Chronobiology

Most modern people will have a surgery—even a minor one—at some point in their life. In fact, many people have several major surgeries as well as a few minor procedures over the course of their lifetime. Although the vast majority of these surgical procedures will end with a safe and complete recovery, there are still rare bad outcomes. According to a new study, the timing of surgery may have a measurable impact in how patients recover from surgery and whether they get the outcomes that they desire.

How Common Are Surgical Complications?

Although most of the millions of people who undergo surgery every year have a full recovery with the desired outcome, complications and poor outcomes remain a potential side effect of most medical procedures. Only around 2 to 4 percent of surgeries have complications of any kind, which can include blood clots, excessive bleeding, infection and surgical failure.

The complication and failure rates of American surgeons are public knowledge through a variety of websites, leaving surgeons with ample motivation to decrease these statistics. Many new policies have cut back complications to the point that many surgeons have a 0 percent rate. Despite this, infection and other complications remain a possibility. What if we could reduce these complications simply by changing the time of day when surgery is performed?

Does the Timing of Surgery Matter?

Surgeries are often planned to begin early in the morning and lasting much of the day. Most surgeons will perform several surgeries, even major ones, on a typical workday. Many people might assume that surgeries performed later in the day have worse outcomes. After all, it’s reasonable that the surgeon could be getting tired by early afternoon. However, new research on how the time of day affects surgical outcomes suggests that just the opposite is true.

Scientists held a randomized controlled trial to examine if and how the time of surgery correlates with outcomes. Half of the patients were scheduled to have open heart surgery were scheduled for the morning and the other half for the afternoon. The results were surprising: Patients who had surgery after lunchtime were half as likely to have certain complications, including serious ones such as heart attack, heart failure and death.

How can timing affect surgery so much? People who have open heart surgery often do so because they have a blockage or other damage from loss of blood flow to the heart. This means that they are susceptible to ischemia-reperfusion injury, which is damage that occurs when adequate blood flow is restored. For some reason, this type of injury is less likely to occur in the afternoon hours. Doctors and scientists are not sure why this type of injury appears to be affected by the time of day. However, patients who need this type of surgery may benefit from having it in the afternoon.

The Interaction of Circadian Rhythm and Medicine

This is not the first correlation to be found between the timing of medical care and outcomes. Previous research has found that vaccines are more effective when given in the morning. Cancer drugs similarly appear to be most effective when given at the times of day when cancer cells are most metabolically active.

Even simpler treatments such as blood pressure and diabetes medications appear to work better when timed right. People can take less of these drugs and get the same or better results with less risk of side effect simply by changing the time of day when they take them.

Chronotherapy: The Future of Medicine

There are currently only a few medications and treatments that are routinely given only at the time of day when they will be most effective, have fewer side effects or otherwise have an additional benefit. However, this practice, known as chronotherapy, may be the future of medicine.

Our bodies run on a complex set of internal clocks. Not only is there a master clock in the brain that coordinates our body’s internal clocks with external cues, but there are also clock mechanisms in every organ and even every cell. When it comes to biology, timing is everything. Thanks to recent discovering in chronobiology, modern medicine is beginning to get in sync with these clocks. Patients can take medications at times of day when they will be metabolized most safely or have fewer side effects. They can choose to target very specific metabolic actions, leading to a complete treatment. While chronotherapy is still a new concept, it is easy to see how it may someday change much of what we currently know about medicine.

Patients currently have little choice over when they have surgery, especially an urgent one like heart surgery. However, there may be benefits to waiting until after lunch for surgeries with more flexible times. Although we still do not know why our organs appear to heal better from surgery in the afternoon hours, timing does appear to make a huge difference in outcomes.

When it comes to the concept of “daylight saving,” modern people simply accept the twice-annual change in time as a fact of life. However, like many aspects of modern life, daylight saving may have serious negative effects. For many people, the effect is similar to jet lag, a movement across different time zones. They suffer fatigue, difficulty sleeping and other mild effects that slowly pass. Other people may have more serious—even life-threatening—effects. Could springing forward and falling back actually be a risky decision for our country?

The History of Daylight Saving

Daylight Saving Time (DST) was not a reality for most of human history. The famously frugal Benjamin Franklin was the first to propose turning clocks to allow more light in the actual day, but this idea did not come to fruition for more than a century. Germany adopted the practice of changing clocks twice a year as an energy-saving measure in World War II. Many countries followed suit due to the obvious practicality.

Does this practice actually save money? In most areas it does; around 1 percent. However, in warm areas such as Florida, it appears to actually lead to more energy usage, as it reduces lighting needs while increasing the need for more expensive air conditioning. Daylight Saving Time likely leads to a very small overall cut in energy needs. Is that enough to justify the practice?

Could Changing the Time be Harmful?

Any savings in energy would be worth the change if it came at no cost whatsoever. However, a growing body of work suggests that this practice may have serious economic and physical costs. Light is one of the major cues for regulation of our circadian rhythms, so it makes sense that changing our sleep-wake cycle in relation to daylight hours could have consequences.

Several studies have indicated that daylight savings time may be a very expensive habit. Accidents, both in vehicles and on the job, increase sharply the next day. In addition, there is an immediate increase in strokes, heart attacks and a variety of other serious health problems: Even with the change back to standard time, the biorhythm gets confused. Is this huge cost worth the difference in energy expenses? Many countries such as Finland are discussing giving up daylight saving due to its destructive effects on citizens.

How Our Bodies Process a Time Change

As mentioned before, our internal clocks process a time change as a type of jet lag. Suddenly, external cues no longer line up with our own internal schedules. There are several factors that can make this phenomenon better or worse. For example, most people suffer more with the springtime change than the one that occurs in the fall. This is because the spring change generally involves missing an hour of sleep every night until our internal clocks have adjusted to the change. Fall, on the other hand, is easier to adjust to because people are gaining sleep, which most modern people need desperately.

In addition, a person’s chronotype (whether they are a so-called early bird or night owl) also can have an effect on how they react to the time change. In general, night owls or late chronotypes do not adjust as easily or quickly. This is likely due to the fact that they are already getting up as late as they comfortably can, so a time change means a substantial loss of sleep. Early birds, on the other hand, can simply be a little less early for a few days until their internal clocks adjust.

Surviving and Thriving Through Time Changes

There are several ways that people can keep the upcoming time change from having negative effects on their health and their lives. Consider the following options:

• Begin adjusting your bedtime by 15 minutes a night for a week before the time change. Your body will react better to a gradual change.
• Avoid eating—even a snack—in the hours before bed. Eating is a cue that you plan to be awake for a while.
• Avoid caffeine, alcohol and other substances in the few hours before bed.
• Get plenty of exercise and exposure to bright light during the day.
• Avoid screens, televisions and bright lights in the two or three hours before bed, as light will delay the release of melatonin.
• Consider taking a melatonin supplement just before bed if you struggle to fall asleep at your new bedtime.

In addition, it is important to make a sleep schedule and stick to it. Refuse to sacrifice sleep for work, study or social activities. In addition, avoid taking a nap during the day, even if you are very sleepy. Getting up and going to bed at the same time every day is crucial to developing a stable sleep-wake cycle.

Daylight Saving may not be the healthiest concept for most people. However, it remains a fact of life. If you are struggling to turn your internal clocks forward or backward every fall and spring, there may be ways of helping your body to adjust. Talk to your doctor if you are having trouble even with simple lifestyle choices.

Pregnancy brings with it a long list of aches, pains and inconveniences. One common complaint is that sleep can become more difficult. While most discomforts in pregnancy pose no risk of harm, a new study suggests that sleep disorders may increase the risk of preterm labor, which can in turn have very damaging effects on the unborn child. How does sleep affect a growing fetus? How can mothers safely get the rest they need?

Sleep Disorders During Pregnancy: A Common Problem

While most people know that sleep becomes elusive after birth, few realize that the sleepless nights begin in pregnancy for many expectant parents. Sleep disorders actually are incredibly common in pregnancy. Women who have never struggled to sleep may find that they suddenly have issues. Those who already had sleep disorders may see these worsen. This is due to several factors. First, emotional and physical stress increase sharply during pregnancy. Second, snoring, sleep apnea, restless leg syndrome, heartburn and other disorders that interfere with sleep become much more common.

Last, and perhaps most importantly, the second and third trimesters of pregnancy can bring a great deal of discomfort that interferes with sleep. Women are extremely limited in their positions and have difficulty getting comfortable. Pressure on the bladder forces many to use the bathroom several times throughout the night. With all of these physiological changes, it is amazing that any pregnant woman gets adequate sleep. However, getting enough sleep may be much more important that we previously realized.

Could a Sleep Disorder Affect an Unborn Child?

Researchers looked at the sleep habits of women who went into preterm labor compared to those who gave birth at full term. Even when adjusted for other risk factors, women who had sleep disorders were far more likely to give birth early. The differences in preterm labor risk were substantial; women with insomnia were 30 percent more likely to go into preterm labor, while those with sleep apnea had a 50 percent higher risk.

This poses a significant risk to unborn babies. Preterm infants are more susceptible to infections. They struggle to gain weight and may not even be physically mature enough to breathe unassisted. If born in the second trimester, the risk of death and lifelong disability are substantial. Preterm birth is the leading cause of death worldwide for children under five years of age. Even when premature babies survive and thrive, medical costs for their care can easily add up to millions of dollars.

New Connections: The Importance of Sleep in Pregnancy

How can sleep disorders have such a devastating effect on the health of both mother and child? The connections are likely multifactorial. Snoring and sleep apnea increase the risk of hypertension, pre-eclampsia and gestational diabetes, all of which have been linked to preterm labor and other pregnancy complications. Apnea, or stopping breathing for short periods while sleeping, can also reduce oxygen flow to the placenta and the fetus.

Sleep disorders also appear to affect levels of growth hormone in the fetus. This can affect the infant’s growth and development. Melatonin, which may be deficient in people with sleep disorders, has been found to be particularly important in fetal brain development. Because fetuses cannot make melatonin, low levels in the mother could potentially have a lifelong effect. Clearly sleep is very important both to the mother and her developing child.

Helping Pregnant Mothers Get the Sleep They Need

This new knowledge about the effects of sleep disorders during pregnancy may be concerning to the many pregnant mothers struggling to sleep. However, there are natural, safe solutions that can help many people to get the sleep they need. Consider the following strategies for getting a solid night of rest while expecting:

• Start pregnancy at a healthy weight, which lowers the risk of snoring and apnea.
• Eat a snack high in potassium before bed if leg cramps wake you.
• Turn off screens in the hour before bedtime.
• Use pillows to help achieve a more comfortable and supported sleep position.
• Get gentle exercise during the day.
• Eat a high-protein or high-fiber snack before bed to keep your blood sugar levels steady.
• Engage in relaxing activities before sleep, including meditation, yoga or even a warm bath.
• Leave enough time in your schedule to get ample sleep, even allowing for more nighttime awakenings.
• Talk to your doctor or midwife before trying any sleep medications or supplements.
• Keep your health care providers apprised of any snoring or difficulty sleeping.

Like many discomforts during pregnancy, there are ways to safely treat sleep disorders. Getting enough sleep is essential to the emotional and physical health of both mother and child.

Sleep is a challenge for most parents. However, it appears that these challenges begin even before the baby is born. While it can be difficult to get enough sleep in pregnancy, doing so may help to prevent very serious disorders in the fetus. Pregnancy is a time for self-care, pampering and plenty of rest.