Semiannual time changes associated with accidents and heart attacks

As people set their clocks back an hour on November 3 to mark the end of daylight saving time and the return to standard time, they should be mindful of their sleep health and the potential risks associated with changes to their sleep patterns, according to the University of Calgary. professor of psychology who studies circadian cycles.

Notably, previous research has shown that changing time twice a year is associated with an increase in car accidents and workplace injuries, as well as heart attacks and strokes due to sleep disruption, said Michael Antle, Ph.D., chair of the department of psychology at the University . University of Calgary and member of the Hotchkiss Brain Institute at the Cumming School of Medicine.

In an interview with Medscape Medical NewsAntle explained the science behind the health risks associated with time changes, offered tips for preparing for the shift, and discussed scientists’ proposal to move to year-round standard time. This interview has been condensed and edited for clarity.

Why is it important to pay attention to circadian rhythms?

Circadian rhythms are patterns of physiological and behavioral changes that affect everything inside the body and everything we do, including the release of hormones, the readiness of digestive juices for digestion, and the release of growth hormones at night. The body is a carefully orchestrated orchestra, and everything must happen at the right time.

When we begin to interfere with these rhythms, then painful conditions begin to appear and we feel unwell. You’ve probably experienced this—when you’re trying to stay up late, eating at the wrong time, or experiencing jet lag. Flying across one or two time zones is usually tolerable, but if you’re flying across the world, it can be stressful and leave you feeling sick for even a week. Similar shifts occur with changes in time.

How do changes over time affect health risks?

Daylight Saving Time tends to be more bearable, and you’ll hear people talk about “gaining an hour” of sleep. It’s even better because we adjust our social hours—like work schedules and school schedules—to account for daylight. We tend to go to bed relative to the sun but wake up based on when our boss tells us to be at our desk, so an earlier sunset helps us fall asleep earlier and is better for our bodies.

In spring, the opposite happens, and the change in time affects us much more than just one sleepless night. For some people, it may feel like we’re losing an hour of sleep every day for weeks, and this sudden change can lead to car accidents, workplace injuries, heart attacks and strokes. Our body experiences extra stress when we are not awake and ready for the day.

What does your research show?

Much of my work focuses on preclinical models to understand what happens in the brain and body. Since we can’t ethically study this in humans, we learn a lot from animal models, especially mice. In a recent study looking at mild circadian rhythm disturbances (where we raised mice on days that were about 75 minutes shorter), we saw that they began to develop diabetes, heart disease and insulin resistance for a few months or so around the time they were young adults.

People often think of their sleep rhythm as an arbitrary choice, but it actually affects your health. We know that if your human circadian clock is slow, morning light can help correct this and reset it, whereas evening light moves us in the other direction and makes it harder to get up in the morning.

Some people want to switch to one year-round season. What are you protecting?

In most cases, standard time (or standard time) is a more natural time that better suits our body’s cycle. If we track the times when we get up before the sun or go out late, it is associated with greater social jet lag, where people are less attentive at work, do worse in school and have more accidents.

Instead of choosing what sounds good or chasing a name (like “daylight saving time”), we need to think about the right time for us and our circadian clock. Some places, such as Maine in the US, actually correspond better to the Atlantic time zone or the Maritime provinces in Canada, while some parts of Alberta are geographically located west of Los Angeles in longitude and correspond better to the Pacific time zone. . Sticking to year-round daylight saving time in some Alberta cities would mean people wouldn’t see the sun in the winter until 10:30 a.m., which is very late and could impact activities like skiing and hockey.

Canadian Society of Chronobiology advocates year-round standard time aligning our social clock with our biological clock. Sleep and circadian experts in the US and around the world have made similar statements.

What tips do you offer to help people adjust their circadian clocks in November?

For people who know their body and know it will affect it more, give yourself extra time. If your schedule allows, plan ahead and change your clocks earlier, especially if you have the opportunity to do so on the weekend. Don’t rush when you are tired: Rushing when you are not ready leads to more accidents on the road or at work. Know that the sun will still be a little out of alignment and your body clock will take time to adjust, so you may feel groggy for a few days.

Antle reported no relevant financial relationships.

Carolyn Crist is a medical and health journalist covering the latest research for Medscape, MDedge and WebMD.