Hypersomnolence Disorders — MCQs
A 40-year-old man presents with daytime sleepiness and impaired concentration and memory. On examination his BMI is 41 kg/m2, BP is 160/100 mm Hg. His awake ABG analysis is given: PaO2=66 mm Hg, PaCO2=50 mm Hg, HCO3=28 mEq/L. What is the most likely diagnosis?
A 32-year-old man comes to the physician complaining of excessive sleepiness for the past several months. He reports falling asleep while dealing with customers and had a near accident when he fell asleep while driving. The patient reports that he occasionally hears voices while falling asleep and finds himself "temporarily frozen" and unable to move upon awakening. Which of the following is the most appropriate treatment for this patient?
Narcolepsy is associated with?
Kleine-Levin syndrome is associated with:
A 7-year-old girl is reported by the parents as waking up in the night screaming, and she sits up in bed frightened. She does not respond to questions and after 2 or 3 minutes she goes back to sleep. She has no memory of these events the following morning. Which of the following is the most likely diagnosis?
What is the primary characteristic feature of Klein-Levin syndrome?
Which of the following statements about narcolepsy is false?
Which of the following statements about narcolepsy is false?
Which one of the following factors is the most significant as a risk factor for post-partum psychosis?
Bruxism most commonly occurs during which phase of sleep?
Hypersomnolence Disorders Indian Medical PG Practice Questions and MCQs
Question 1: A 40-year-old man presents with daytime sleepiness and impaired concentration and memory. On examination his BMI is 41 kg/m2, BP is 160/100 mm Hg. His awake ABG analysis is given: PaO2=66 mm Hg, PaCO2=50 mm Hg, HCO3=28 mEq/L. What is the most likely diagnosis?
- A. Obstructive sleep apnea (Correct Answer)
- B. Narcolepsy
- C. Obesity hypoventilation syndrome
- D. Central sleep apnea
Explanation: ***Obstructive Sleep Apnea (Correct Answer)*** - Classic triad: **morbid obesity (BMI 41 kg/m²)**, **excessive daytime somnolence**, and **systemic hypertension (160/100 mmHg)** — hallmarks of OSA - **ABG findings** (PaO2=66 mmHg, PaCO2=50 mmHg, HCO3=28 mEq/L) indicate **chronic nocturnal hypoxemia and hypercapnia** with compensatory **metabolic alkalosis** from repeated apneic episodes - **Cognitive impairment** (impaired concentration and memory) results from **sleep fragmentation** and intermittent nocturnal hypoxia - Obesity promotes **pharyngeal fat deposition** → upper airway narrowing and collapse during sleep → recurrent obstructive events *Narcolepsy* - Causes excessive daytime sleepiness but is **not associated with obesity, hypertension, or ABG abnormalities** - Hallmarks include **cataplexy**, sleep paralysis, and hypnagogic/hypnopompic hallucinations — none present here - Caused by **orexin (hypocretin) deficiency**; associated with **HLA-DQB1*06:02**; ABG is normal *Obesity Hypoventilation Syndrome (OHS / Pickwickian Syndrome)* - Defined as **awake PaCO2 >45 mmHg + BMI >30 kg/m²** with exclusion of other causes of hypoventilation - OHS frequently coexists as an **overlap with and consequence of severe OSA** rather than being the primary diagnosis - In this setting, **OSA is the most prevalent and primary diagnosis**; OHS is specifically considered when awake hypoventilation persists despite adequate OSA treatment *Central Sleep Apnea* - Results from **failure of central respiratory drive** (brainstem), not upper airway obstruction - Associated with **congestive heart failure, opioid use, high-altitude exposure, or neurological disease** — none present here - Not characteristically associated with morbid obesity; clinical and ABG picture here favors an **obstructive** rather than central pattern
Question 2: A 32-year-old man comes to the physician complaining of excessive sleepiness for the past several months. He reports falling asleep while dealing with customers and had a near accident when he fell asleep while driving. The patient reports that he occasionally hears voices while falling asleep and finds himself "temporarily frozen" and unable to move upon awakening. Which of the following is the most appropriate treatment for this patient?
- A. Melatonin
- B. Modafinil (Correct Answer)
- C. Clonazepam
- D. Continuous positive airway pressure
Explanation: ***Modafinil*** - The patient's symptoms of **excessive daytime sleepiness** (EDS), **hypnagogic hallucinations** (hearing voices while falling asleep), and **sleep paralysis** are classic signs of **narcolepsy**. - **Modafinil** is a **non-amphetamine stimulant** that promotes wakefulness and is a first-line treatment for narcolepsy, improving alertness and reducing EDS. *Melatonin* - **Melatonin** is a hormone involved in regulating the **sleep-wake cycle** and is primarily used for **insomnia**, **jet lag**, or **circadian rhythm disorders**. - It is not effective for treating the hallmark symptoms of narcolepsy, such as cataplexy or excessive daytime sleepiness. *Clonazepam* - **Clonazepam** is a **benzodiazepine** that acts as a central nervous system depressant, primarily used for **anxiety disorders**, seizures, and some sleep disorders like **REM sleep behavior disorder**. - While it can help with some parasomnias, it would worsen daytime sleepiness in a patient with narcolepsy and is not a primary treatment for its core symptoms. *Continuous positive airway pressure* - **Continuous positive airway pressure (CPAP)** is the standard treatment for **obstructive sleep apnea (OSA)**, a condition characterized by recurrent upper airway collapse during sleep. - Although OSA can cause excessive daytime sleepiness, the patient's additional symptoms of hypnagogic hallucinations and sleep paralysis are not typical of OSA, making narcolepsy and its specific treatments more appropriate.
Question 3: Narcolepsy is associated with?
- A. Late age of onset
- B. Hypnagogic hallucination (Correct Answer)
- C. Decreased NREM sleep
- D. Normal sleep architecture
Explanation: ***Hypnagogic hallucination*** - **Hypnagogic hallucinations** are vivid, dream-like perceptual experiences occurring at **sleep onset** and are one of the **classic tetrad features** of narcolepsy. - They occur in **30-60% of narcolepsy patients** and result from the intrusion of **REM sleep phenomena** into the transition from wakefulness to sleep. - These hallucinations reflect the **REM sleep dysregulation** that is central to narcolepsy pathophysiology. - Other tetrad features include **excessive daytime sleepiness, cataplexy, and sleep paralysis**. *Late age of onset* - Narcolepsy typically has an **early age of onset**, most commonly between **10-25 years** (adolescence and young adulthood). - Peak onset is around **15 years of age**. - Late-onset narcolepsy is uncommon and may suggest secondary causes. *Normal sleep architecture* - Narcolepsy is characterized by **disrupted sleep architecture**, not normal architecture. - Key abnormalities include **sleep-onset REM periods (SOREMPs)**, where patients enter REM sleep within **15 minutes** of sleep onset, bypassing normal NREM stages. - Nocturnal sleep is **fragmented** with frequent awakenings. *Decreased NREM sleep* - While narcolepsy involves **REM sleep dysregulation** with premature REM entry, characterizing it simply as "decreased NREM sleep" is not the standard clinical description. - The primary pathology is **abnormal REM sleep timing and distribution**, including SOREMPs during daytime naps and nighttime sleep. - The focus is on **REM sleep intrusion** rather than NREM reduction per se.
Question 4: Kleine-Levin syndrome is associated with:
- A. Depression
- B. Anxiety
- C. Hypersomnia (Correct Answer)
- D. Chronic insomnia
Explanation: ***Hypersomnia*** - **Kleine-Levin syndrome** is characterized by recurrent episodes of **hypersomnia**, meaning excessive sleepiness. - Patients can sleep for 16 to 20 hours a day during these episodes, which may last for days or weeks. *Depression* - While mood disturbances can occur, **Kleine-Levin syndrome** primarily involves sleep and behavioral changes, not core symptoms of **depression**. - **Depression** is typically characterized by persistent low mood, anhedonia, and other symptoms, rather than episodic hypersomnia alone. *Anxiety* - **Anxiety** is not a primary symptom or defining characteristic of **Kleine-Levin syndrome**. - Patients may experience frustration or irritability due to their condition, but generalized anxiety is not a core feature. *Chronic insomnia* - **Chronic insomnia**, which is difficulty falling or staying asleep, is actually the opposite of the key symptom in **Kleine-Levin syndrome**. - The hallmark of Kleine-Levin syndrome is **excessive sleepiness (hypersomnia)**, not difficulty sleeping.
Question 5: A 7-year-old girl is reported by the parents as waking up in the night screaming, and she sits up in bed frightened. She does not respond to questions and after 2 or 3 minutes she goes back to sleep. She has no memory of these events the following morning. Which of the following is the most likely diagnosis?
- A. Nightmare
- B. Sleep terrors (Correct Answer)
- C. Narcolepsy
- D. Nocturnal seizures
Explanation: ***Sleep terrors*** - **Sleep terrors** are characterized by abrupt awakenings, intense fear and screaming, autonomic arousal, and unresponsiveness, typically occurring during **NREM sleep** in the first third of the night. - The child will have **no memory** of the event the next morning, which is a key diagnostic feature, and they often return to sleep quickly afterward. *Nightmare* - **Nightmares** occur during **REM sleep**, usually in the latter half of the night, and the individual can often recall vivid and frightening details upon waking. - Unlike sleep terrors, individuals experiencing nightmares are typically **responsive to comfort** and fully alert after waking. *Narcolepsy* - **Narcolepsy** is a chronic neurological condition characterized by overwhelming daytime sleepiness and irresistible urges to sleep, often accompanied by **cataplexy**. - It does not involve nocturnal screaming episodes or unresponsiveness followed by a quick return to sleep with no memory. *Nocturnal seizures* - **Nocturnal seizures** can cause nocturnal awakenings with confusion or unusual behaviors, but they often involve **stereotyped movements**, sometimes with motor manifestations or post-ictal confusion that lasts longer than a few minutes. - While there might be no memory of the event, the screaming and frightened demeanor without typical seizure activity make sleep terrors a more likely diagnosis.
Question 6: What is the primary characteristic feature of Klein-Levin syndrome?
- A. Insomnia
- B. Anxiety
- C. Depression
- D. Hypersomnia (Correct Answer)
Explanation: ***Hypersomnia*** - **Hypersomnia** is the cardinal and primary characteristic feature of Klein-Levin syndrome, characterized by recurrent episodes of excessive sleepiness lasting days to weeks. - During these episodes, individuals may sleep for **16 to 20 hours a day** and are extremely difficult to awaken. - Episodes are often accompanied by **cognitive disturbances** (confusion, derealization), **behavioral changes** (apathy, hyperphagia, hypersexuality), but **hypersomnia remains the defining feature**. - Normal functioning returns between episodes. *Insomnia* - **Insomnia** (difficulty falling or staying asleep) is the opposite of the key symptom seen in Klein-Levin syndrome. - Klein-Levin syndrome is a disorder of excessive sleep, not sleep deprivation. *Anxiety* - **Anxiety** may occur as a secondary feature or during the distress of episodes, but it is not the primary characteristic feature. - The core pathology manifests as profound sleep disturbance, not an anxiety disorder. *Depression* - **Depression** is sometimes observed during or after episodes of Klein-Levin syndrome, but it is not the primary defining feature. - The diagnostic hallmark is the **recurrent hypersomnia with associated cognitive and behavioral symptoms**, not mood disturbance.
Question 7: Which of the following statements about narcolepsy is false?
- A. Loss of muscle tone
- B. Hallucination
- C. Cataplexy
- D. Sleep architecture normal (Correct Answer)
Explanation: ***Sleep architecture normal*** ✓ **This is the FALSE statement** - Narcolepsy is characterized by **abnormal sleep architecture**, specifically an **abbreviated latency to REM sleep** (often <15 minutes, compared to normal 90 minutes). - Patients experience **fragmented nighttime sleep** with frequent awakenings and difficulty maintaining continuous sleep. - Sleep studies show **disrupted sleep-wake cycles** and **premature entry into REM sleep**. *Loss of muscle tone* - TRUE statement - **Loss of muscle tone** is the defining feature of **cataplexy**, a hallmark symptom of narcolepsy type 1. - Sudden emotional triggers (laughter, surprise, anger) lead to muscle weakness or paralysis without loss of consciousness. - This reflects neurological dysfunction affecting muscle control regulation during wakefulness. *Hallucination* - TRUE statement - **Hypnagogic hallucinations** (upon falling asleep) and **hypnopompic hallucinations** (upon waking) are common in narcolepsy. - These vivid, dream-like experiences occur during sleep-wake transitions due to intrusion of REM sleep phenomena into wakefulness. - Can involve visual, auditory, or tactile sensations. *Cataplexy* - TRUE statement - **Cataplexy** is a hallmark symptom of **narcolepsy type 1** (narcolepsy with cataplexy). - Involves sudden, brief episodes of bilateral muscle weakness or paralysis triggered by strong emotions. - Results from loss of hypocretin (orexin) neurons in the hypothalamus.
Question 8: Which of the following statements about narcolepsy is false?
- A. Day dreaming (Correct Answer)
- B. Cataplexy
- C. Sudden sleep and decreased REM latency
- D. Hypnagogic hallucinations
Explanation: ***Day dreaming*** - While people with narcolepsy experience excessive daytime sleepiness, **daydreaming** is a normal cognitive process and not a characteristic symptom of narcolepsy. - Narcolepsy involves **irresistible urges to sleep** or sudden sleep attacks, which are distinct from simply daydreaming. *Hypnagogic hallucinations* - These are **vivid, often frightening hallucinations** that occur as a person is falling asleep. - They are a common symptom of narcolepsy, along with hypnopompic hallucinations (occurring upon waking). *Cataplexy* - **Cataplexy** is a sudden, brief loss of voluntary muscle tone, often triggered by strong emotions like laughter or anger. - It is a hallmark symptom of **Type 1 narcolepsy** and is caused by the intrusion of REM sleep atonia into wakefulness. *Sudden sleep and decreased REM latency* - Individuals with narcolepsy experience **sudden and irresistible sleep attacks** during the day. - They also have **decreased REM latency**, meaning they enter REM sleep much faster than usual, often within minutes of falling asleep.
Question 9: Which one of the following factors is the most significant as a risk factor for post-partum psychosis?
- A. History of post-partum psychosis (Correct Answer)
- B. Primiparity
- C. Undesired pregnancy
- D. Unmarried status
Explanation: ***History of post-partum psychosis*** - A **prior episode of postpartum psychosis** is the strongest risk factor for recurrence, with recurrence rates estimated to be as high as 50-70%. - This indicates a heightened **biological vulnerability** to the hormonal and psychosocial stresses of the postpartum period. *Primiparity* - While primiparity can be associated with increased stress, it is a **less significant risk factor** for postpartum psychosis compared to a history of the condition. - The stress of a first pregnancy and childbirth can contribute to other perinatal mood disorders, but does not carry the same high recurrence risk as previous psychosis. *Undesired pregnancy* - An undesired pregnancy is often associated with **increased maternal stress, anxiety, and depression**, but it is generally a **weaker predictor** of postpartum psychosis than a personal history of the disorder. - While it can complicate the perinatal period, it doesn't confer the same high risk for a severe psychotic episode. *Unmarried status* - Unmarried status may increase the risk of **postpartum depression** due to lack of social support or increased stress, but it is **not a primary risk factor** for postpartum psychosis itself. - The familial and social support systems are important for overall well-being, but a previous psychotic episode is a much stronger predictor.
Question 10: Bruxism most commonly occurs during which phase of sleep?
- A. REM sleep
- B. NREM Stage I
- C. NREM Stage II (Correct Answer)
- D. NREM Stage III
Explanation: **Explanation:** **Sleep Bruxism** is a sleep-related movement disorder characterized by the involuntary grinding or clenching of teeth. **Why NREM Stage II is correct:** While bruxism can occur in any stage of sleep, it is most frequently observed during **NREM Stage II (Light Sleep)**. Statistically, about 80% of bruxism episodes occur during NREM sleep, with the vast majority clustered in Stage II. These episodes are often associated with "micro-arousals"—brief shifts in sleep depth where the sympathetic nervous system activity increases, leading to rhythmic masticatory muscle activity (RMMA). **Analysis of Incorrect Options:** * **REM Sleep (A):** Although bruxism can occur during REM, it is less common. REM-related bruxism is often associated with more severe clinical symptoms and may be linked to obstructive sleep apnea. * **NREM Stage I (B):** This is a transitional phase of very light sleep. While grinding can occur here, the frequency is significantly lower than in Stage II. * **NREM Stage III (D):** Also known as Slow Wave Sleep (SWS) or deep sleep. Parasomnias like sleepwalking (somnambulism) and night terrors typically occur here, but bruxism is less frequent in this stage compared to Stage II. **High-Yield Clinical Pearls for NEET-PG:** * **Treatment of Choice:** The first-line management is usually **stress reduction** and **dental guards (occlusal splints)** to prevent tooth wear. * **Pharmacotherapy:** If severe, **Benzodiazepines** (like Clonazepam) or muscle relaxants may be used short-term. * **Association:** Bruxism is frequently associated with stress, anxiety, and other sleep disorders like Obstructive Sleep Apnea (OSA). * **Key Distinction:** Do not confuse bruxism (Stage II) with **Sleep Terrors/Somnambulism**, which are classic **Stage III (N3)** phenomena.
Want unlimited practice?
Get full access to all questions, explanations, and performance tracking.
Start For Free