Into the Nightworld – The Science of Sleep
Sleep apnea seems the stuff of nightmares. It can sour mood and stunt memory. It cranks up high blood pressure. It raises the risk for diabetes and heart disease, and can increase your chances of being in a car accident. It keeps loved ones awake. It plagues people of all ages. In serious cases, it can result in depression, brain damage and death. By all accounts, it’s on the rise. And it often goes undiagnosed.
According to the National Sleep Foundation, more than 18 million adults suffer from obstructive sleep apnea (OSA). While we have struggled to deal with the problem nationally, the Merrimack Valley has stood at the forefront of the health care industry for the treatment of OSA and other sleep disorders.
Among the pioneers in the field is John Murray, the coordinator of Northern Essex Community College’s sleep technology program, which was launched in May 2008 in part to meet insurance and market demands for certified sleep technicians. Until that point, hospital sleep labs often relied on EEG or pulmonary technicians, or workers with on-the-job training.
According to Murray, NECC started the first accredited program of its kind, and there are now about 35 others around the country — still not enough to meet national demand. The urgent need for sleep techs benefits the program’s participants. On the day we met, Murray had received news of a student who had been hired full time.
To understand why the sleep health landscape has changed so much over the past few decades, it’s important to realize that sleep science is a relatively new discipline. Although it seems hard to believe, rapid eye movement (REM) sleep wasn’t discovered until 1953, and we only recently have begun to understand the role of sleep and sleep stages in general health and wellness.
Murray explains, “We have three states of being. … Awake, non-REM sleep, and REM sleep, and we need all of them to be a healthy person.” These stages allow the body to perform different functions. For example, during delta sleep, a period in which the brain waves slow down considerably, vital growth hormone is released.
Sleep plays other roles, as well.
“We lose connection with the autonomic system in REM sleep, so the heart rate can become variable. Breathing becomes variable. … And the brain all of a sudden becomes active,” Murray says. “There are a few theories floating around about why this is the case. This might be when we reorganize our thoughts, almost like a computer rebooting. Everything gets cleared out. We know that people who have a decreased amount of REM tend to have memory problems.
“There’s a cycle within sleep.” Murray continues. “About every 90 minutes we have an REM period. As night progresses, deep sleep decreases and REM sleep increases. This is why we have four or five dreams each night, but we only tend to remember the one we woke up from.”
The healthfulness of our sleep is closely related to the way our brains operate as a sort of timer or clock, controlling these regular patterns of brain and hormonal function.
“There’s this connection between our eyes and our hypothalamus — the retina and the retinal tract,” Murray says, referring to the sleep regulating region of the brain. “There are two major hormones that control this clock. There is cortisol, which is the hormone of wakefulness, and then there’s melatonin, which is the hormone of sleep.”
Problems occur when stress, drug abuse, obesity and other factors disrupt the regular push and pull between cortisol and melatonin.
Murray says light plays a critical role, and I heard this refrain again and again from experts. The role of light isn’t surprising, given the connection between our eyes and our brain’s internal clock.
Keeping a regular sleep schedule is also important. “Napping or going to bed too early can be a problem.” Murray says, and explains that during naps, you skip over the earlier stages and go right into either deep or REM sleep. “So what are you left with for the rest of the night? The lighter stages of sleep. That’s why they say naps should be 20 minutes at the most.”
So how much sleep do you need?
“You need enough so that when you wake up, you feel rested,” Murray says. “For some people, that might be six hours.”
While the most common sleep disorder is insomnia, for sleep technicians and health care professionals, sleep apnea is the condition they are far more likely to treat. OSA, which occurs when a person’s breathing is interrupted during sleep, is largely responsible for igniting the boom in sleep medicine.
Murray isn’t the only sleep technology pioneer working in the region. Yuan Zhang is an assistant professor in the Susan and Alan Solomont School of Nursing at UMass Lowell. She has published research on many topics in sleep science, including recent work on issues particular to correctional and elder care nurses. Zhang is currently studying sleep quality among nurses and the relationship between sleep and musculoskeletal disorders.
Zhang first became interested in the topic of sleep during the clinical stage of her nursing education. “I’m a nurse, and one of the primary health issues for the nursing population is sleep,” Zhang says. “I had moderate sleep issues with some symptoms of insomnia. … Now I know that is called shift work sleep disorder.”
This experience sparked her interest in figuring out what causes sleep problems in the nursing population and what kind of health promotion skills they can use to influence sleep quality. Zhang cites the importance of light and a regular schedule, and also the value of nonpharmacological means of sleep promotion such as yoga, meditation and mindfulness.
Zhang prefers an integrative, holistic approach to sleep health. “If you don’t sleep well, you might make poor food choices or avoid exercise,” she notes. Sleep also affects mood and interpersonal relationships. Lack of sleep can cause increased stress, which in turn can lead to poorer sleep quality.
This vicious circle may seem impossible to break, but just as negative factors are interdependent, so are positive. “Health habits connect with each other,” Zhang says. “If you are exercising, then you probably are eating healthy food.”
In the workplace, some companies are providing employees with activity trackers. Zhang says such devices are useful in promoting sleep awareness, but are only one way to inspire the sort of overall behavioral modifications necessary for optimal sleep health.
“New technologies like the iPad and the smartphones can be a problem,” Zhang says. “Adolescents are using those devices before sleep, and the light coming out from the devices is blue light. Blue light has been shown to suppress melatonin secretion. … Using those devices can shift their circadian rhythm to a delayed sleep phase.”
There are products on the market to help filter the blue light, from orange-tinted glasses to goggles for shift workers. However, Zhang prefers a simpler approach. She says, “It’s best to have 30 minutes to an hour of quiet-down time. Don’t watch the TV one hour before sleep. Read books or do quiet activities or meditate for 10 minutes to help your mind quiet down.”
Sometimes, keeping a consistent schedule is difficult or impossible. Such is the case with shift workers, but we also see the problem among parents. Zhang’s family sleep schedule has been disrupted by the arrival of a new baby. She says research indicates that women can experience significant hormonal disruptions following childbirth, which can lead to poor sleep.
To illustrate how our awareness of sleep health is changing, Zhang explains that Healthy People 2020, a federal government initiative that sets decadelong agendas for national health objectives, has added sleep health as a target area. Managed by the Office of Disease Prevention and Health Promotion at the U.S. Department of Health and Human Services, Healthy People 2020 aims, among other things, to get more people with OSA symptoms to seek treatment.
Working on the frontlines of OSA treatment is Dr. Ramesh Donepudi, medical director of Lowell General Hospital’s Sleep Lab and Neurodiagnostics Center.
Donepudi, whose initial training was in pulmonary and internal medicine, was drawn to the study of sleep because of his own experiences. “It was personal for me. I have sleep apnea, too,” he says. “I kind of knew I had this problem years ago, and one thing led to another.
“Sleep is not a specialty that is confined to one field,” Donepudi adds. “Traditionally, pulmonologists have had a lion’s share of the sleep medicine world. That’s because the CPAP is a pulmonary device. It’s a blower, just like a ventilator. … ENT [ear, nose and throat] doctors deal with a lot of sleep apnea. There’s an insomnia component, which is within the realms of psychiatry and neurology. Orthodontists play a significant role.”
While sleep medicine’s status as a multifaceted field may be due to its newness, the condition itself demands a complex approach to treatment. “Sleep apnea is a problem of three things,” Donepudi explains. “There’s a problem with structure, the tone of the muscles and one of tissue. You have to figure out what is the most prominent one. Is a structure problem, is it a tone problem, or is it just a problem with [the patient’s] weight? There’s a big misconception that it’s all a weight problem. It’s not.”
I realized I was guilty of this misconception myself. When Donepudi says he suffered from sleep apnea, it was unexpected, as he is slender and fit.
I ask him what he believes is causing the rise in sleep apnea diagnoses: Is it increased awareness within the medical community or cultural conditions?
“It’s a little of both,” he says. “The field is now about 20 years old. There’s a lot of awareness, but we’ve reached a plateau stage as far as awareness goes. … We are definitely, as a society, facing an epidemic of obesity. That’s not helping things. Then there’s a third aspect. We have become sedentary and are not exercising as much. That plays a role, too.”
When it comes to important factors in everyday sleep hygiene, Donepudi, along with Murray and Zhang, stresses the value of light.
“We don’t realize the impact the light has, especially being in New England,” he says. “You need adequate light exposure.”
Are there factors that people find surprising?
“Alcohol, for me, is a big factor that’s not treated seriously as an inducer of sleep apnea,” Donepudi says. Alcohol relaxes muscle tone, a problem for those suffering from OSA. What’s more, “Alcohol helps you fall asleep, but it actually disrupts your sleep in the second half of the night. Once the alcohol wears off, you have a rebound and experience sleep arousal.”
Along the lines of alcohol, I ask Donepudi if he foresees any sleep-related benefits or problems connected to the shifting medical and recreational marijuana laws. He is not sure what the widespread effects of legalized marijuana will be on sleep, but he’s not optimistic.
Based on my talks with Murray, Zhang and Donepudi, I’ve boiled their advice down to a few key points.
1. Look to the light. Humans need adequate light exposure to maintain their circadian rhythms.
2. Exercise. From improving the muscle tone that can impact sleep apnea to reducing stress, exercise is critical.
3. Avoid drinking alcohol before going to bed.
4. Practice meditation and deep breathing. If you don’t have access to meditation classes, free or inexpensive smartphone apps are available.
5. Keep a regular schedule. The more consistent your sleep patterns, the better your sleep hygiene will likely be.