Which is not true of obstructive sleep apnea?
**Obstructive Sleep Apnea (OSA)**
**Core Concept**
Obstructive sleep apnea is a sleep disorder characterized by repeated episodes of partial or complete upper airway obstruction during sleep, leading to intermittent hypoxia, sleep fragmentation, and daytime hyperosmnolence. This condition is often associated with obesity, hypertension, and cardiovascular disease.
**Why the Correct Answer is Right**
Obstructive sleep apnea is primarily caused by the collapse of the pharyngeal airway during sleep, which can be due to a combination of factors such as obesity, craniofacial abnormalities, and neuromuscular dysfunction. The repeated episodes of hypoxia and sleep fragmentation can lead to increased sympathetic tone, oxidative stress, and inflammation, which contribute to the development of cardiovascular disease and other comorbidities. The diagnosis of OSA is typically made using polysomnography (PSG) or home sleep apnea testing (HSAT).
**Why Each Wrong Option is Incorrect**
* **Option A:** This statement is not true of obstructive sleep apnea. OSA is indeed characterized by repeated episodes of partial or complete upper airway obstruction during sleep, leading to intermittent hypoxia and sleep fragmentation.
* **Option B:** This statement is not true of obstructive sleep apnea. OSA is primarily caused by the collapse of the pharyngeal airway during sleep, which can be due to a combination of factors such as obesity, craniofacial abnormalities, and neuromuscular dysfunction.
* **Option C:** This statement is not true of obstructive sleep apnea. OSA is indeed associated with an increased risk of cardiovascular disease, including hypertension, myocardial infarction, and stroke.
* **Option D:** This statement is not true of obstructive sleep apnea. OSA is primarily caused by the collapse of the pharyngeal airway during sleep, which can be due to a combination of factors such as obesity, craniofacial abnormalities, and neuromuscular dysfunction.
**Clinical Pearl / High-Yield Fact**
A key clinical correlation to remember is that OSA is often associated with other sleep disorders, such as restless leg syndrome and insomnia. Additionally, the diagnosis of OSA can be challenging, and a high index of suspicion is necessary, particularly in patients with a history of snoring, daytime hyperosmnolence, and other comorbidities.
**Correct Answer: B.**