By Jacqueline Toomey
The heart of the fire service is what makes its members so great. In a sad bit of irony, cardiovascular events continue to threaten the livelihood of our nation’s heroes. But why?
Thankfully it’s being talked about more and more. From stunning Ted talks by Dr. Matthew Walker to books such as Sleep Revolution, we as a culture are waking up to the need for more sleep. The cost of sleep deprivation is a direct hit on our cardiovascular health. Of a total of 627 firefighter line-of-duty deaths (LODDs) reviewed in a 2018 study, 276 were cardiac related, or 44 percent. Only 16 percent of these cardiac cases displayed postmortem evidence of intracoronary thrombus, meaning most of these cardiac fatalities were not the direct result of myocardial infarction (MI).
Sudden cardiac death has maintained its position as the leading cause of LODDs despite national attempts to correct a longstanding pattern of diminished heart health in the fire service. Fire departments across the country have made efforts to improve nutrition, decrease smoking as a culture, and refocus physical training with an emphasis on cardiology. What are we still missing?
Research suggests that chronic stress, primarily from the body’s response to irregular sleep patterns, and long-term lack of quality sleep is now being linked to the hardening of arterial walls and overall enlarging of the heart (coronary heart disease (CHD) and left ventricular hypertrophy (LVH)). It wasn’t long ago that previous generations, such as our grandparents and great grandparents, had at minimum 1.5 hours more sleep than our current generation. Many of the firefighters that I work with report sleeping only four or five hours and consider that normal. In his book, Why We Sleep, Dr. Matthew Walker sites a study of 4,000 male workers that found that, over a 14-year period, “those sleeping six hours or less were 400- to 500-percent more likely to suffer one or more cardiac arrests than those sleeping more than six hours.”
Furthermore, the demand and call volume in the fire and emergency services has continued to rise. Consequently, as sleep, rest, and recovery have taken a back seat to personal and professional demands, rates of cardiovascular disease, and lifestyle-based illness have skyrocketed. The evidence is overwhelming: sleep loss is killing firefighters and causing severe cardiac strain to the point of mortality. The time has come to implement the next critical phase of cardiac preservation and protection: Sleep recovery practices and a new lens at restoration.
When my firefighter husband Sean and I first started dating, he shared with me fire service health statistics. It was curious and odd that an industry of seemingly healthy and fit men and women could be dying from cardiac problems. Firefighters were passing away at alarmingly high rates but also at early ages. Even my father-in-law, who was a “fit” firefighter and exercised religiously, nearly lost his life to a severe cardiac event mid-career in his 40s. This event resulted in a quintuple bypass.
Thankfully he survived what heart surgeons referred to as the most severe left anterior descending (LAD) blockage they had seen in their career. He recently retired after 37 years of service to the Aurora Fire Department.
What exactly is happening to the heart when an individual experiences chronic sleep loss over a couple of years or a few decades?
Humans are naturally diurnal beings; unlike nocturnal animals, our chemical and hormone physiology aligns with the rise and fall of the sun. The circadian rhythm gives a pattern to the hourly release of certain hormones and neurotransmitters which dictates whether our body is in a state of conscious wake or restorative sleep. In Latin, the word circadian means ‘about a day.’ Sleep scientists have confirmed that our circadian rhythm isn’t exactly aligned to the 24-hour cycle of our day and nights, although it is nearly perfect: every time special receptors in our eyes and skin receive sunlight each morning, our rhythm is recalibrated and we are in sync with the time zone in which we live.
Understanding how the sleep cycle works is helpful knowledge to improve your health at large. Five different types of sleep occur in a cyclical pattern every 90 minutes on average. The first few stages decelerate the systems in the body and healing begins. The deepest phase of sleep is Stage 4, and it is critically important for heart health. It is known as delta brain wave sleep or deep sleep. Intense physiologic repair occurs for muscles, tissue, and organs such as the heart. If the body is woken from sleep every 45 minutes to an hour to run a call, no matter how short the emergency is, the body will inevitably have to restart the cycle through the lighter phases of sleep. In one night, it is possible that a person may never receive the benefits needed for optimal heart health. Midway through the night is when the resting heart rate is at its’ lowest of the day, and not receiving ample time in this mode is akin to running the engine of a machine 24 hours without shut down… eventually it will blow.
Data published by the American College of Cardiology shows how sensitive the human circadian rhythm is in its relationship to heart health. In the largest study of its kind in the U.S., researchers found that there is a 25-percent increase in the number of heart attacks nationwide that occur the Monday after we “spring forward” for daylight savings compared to other Mondays in the year. Interestingly, when we gain an hour back, there is a 21-percent drop in the number of heart attacks in the United States. Circadian rhythms are present in all mammalian species, in almost all organs and tissues. They are known as “intracellular molecular clocks” and their vital function is to prepare for activity based on external stimuli, making them responsible for regulating all bodily processes for physiological, metabolic, and behavioral life activities. The primary circadian master clock is found in a group of cells in the hypothalamus, named the suprachiasmatic nucleus (SCN). The secondary circadian clock is the “peripheral clock” found in all tissues, including tissues in the central nervous system (CNS). Our rhythms can be entrained by external stimuli, such as the use of bright blue light in the morning to stimulate sunlight (this is helpful for people in times zones who have darkness in many months of the year), and darkness at night, which triggers the sleep hormone melatonin.
Equally important is that external artificial stimuli can desynchronize the circadian rhythms. The use of bright light at night and exposure to screens at night are so harmful to health: by engaging in these activities, you will accidentally cause cortisol production at night, the time it should be lowest. The medical report “Shift Work and its Effects on the Cardiovascular System” states: “The cardiovascular system in all mammals is highly organized with regard to time.
Epidemiological studies have clearly documented that cardiovascular-related events, such as myocardial infarction, stroke and arrhythmias have the highest incidence of morbidity and mortality in the early hours of the morning, as opposed to occurring randomly.” It turns out every study since the 1980s (when shift work was first being investigated) has unanimously concluded that those who perform shift work have a higher risk of developing cardiovascular disease.
Stress Hormones, Weight Gain, and the C-Reactive Protein
The degradation of our heart health begins with the rise of stress hormones that spike every time a person is woken at a time that is not natural (in other words, any time a first responder runs a call in the middle of the night). Because we are hard wired to be asleep at night, in safety, when the body is randomly woken, its internal system that scans for danger kicks on with the assumption that there is probable danger in our midst and the body prepares for fight or flight. This activation is called the sympathetic nervous system response and floods the body with ample amounts of glucose in the bloodstream for energy. It also increases the heart rate for action and halts all activity in secondary systems, such as digestion, growth hormone rebalancing, and cellular immune repair. The adrenal hormone that causes these effects is called cortisol. Another important effect of the sympathetic response is the release of adrenaline and norepinephrine (also called noradrenaline). Noradrenaline puts the brain under a chemical influence to remain hypervigilant, alert, and active. An interesting fact about sleep in relation to noradrenaline is that the only time in the 24-hour cycle of a day that the body completely shuts down the production of NA is during rapid eye movement sleep (REM), the last phase of the sleep cycle. Individuals who experience chronic hyper-activation of the sympathetic nervous system, or have conditions such as post-traumatic stress, will often have heightened levels of these hormones, which prevent this critical stage of sleep for psychological healing. It may cause interrupted, tossing-and-turning types of sleep. These lingering stress hormones also cause wakefulness during the hours of midnight and 4 a.m., extremely common amongst the firefighters I work with.
Weight gain is a direct result from elevated stress hormones, too, specifically due to cortisol. In survival mode, the body essentially slows down metabolic function for conservation purposes. The body, in its effort at self-preservation, dials up ghrelin production in the body, which is a hunger hormone. Ghrelin’s influence can be so strong it can hijack your diet plan and cause you to eat out of impulse. Its inverse hormone, leptin, is the signal to the brain to stop eating once satiation has occurred. You recognize leptin putting on the brakes to reach for more after the last serving of Thanksgiving dinner. Unfortunately, whenever the body is sleep deprived, leptin’s volume is dialed down to a mere whisper. What ensues is the perfect recipe for diet fails and indulgence in the wee hours of the night. I mean, what do you see people in the firehouse reach for after running a call in the middle of the night? One study shows that individuals who stay up really late at night tend to consume an additional 300 to 1,000 calories per day. Sleep loss causes increased caloric intake, but worse, the types of calories will be more likely from starchy, sugary foods that have low nutritional benefit and will likely be caked on to the abdomen or neck area as fat stores. If only we could rewire our evolutionary fight-or-flight response to recognize running a call at night is not the same grave danger of famine or drought that our ancestors potentially faced…
This weight gain caused by sleep disruption has serious consequences for heart health. And what is worse is it has a double-edged sword effect: sleep loss causes weight gain, and excess weight gain causes sleep disorders like sleep apnea, which precipitates more sleep loss. In an examination of sleep health on firefighters from 66 US fire departments, Harvard researchers discovered that sleep apnea was the number-one sleep disorder in the fire service, followed by insomnia and work shift disorder. Unfortunately, 80 percent of the firefighters who screened positive for one of these sleep disorders had no prior diagnosis or awareness. It was also found that those same firefighters were more likely to report having heart issues. This is a critical correlation as one study showed over an eight-year period, men with severe sleep apnea were 58 percent more likely to develop congestive heart failure. Every fire department should have mandated sleep disorder screening, especially for sleep apnea. When I discussed this with my husband, he said it would be unlikely to get departments to require that because of the associated costs. He’s right, but monetary costs should not factor in when estimating the value of saving a life. That said, the cost savings for this test is a no-brainer in comparison to the massive amounts cities pay annually for medical insurance claims because of cardiac arrests on the job.
Congruent to the body’s stress hormones is accompanying inflammation. Inflammation is considered the root of all disease, and according to Phyllis Zee, MD, PhD, professor of neurology and director of the sleep disorders program at Northwestern University’s Feinberg School of Medicine, shortened sleep can increase C-reactive protein (CRP), which is released with stress and inflammation. She states: “If your CRP is high, it’s a risk factor
for cardiovascular and heart disease.” The presence of the C-Reactive Protein is caused by various health issues, anything from infection to cancer. High CRP levels are a potential warning that there’s inflammation in the arteries of the heart, which can mean a higher risk for heart attack. This is why many doctors such as Dr. Satchin Panda, who works with the Sand Diego (CA) Fire Department, and health professionals such as myself promote eating an anti-inflammatory diet for firefighters. This includes Omega-3 fatty acid rich foods such as certain types of fish and other nutrient dense foods that promote healing.
Solutions to Combat Sympathetic Activity
To mitigate these risks, we must reverse the effects of the sympathetic nervous system. This can be accomplished by learning how to engage the parasympathetic nervous system, also known as the relaxation response. Unlike the short-term survival mechanism of the sympathetic nervous system, the parasympathetic nervous system is responsible for our long-term health and wellness. Many people feel the effects of the fight-or-flight response and are out of balance, sleep deprived, anxiety ridden, and not able to downregulate from these heightened stress experiences. Some self-medicate and turn to substance abuse to feel better.
That is why learning practices that engage the relaxation response in the body are true tools that empower a person’s mental and physical well-being. Parasympathetic nervous system practices can be accomplished in as little as a few minutes and
done at any point in the day. Simple breathing techniques, progressive muscular relaxation, and stretches that release the fascia are simple methods to switch nervous system gears.
True, deep relaxation is not a common experience for the general population, who may only experience it once per year on an annual vacation. But it shouldn’t take a nap in a hammock under a palm tree and the sound of lapping ocean waves to activate this state of being; in fact, it should be activated once if not multiple times per day for optimal health. The good news is that it is remarkably easy to access once you learn effective ways to train your body to achieve this health-promoting state.
One of the most effective tools for engaging the parasympathetic nervous system and promoting good sleep is the primary practice I teach in the First Responder Sleep Recovery Program. It is a simple, guided relaxation derived from an ancient meditation called Yoga Nidra. This effortless form of relaxation has been tailored for first responders into an integrative practice known as the Sleep Recovery Practice™. Yoga Nidra has been studied by various research institutions as a means for mind-body healing and renewal. It promotes better sleep quality, improves circadian patterns, and research has found that it lowers cortisol levels effectively and increases endogenous production of dopamine by 60 percent. I have taught it to fire departments at conferences and firefighters in 10 states. Studies show that after one 30-minute practice, the blood pressure decreases, the heart rate lowers, brain wave activity improves, and stress hormones decrease. In data collected in feedback forms between 2017-2018 of over 500 firefighters who experienced the guided Sleep Recovery Practice, more than 90 percent report the experience had a positive effect on how they felt cognitively and physically, and felt it was an experience worth recommending to other first responders. The top five descriptors of first Sleep Recovery Practice after firefighter’s first, introductory experience was described as: “Amazing!” “easier to fall asleep,” “clear minded,” “relaxed and re-engergized,” and “refreshed.”
There’s no question as to why Walter Reed National Military Medical Center uses the practice for military and veterans who are healing from post-traumatic stress, anxiety, depression, and sleep disorders: it works. In 2010, through research by Dr. Richard Miller and Walter Reed, yoga nidra was officially endorsed by the U.S. Army Surgeon General and Defense Centers of Excellence as a complementary and alternative medicine.
There are many other ways to activate the parasympathetic response and one of the easiest ways is to find and connect with the activities and relationships that truly bring you joy. Joy has been lost in our day to day experience. It’s understandable when we are inundated with news headlines saturated with death and horrible things. Increasing call volume adds more stress and less time as a crew to bond and recover the good old fashion ways. To compound things, our most recent societal pastime is using our thumbs to scroll social media, which is a littered sub-reality of our lives. Joy
must be found in our relationships, where we feel connected, pleasure, and simple happiness. We need to spend more time outdoors engaged in physical leisure, like bicycling with our kids, hiking, camping, chopping wood, fishing, and telling stories by the campfire. Haven’t you ever noticed how genuinely good and reset you feel after a camping trip in nature?
In the same way the cardiovascular system requires exercise to stay fit and healthy, there is a flip side of the coin: the heart needs restoration and the emotional heart needs to be reset each and every day. Our overall well-being is reliant on our ability to bring balance back to our lifestyles.
There are measures to counteract the effects of sleep loss. The key in doing so is learning how to activate the parasympathetic nervous system and obtain the rest, renewing, healing response for our autonomic nervous system. Why aren’t more people doing it? Let’s bring sleep back to the heart of the fire service.
Denise L. Smith, Jeannie M. Haller, Maria Korre, Patricia C. Fehling, Konstantina Sampani, Luiz Guilherme Grossi Porto, Costas A. Christophi, and Stefanos N. Kales. “Pathoanatomic Findings Associated With Duty‐Related Cardiac Death in US Firefighters: A Case–Control Study.” Journal of the American Heart Association. September 2018.
Jacqueline Toomey co-created the First Responder Sleep Recovery Program with her firefighter husband, Sean Toomey. She received her B.A. from Regis University, completed masters-level coursework in education at Metro State University, and trained in Nutrition Therapy. As a three-time Yoga Alliance certified instructor, Jacqueline integrates various modalities for mind-body healing in an accessible and effective way for first responders. The Toomeys are honored to teach at departments, conferences, and locals across the United States and Canada.