Insomnia affects 10% to 15% of people in the general population. But nearly 44% of people who have heart problems report frequent insomnia, making this one of the most common symptoms of heart failure.
The Link Between Insomnia and Heart Failure Risk
Insomnia is defined as difficulty falling asleep, difficulty staying asleep, or waking too early in the morning (or all three). Each was related to heart failure in a 2013 study. For people who had all three symptoms, the risk of heart failure was significantly increased—by more than three-fold.
Researchers aren’t certain why there is a connection between heart disease and insomnia, but there are two theories: The first is that there may be an underlying biological cause. The second is that the stress responses activated by insomnia take a toll on heart function.
Impact of Insomnia on Heart Health
Insomnia is known to increase the risk of heart disease (and stroke) in people who have the following conditions, all of which are regarded as precursors to heart failure.
High blood pressure (hypertension): During normal sleep, blood pressure drops. If you are unable to sleep, your blood pressure stays higher for a longer amount of time. High blood pressure is one of the greatest risk factors for heart disease and stroke. Type 2 diabetes: Diabetes is a chronic disease that affects how the body metabolizes glucose (sugar). Diabetes can damage blood vessels. Some studies show that getting sufficient high quality sleep may help improve blood sugar control. Obesity: Lack of sleep is associated with weight gain as it may affect the part of the brain that controls hunger, prompting eating during hours when you should normally be asleep.
Conditions That Interrupt Sleep
A number of conditions common in heart patients are known to impact sleep and can compound the severity of existing insomnia and sleep deprivation. You may need a sleep study (polysomnogram) to make a specific diagnosis, so your healthcare provider can initiate appropriate treatment.
Obstructive Sleep Apnea
Obstructive sleep apnea affects up to 50% of patients with heart failure. People with sleep apnea have prolonged pauses in breathing during sleep that can cause sudden arousal from deep sleep, often many times per night, leading to significant sleep deprivation. People with sleep apnea are often unaware of their nighttime arousals, and may not complain of insomnia—but they do experience many of the signs of sleep deprivation.
Sleep apnea tends to make heart failure worse and worsening heart failure often makes sleep apnea worse, creating a vicious cycle. It can be most effectively treated with a positive airway pressure (PAP) machine—a mask worn snugly over the nose, or nose and mouth, during sleep, that supplies pressurized airflow to prevent the airway from collapsing.
In studies, the use of CPAP machines (which provide continuous airflow) has been found to improve sleepiness, quality of life, and mood, as well as blood pressure, cardiac ejection fraction (the amount of blood the ventricles of the heart are able to expel with each beat), vascular parameters, and irregular heartbeats (arrhythmias).
Nocturnal Movement Disorders
Patients with heart failure are more likely than the general population to develop two kinds of nocturnal movement disorder that can interrupt sleep—restless legs syndrome and periodic limb movement disorder.
Restless Legs Syndrome
Restless legs syndrome (RLS) is characterized by leg discomfort during sleep, including burning, twitching, and/or creeping sensations that compel a person with the disorder to begin moving their legs around for relief (hence, “restless legs”). They will report involuntary sudden jerking or shaking of their legs that make it difficult to fall asleep.
Periodic Limb Movement Disorder
Periodic limb movement disorder (PLMD) is similar to restless leg syndrome in that it involves involuntary movement of the legs. The difference is the jerking or shaking occurs during sleep and so a person may not be aware it’s happening. Even so, it can disrupt deep sleep. PLMD often can be managed by avoiding caffeine close to bedtime, taking iron supplements (as for some people low levels of iron and folic acid are associated with the disorder), and taking medication to regulate muscle movements.
Treatment
Insomnia and sleep deprivation can take a toll on health and wellbeing, causing daytime sleepiness, fatigue, lack of energy, moodiness, and difficulty concentrating. Some tips for better sleep include:
Take Charge of Your Sleep Routine
Limit activities in bed to sleep and sex (no phones, laptops, or TV). Get up at the same time every morning, even on weekends. Go to bed only when sleepy. If you have not fallen asleep within 20 minutes, get out of bed and do something relaxing elsewhere under low light. Return to bed only when sleepy. Repeat. Don’t watch the time.
Monitor Your Sleep Hygiene
Avoid naps during the day. Avoid caffeine after noon. Avoid nicotine, alcohol, and heavy meals within two to three hours of bedtime. Create (and stick to) a relaxing bedtime ritual. Exercise during the day rather than right before bed. Get some sunshine during the day. Make sure your room is dark, quiet, and a comfortable temperature. Use earplugs or an eye mask if needed.