Two common sleep/pulmonary diseases are obstructive sleep apnea (OSA) and chronic obstructive pulmonary disease (COPD). These two conditions can occur simultaneously creating a condition known as Overlap Syndrome, which creates two fold the uncomfortable disordered breathing conditions, according to the American Sleep Apnea Association. It results in long-term chronic health issues that go beyond your lungs, like heart disease and diabetes, and their linked myriad complications.
Below we explain each condition individually, the signs and symptoms when combined, and the mortality of OSA and COPD Overlap Syndrome
What is OSA?
OSA, which stands for obstructive sleep apnea, is a sleep disorder that can be potentially serious. It causes breathing to stop and start repeatedly during sleep. There are a few types of sleep apnea, however, OSA is the most common. OSA occurs when throat muscles relax intermittently, blocking the airway while sleeping. Snoring is a noticeable sign of OSA.
Severely fragmented sleep results from this disrupted breathing pattern as individuals wake up enough to regain control over their throat muscle and reopen their airway. This continuous awakening means they are not obtaining either sufficient or good quality sleep, leading to fatigue and/or sleepiness.
But, since people remain partially or fully unconscious during an OSA episode, they likely don't even know what's causing their fatigue or sleepiness. And, along with fatigue and sleepiness, OSA can cause substantial psychological and physiological distress. It's a treatable condition and with the right diagnosis and treatment, many individuals have experienced full symptom resolution.
What is COPD?
COPD, which stands for chronic obstructive pulmonary disease, is a common lung disease. It's hard to breathe with COPD.
There are two primary types of COPD:
- Emphysema: Involves lung damage over time
Chronic bronchitis: Involves coughing long-term with mucus
The pathophysiology of COPD can progress from a simple cough to difficulty breathing. The effects of COPD on respiration while awake and during sleep may include:
Shortness of breath
People can often prevent COPD. A leading cause of COPD is cigarette smoking. Many individuals with COPD either smoke or used to. But, up to 25% of individuals with COPD have never smoked. Long-term lung irritant exposure to things like chemical fumes, air pollution or dust could also contribute to COPD. Alpha-1 antitrypsin (AAT) deficiency is a rare genetic condition that can also cause COPD.
COPD and Sleep
For around 40% of individuals with COPD, obtaining a decent night's sleep is often a huge challenge. The European Respiratory Journal published a 2002 survey that asked over 3,200 individuals with COPD in eight different countries about their disease. COPD is an umbrella term that encompasses both chronic bronchitis and emphysema, two incurable and progressive lung conditions that make it hard to breathe.
And it's this challenge of getting enough oxygen into the body that's likely what's causing the sleep disruption in individuals with COPD who say they're not sleeping well.
There are four common reasons that COPD can cause sleeping difficulties.
- People with COPD are susceptible to oxygen level drops at night, particularly while they are dreaming. This could be because during the day, they may be using more of their accessory muscles to help them breathe and during sleep, these accessory muscles are usually paralyzed.
- Alcohol, caffeine and cigarette smoking can disrupt sleep or compound a pre-existing sleep problem. Individuals might be obtaining poor sleep and then are tired in the daytime, so they compensate by drinking coffee or taking caffeine products to stay awake. They might be consuming alcohol at night to help them fall asleep. However, once the alcohol wears off, it can wake you up because it acts as a stimulant. Cigarette smoking acts as a stimulant as well.
- Depression and anxiety are common among individuals with COPD and these conditions can negatively disrupt sleep patterns.
- Some individuals with COPD also have sleep apnea, which turns into the condition overlap syndrome. A minimum of 10% of individuals with COPD also suffer from sleep apnea. This is a bad combination, since it duplicates the impact of each condition and heightens it.
OSA and COPD Overlap Syndrome
With COPD, individuals struggle to maintain a healthy balance of carbon dioxide and oxygen in their bloodstream in the daytime. When COPD is combined with OSA as well, this sleep breathing condition kicks in the minute an individual falls asleep, leading to further blood chemistry imbalances.
While each person relies on the consolidated sleep they obtain during the night to maintain well-being and health as well as to recover from certain stresses their bodies go through due to chronic illness, individuals can experience chronic breathing challenges when they suffer from both OSA and COPD.
There have been studies showing a prevalence of 11% to 19% of individuals for OSA in individuals with COPD. Around half of all individuals with COPD experience some difficulty with breathing when they're sleeping, even if they're not struggling with full-blown OSA.
Signs of OSA With COPD
Clinical overlap syndrome consequences are:
Increased exacerbation incidence
Greater rates of mortality compared to individuals with either OSA or COPD alone
Prolonged oxygen desaturation during the nighttime, potentially leading to a pulmonary and systemic blood pressure increase.
Worsened quality of life
Greater mortality incidence at night
Symptoms of COPD and OSA Overlap Syndrome
Breathing can be difficult at times when people are struggling with COPD. It may be even more difficult when they have OSA simultaneously.
OSA and COPD overlap Syndrome increases the likelihood of having:
Pulmonary hypertension: This is a high blood pressure of the lung arteries
Hypercapnia: Excessive carbon dioxide in the blood
Fatigue: A drop in the level of energy and increased sleepiness during the day
Poor-quality sleep: It's a challenge to sleep with COPD. It can be difficult to breathe when lying down and the chest tightens.
Frequent bathroom trips:
Coughing: This can be characterized by a nagging cough upon wakening.
Heart complications: There is a higher risk of a life-threatening heart attack with COPD
Sleep apnea could also increase the likelihood of experiencing the following issues:
Since OSA and COPD can cause heart issues, patients should speak with their physicians about how to manage overlap syndrome effectively.
Mortality of OSA and COPD Overlap Syndrome
Individuals with COPD often have decreased blood oxygen levels all day long, even when they're breathing and alert. After they fall asleep, OSA-related airway obstructions can immensely decrease these already lowered levels.
Depending on the severity, this can be life-threatening. It's essential to understand, while both COPD and OSA are hard to treat and live with, individuals with both have a greater risk for worsened morbidity and early mortality when compared to those who only have one of the conditions and not both.
When independent of each other, these disorders indirectly and directly contribute to tens of thousands of deaths in the U.S. each year. Combined, their adverse effects can be even larger than their effects alone.
Mortality for individuals with OSA and COPD overlap syndrome seem greater than individuals who suffer from just one of the conditions.
One study looking at individuals with OSA revealed that mortality risks increased sevenfold when they struggled with the comorbid condition, COPD. Scientists in a 2010 study covering a nine-year period, studied outcomes data on individuals with COPD vs. those with OSA and COPD overlap syndrome. They found those with overlap syndrome who didn't receive CPAP treatment, had a 42.2% all-cause mortality. On the other hand, for individuals with COPD with no OSA, there was a 24.2% all-cause mortality.