What are the other Names for this Condition? (Also known as/Synonyms)

• Pulmonary Hypertension due to Sleep Disordered Breathing
• Pulmonary Hypertension in Sleep Disordered Breathing
• Pulmonary Hypertension with Sleep Disordered Breathing

What is Pulmonary Hypertension and Sleep Disordered Breathing? (Definition/Background Information)

• Pulmonary Hypertension (PH) is a disorder characterized by very high blood pressure (above normal) in the lungs due to a variety of causes. It should not be confused with systemic hypertension, otherwise known as ‘high blood pressure’
• The pulmonary blood vessels (arteries and veins) are usually a “low pressure” system, which means the blood pressure within the lung blood vessels is much lower than the rest of the body
• This elevated pulmonary blood pressure causes the right side of the heart to work harder, placing an increased burden on the heart. It is often caused by various lung and heart disease but can be associated with many other conditions too
• The World Health Organization (WHO) has clinically classified pulmonary hypertension according to certain groups. Pulmonary Hypertension and Sleep Disordered Breathing forms part of WHO group 3 (sub group 3.4.). WHO group 3 encompasses pulmonary hypertension due to lung disease and/or hypoxia
• Sleep disordered breathing (SDB) constitutes a group of common sleep related conditions that are characterized by disrupted breathing patterns and poor ventilation during sleep. SBD includes the following types:
  • Obstructive sleep apnea (OSA)
  • Central sleep apnea (CSA)
  • Complex sleep apnea
• Pulmonary hypertension is observed in a significant number of individuals with sleep disordered breathing due to pulmonary blood circulation being affected, thus presenting an impaired quality of life in many. It is also reported that many individuals with obstructive sleep apnea present pulmonary arterial hypertension (PAH)
• The signs and symptoms of Pulmonary Hypertension and Sleep Disordered Breathing may include shortness of breath, chest pain, fatigue, and dizziness. The signs and symptoms also depend on the sleep disorder type, but may include poor sleep, depression, increase in weight, and sexual dysfunction
• Following a diagnosis of Pulmonary Hypertension and Sleep Disordered Breathing, the treatment measures may involve the use of medications, such as calcium channel blockers, and bringing about certain lifestyle modifications, among others. Sleep apnea may be treated using positive airway pressure therapy, oral appliance therapy, and surgery
• The prognosis of Pulmonary Hypertension and Sleep Disordered Breathing may be improved if the condition is diagnosed promptly and treated appropriately. However, the overall prognosis depends on several factors including on the severity of the underlying sleep apnea type; it may vary from one individual to another

Who gets Pulmonary Hypertension and Sleep Disordered Breathing? (Age and Sex Distribution)

• The age, gender, and racial/ethnic distribution of Pulmonary Hypertension and Sleep Disordered Breathing depends on the underlying type of sleep apnea causing PH
• A majority of cases are observed in adults, particularly older adults
• Both males and females are affected
• According to some reports:
  • Between 17% to 53% with obstructive sleep apnea show pulmonary hypertension
  • Around 45% of central sleep apnea patients have pulmonary hypertension
  • Over 80% of individuals with pulmonary arterial hypertension had some forms of sleep apnea

• Worldwide, individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Pulmonary Hypertension and Sleep Disordered Breathing? (Predisposing Factors)

The risk factors for Pulmonary Hypertension in Sleep Disordered Breathing are dependent on the respective risk factors of sleep apnea types, and these may include:

• Being obese or overweight
• A family history of sleep apnea
• Hypothyroidism
• Individuals with neurological disorders that include cerebral palsy, myasthenia (an autoimmune disorder), and muscular dystrophy
• Space-occupying masses or tissues (in the head and neck region), such as tonsils or adenoids, in children
• Insufficient muscle tone of the palate, tongue, and pharynx, particularly in children
• A large neck size
• Additional risk factors for obstructive sleep apnea (OSA) include diabetes and skeletal abnormalities that can obstruct one’s ability to breath (such as scoliosis or ankylosing spondylitis)

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Pulmonary Hypertension and Sleep Disordered Breathing? (Etiology)

Pulmonary hypertension is caused by an increased blood pressure within the blood vessels of the lung. Pulmonary Hypertension in Sleep Disordered Breathing is associated with the underlying sleep disordered breathing (sleep apnea) types; it develops secondary to the condition. It is reported that long-term sleep apnea adversely affects the functioning of the cardiovascular system.

• For individuals with obstructive sleep apnea, low blood oxygen levels (hypoxia) result in what is called hypoxic pulmonary vasoconstriction (HPVC)
• Essentially, the lungs try to divert blood toward more well-ventilated/oxygenated areas to increase the amount of oxygen the blood can carry to the rest of the body
• In doing so, constriction of various pulmonary vessels occurs. When this constriction occurs, it results in increased pulmonary vascular pressure
• When this feedback loop becomes a chronic manifestation, vascular remodeling occurs. Vessels thicken and harden to accommodate the increased pressure. This remodeling perpetuates PH

What are the Signs and Symptoms of Pulmonary Hypertension and Sleep Disordered Breathing?

The signs and symptoms of Pulmonary Hypertension and Sleep Disordered Breathing depends on a set of several factors that include age of the individual, overall health of the individual, and associated health conditions. The signs and symptoms can be directly related to pulmonary hypertension, and to the underlying sleep disordered breathing (sleep apnea) type.

The common signs and symptoms of pulmonary hypertension include:

• Progressive shortness of breath (especially while exercising), is the most common symptom
• Fatigue (frequent tiredness)
• Chest pain
• Dizziness and fainting
• Swelling of the ankles/legs
• Palpitations
• Bluish lips and skin, observed during the later stages
• Irregular heartbeat (arrhythmias)
• Fluid in the abdomen (ascites)

The signs and symptoms related to sleep apnea depend on its severity and type, and may include:

• Daytime sleepiness is a common feature with sleep apnea
• Constantly falling asleep while doing other activities such as reading, watching television, or even while driving a vehicle
• Snoring
• Frequent urination during the night
• Morning headaches

Memory or learning problems, feeling irritable, depressed, and mood swings, are other signs and symptoms of the condition.

Often, the detection of the associated condition may help in determining the cause of pulmonary hypertension.

How is Pulmonary Hypertension and Sleep Disordered Breathing Diagnosed?

To diagnose Pulmonary Hypertension and Sleep Disordered Breathing, a diagnosis of pulmonary hypertension (PH) must first be established. This involves certain preliminary diagnostic procedures. Depending on the results of these tests, confirmation will be made with a right-heart catheterization. After a diagnosis of PH is made, the healthcare provider may undertake further tests to diagnose sleep apnea, as required.

The preliminary procedures may include:

• A complete physical examination of the patient 
• A thorough checking of the patient’s medical history and a detailed checking of the family history of the patient
• Blood tests:
  • Blood tests help rule out other diseases
  • They also help in checking the blood oxygen levels
  • The measurement of brain natriuretic peptide (BNP) can be used to assess the strain on one’s heart
• Chest X-ray: Chest X-rays can reveal structural signs of pulmonary hypertension by identifying changes in the pulmonary arteries or enlargement of the right side of the heart
• Electrocardiogram (ECG): An electrocardiogram checks the electrical impulses of the heart. There are certain identifiable patterns on an ECG that may indicate pulmonary hypertension. However, ECG is not specific enough to diagnose the condition by itself, so a combination of tests may be recommended by the healthcare provider
• Echocardiogram: In this procedure, a sonogram of the heart is taken and used to measure overall functioning as well as measure the pressure within the chambers of the right heart. An echocardiogram is also often times used to monitor a patient’s condition after diagnosis and during treatment
• Pulmonary function tests: These tests help measure the quality of breathing and check the functioning of the lungs (such as how much air is breathed in and out, as well as the quality of oxygen exchange)
• Exercise tolerance test (six-minute walk test): This helps to measure the patient’s ability to exercise
• Nuclear scan (ventilation/perfusion scan or V/Q scan): This tool helps identify any new or chronic blood clots in the vessels of the lungs that could be causing pulmonary hypertension

A diagnosis of sleep apnea may additionally involve:

• Study of one’s sleep habits; individuals may be recommended to maintain a ‘sleep diary’, which may help the physician evaluate, if there is a sleep disorder
• Consultation with a sleep medicine expert
• Polysomnography (sleep study)

The gold standard for pulmonary hypertension diagnosis and management is right-heart catheterization and acute vasodilator challenge.

• Right-heart catheterization:
  • If pulmonary hypertension is suspected based off preliminary tests and procedures, a right-heart catheterization test is ordered to help confirm the diagnosis
  • This test can accurately quantify right-heart pressures (measure the pressure within the chambers of the right heart), especially the pressure inside the pulmonary arteries
  • During this procedure, a very small catheter is inserted into a large vein (either within the patient’s groin or neck) and passed into the patient’s heart and vasculature to measure the internal blood pressures 
• Vasodilator study (acute vasodilator challenge):
  • While this test is not used to necessarily “diagnose” pulmonary hypertension, it is used to evaluate the patient for possible therapeutic management
  • Like right-heart catheterization, a catheter is placed within the pulmonary artery to test for vasodilation (or relaxation) in response to a class of medications called calcium channel blockers (CCBs)
  • The response and dosing of CCBs can be evaluated with this procedure

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Pulmonary Hypertension and Sleep Disordered Breathing?

The complications of Pulmonary Hypertension and Sleep Disordered Breathing depends on a set of several factors that include the age of the individual, overall health of the individual, underlying sleep disordered breathing/sleep apnea type, and promptness of diagnosis. 

Following are the possible complications that may arise due to the condition:

• Right-sided heart failure with hepatic congestion (due to deposition of stones in the liver)
• Pedal edema: Swelling of the leg or ankle
• Pleural effusions: Building-up of excess fluid around the lungs
• Worsening dyspnea (shortness of breath) upon exertion

The complications related to sleep apnea may include:

• High blood pressure
• Heart failure and heart attacks
• Impotence
• Depression
• Impaired quality of life: 

How is Pulmonary Hypertension and Sleep Disordered Breathing Treated?

The treatment of Pulmonary Hypertension and Sleep Disordered Breathing depends on a set of several factors that include the severity of the signs and symptoms, age of the individual, and overall health of the individual.

• A treatment of the underlying sleep disordered breathing (sleep apnea) is essential
• The treatment may include the use of behavioral modification:, continuous positive airway pressure (CPAP), oral appliances, and surgery, if necessary

PH associated with sleep disordered breathing is best treated at a medical center with appropriate expertise. Several medical treatments are highlighted below:

• Conventional medical therapies:
  • Calcium channel blockers (CCBs): These are a group of medications that help vasodilate (or relax) the arteries. However, CCBs are only appropriate for patients demonstrating a favorable response to the vasodilator study
  • Inotropic agents: These are medications that assist in the pumping of the heart 
  • Diuretics, salt limitation, and weight monitoring may be recommended, to limit excess strain on the heart
  • Supplemental oxygen may help an individual meet the ‘oxygen needs’ for normal daily activities
  • Blood thinners: These medications help prevent blood clots, especially in the lung blood vessels
  • Treating underlying diseases or conditions
• Oral, inhaled, subcutaneous, or intravenous treatment options:
  • Endothelin receptor antagonists (ERAs) help in preventing pulmonary blood vessels from narrowing which helps keep the pressures towards normal levels
  • Phosphodiesterase inhibitors (PDE 5 Inhibitors), prostacyclin analogues, and soluble guanylate cyclase (sGC) stimulators, all aid in allowing vessels of the lungs to vasodilate (or relax)
• Additional treatment options may include:
  • Lifestyle modifications, such as nutrition, exercise, avoiding tobacco, and limiting alcohol consumption, are beneficial
  • Judicious exercising may be effective in limiting deconditioning (by building stamina), improving the quality of life, and exercising capacities. Isometric exercises, such as heavy weightlifting, should be avoided
  • Other treatments, depending on the etiology (cause) of pulmonary hypertension, may include various cardiothoracic procedures
  • Lung transplantation may be required with advanced forms of the disorder

How can Pulmonary Hypertension and Sleep Disordered Breathing be Prevented?

Pulmonary Hypertension and Sleep Disordered Breathing may be prevented or controlled if appropriate treatment of the underlying sleep disordered breathing is considered. It may not possible to prevent the development of the sleep condition, in some cases. However, certain measures may be taken to minimize the risk for the same that include:

• Weight-loss in individuals, who are overweight or obese
• Sleeping in a non-supine position (e.g. lateral recumbent) may correct or improve obstructive sleep apnea
• In some cases, the use of a cervical pillow may help
• Individuals are advised to maintain regular sleep hours and avoid alcohol, sedatives, sleeping pills, before bedtime, because they tend to relax the muscles of the throat

The non-modifiable risk factors for pulmonary hypertension (PH), such as age, gender, and genetics (family history), cannot be controlled; and therefore, it may not be possible to prevent PH that develops from these factors. However, an early and effective treatment is critical and imperative.

• For those with a pre-existing condition that is a risk factor for pulmonary hypertension, seeking medical attention at the onset of symptoms may help avoid worsening of the condition and complications 
• Avoidance of recreational drugs, various toxic agents, and inappropriate weight loss drugs is important

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis Pulmonary Hypertension and Sleep Disordered Breathing? (Outcomes/Resolutions)

The prognosis of Pulmonary Hypertension and Sleep Disordered Breathing differs from one individual to another, depending on its severity and on the underlying type of sleep disordered breathing/sleep apnea. It is reported that individuals with obstructive sleep apnea with pulmonary hypertension may have a reduced quality of life.

Additional and Relevant Useful Information for Pulmonary Hypertension and Sleep Disordered Breathing:

The following DoveMed website links are useful resources for additional information:

https://www.dovemed.com/diseases-conditions/sleep-apnea/

https://www.dovemed.com/diseases-conditions/apnea-of-prematurity-aop/

https://www.dovemed.com/diseases-conditions/rem-sleep-behavior-disorder/