aware of and manage their stroke risk factors, says vascular neurologist Zeshaun Khawaja, MD. Dr. Khawaja did not take part in the research.
“Some of the most common risk factors include high blood pressure, high cholesterol, diabetes, obstructive sleep apnea, smoking and a sedentary lifestyle,” Dr. Khawaja says. “In patients with stroke risk factors, it is important to manage sleep patterns because studies have shown it can impact a person’s stroke risk.”
While the findings did not show a direct cause and effect, they did affirm the results of previous studies that have shown that an upset in circadian rhythm can impact a person’s health, Dr. Khawaja says.
Knowing your health risks ahead of time can help you take extra steps to avoid complications from that sleep-wake cycle disruption.
Act quickly with stroke symptoms
Many people are unable to identify the symptoms of a stroke. To help people remember the signs, doctors like to use the term Be Fast, which stands for:
Balance — Loss of balance
Eyes — Changes in vision
Face — Facial drooping
Arms — Numbness or weakness in the arm or leg
Speech — Difficulty talking
Time — Get medical help immediately because time is of the utmost importance in treating stroke
Acting quickly if you suspect stroke is important, Dr. Khawaja says, because every second that is lost results in a loss of brain tissue.
“You lose about two million neurons per minute, so it’s important to know the signs and symptoms to stroke and to seek treatment right away. Time is brain and stroke is a medical emergency,” Dr. Khawaja says.
In addition to knowing the symptoms of stroke, Dr. Khawaja says it’s important to try to maintain a healthy lifestyle including regular diet, exercise, and sleep habits to help reduce the risk of suffering a stroke.
Stroke treatment guide