# Clinical Cases: Sleep Medicine ## Case 1: Obstructive Sleep Apnea with Cardiovascular Risk ### Patient Presentation **Demographics:** 52-year-old male construction foreman **Chief Complaint:** "My wife says I stop breathing at night and she's scared I'm going to die in my sleep. I'm also falling asleep at work." **History of Present Illness:** The patient presents to the sleep medicine clinic at the insistence of his wife, who has witnessed increasingly frequent and prolonged episodes of breathing cessation during sleep over the past 2-3 years. She describes loud, crescendo snoring punctuated by periods of silence lasting 20-30 seconds, followed by a choking or gasping sound and resumption of breathing. She estimates these episodes occur dozens of times per hour and reports that she has moved to a separate bedroom because of the noise. The patient acknowledges loud snoring dating back at least 10 years but has only recently noticed daytime symptoms. He reports excessive daytime sleepiness, particularly in sedentary situations: he frequently falls asleep watching television, during meetings, and as a passenger in a vehicle. More concerning, he reports two recent near-miss incidents while driving to construction sites, where he "nodded off" briefly at the wheel. He wakes feeling unrefreshed despite 7-8 hours of time in bed and describes morning headaches 3-4 times per week that resolve within an hour of awakening. He endorses nocturia (2-3 times nightly) and reports decreased libido over the past year. His wife also notes that he has become more irritable and forgetful. He has gained approximately 15 kg over the past 5 years. His primary care physician recently found his blood pressure to be persistently elevated despite two antihypertensive medications and referred him for sleep evaluation. **Past Medical History:** - Resistant hypertension (BP poorly controlled on two medications) - Type 2 diabetes mellitus (diagnosed 4 years ago, HbA1c 7.9%) - Hyperlipidemia - Obesity (BMI 36.8) - Gastroesophageal reflux disease (GERD) - Atrial fibrillation — new diagnosis on recent routine ECG (paroxysmal) - No prior sleep study **Medications:** - Amlodipine 10 mg daily - Losartan 100 mg daily - Metformin 1000 mg twice daily - Atorvastatin 40 mg daily - Omeprazole 20 mg daily - Apixaban 5 mg twice daily (started recently for atrial fibrillation) - Aspirin 81 mg daily **Social History:** - Construction foreman — heavy machinery exposure, early morning starts (5:00 AM) - Married, two adult children - Former smoker (quit 5 years ago; 25-pack-year history) - Alcohol: 2-3 beers most evenings, more on weekends - Diet: high-carbohydrate, large portions; frequently eats late evening meals - Minimal exercise; previously active in construction labor but now primarily supervisory - Sleeps supine; wife reports that snoring and apneas are worse in this position **Family History:** - Father: died of stroke at age 62; was a heavy snorer with obesity - Mother: hypertension, type 2 diabetes, alive at age 78 - Brother: diagnosed with sleep apnea at age 48, uses CPAP ### Physical Examination - **Vital Signs:** BP 158/96 mmHg (despite two antihypertensives), HR 84 bpm (irregular), RR 16/min, Temp 36.7°C, Weight 118 kg, Height 179 cm, BMI 36.8 kg/m², Neck circumference 46 cm (18 inches), Waist circumference 112 cm - **General:** Obese male; plethoric facies; appears fatigued; falls asleep briefly during history-taking - **Epworth Sleepiness Scale (ESS):** Score 17/24 (severe excessive daytime sleepiness; >10 is abnormal) - **STOP-BANG Score:** 7/8 (high risk for OSA) - Snoring: Yes | Tired: Yes | Observed apneas: Yes | Pressure (HTN): Yes - BMI >35: Yes | Age >50: Yes | Neck >40 cm: Yes | Gender male: Yes - **HEENT:** - Mallampati class IV (only hard palate visible; soft palate, uvula, and tonsillar pillars not visible) - Crowded oropharynx with redundant pharyngeal tissue - Large tongue (macroglossia) - Retrognathia (recessed mandible) - No nasal septal deviation; mild nasal congestion - **Neck:** Thick neck with excess adipose tissue; no thyromegaly; no lymphadenopathy; neck circumference 46 cm - **Cardiovascular:** Irregularly irregular rhythm (consistent with atrial fibrillation); no murmurs; mild bilateral pedal edema (1+) - **Respiratory:** Clear to auscultation; no wheeze; adequate air movement; SpO2 94% on room air awake - **Abdomen:** Obese, non-tender; central adiposity - **Extremities:** 1+ bilateral pedal edema; no cyanosis ### Workup and Results **Laboratory Studies:** | Test | Result | Reference Range | |------|--------|-----------------| | HbA1c | 7.9% | <7.0% (diabetic goal) | | Fasting glucose | 162 mg/dL | 70-100 mg/dL | | TSH | 2.8 mIU/L | 0.5-4.5 mIU/L | | Free T4 | 1.2 ng/dL | 0.8-1.8 ng/dL | | BMP | Within normal limits | -- | | CBC | Hgb 17.2 g/dL, Hct 52% | 13.5-17.5 g/dL; 38.3-48.6% (**polycythemia — chronic hypoxemia**) | | BNP | 180 pg/mL | <100 pg/mL (**mildly elevated**) | | Total cholesterol | 218 mg/dL | <200 mg/dL | | LDL | 132 mg/dL | <100 mg/dL | | Triglycerides | 220 mg/dL | <150 mg/dL | | Testosterone (total, AM) | 228 ng/dL | 300-1000 ng/dL (**low**) | **Imaging/Additional Studies:** - **In-laboratory polysomnography (PSG) — diagnostic study results:** - Total recording time: 462 minutes; Total sleep time: 385 minutes; Sleep efficiency: 83% - Sleep latency: 4 minutes (shortened — consistent with excessive sleepiness) - REM latency: 68 minutes (normal) - Sleep architecture: Increased N1 (28%), decreased N3 (8%), decreased REM (14%); frequent arousals and sleep fragmentation - **Apnea-Hypopnea Index (AHI): 68 events/hour** (Severe OSA; mild 5-15, moderate 15-30, severe >30) - Obstructive apneas: 312; Obstructive hypopneas: 124; Central apneas: 8; Mixed apneas: 12 - **Oxygen desaturation index (ODI):** 62 events/hour - **Minimum SpO2:** 68% (severe desaturation; sustained SpO2 <90% for 42% of total sleep time) - **Mean SpO2 during sleep:** 87% - Apneas and desaturations significantly worse in REM sleep (AHI-REM: 92/hour) and in the supine position (AHI-supine: 84/hour) - Snoring: present >80% of recording time - No significant periodic limb movements (PLMI <5/hour) - **ECG during PSG:** Intermittent atrial fibrillation; cyclical heart rate variation with bradycardia during apneas (nadir 42 bpm) and tachycardia post-arousal (peak 118 bpm) - **Echocardiogram:** Mild left ventricular hypertrophy; left atrial dilation (4.6 cm); LVEF 50% (low-normal); mild tricuspid regurgitation with estimated RVSP 38 mmHg (borderline elevated, suggesting early pulmonary hypertension) - **ECG (resting):** Atrial fibrillation with controlled ventricular rate; left ventricular hypertrophy by voltage criteria ### Clinical Image ![Polysomnography tracing showing obstructive sleep apnea events with oxygen desaturation](case_01_image.jpg) *Representative polysomnography tracing illustrating obstructive apneic events with cyclical oxygen desaturation, arousal responses, and associated cardiac rhythm changes in severe obstructive sleep apnea. Source: Educational illustration.* ### Diagnosis **Severe Obstructive Sleep Apnea (AHI 68/hour) with Cardiovascular Comorbidities** **Key Diagnostic Criteria:** - AHI of 68 events/hour on diagnostic polysomnography (severe OSA: AHI >30) - Severe nocturnal hypoxemia (nadir SpO2 68%, >42% of sleep time below 90%) - Classic symptomatology: witnessed apneas, excessive daytime sleepiness (ESS 17), morning headaches, nocturia - STOP-BANG score 7/8 (very high risk) - Anatomic risk factors: obesity (BMI 36.8), neck circumference 46 cm, Mallampati IV, retrognathia, macroglossia - Associated cardiovascular complications: resistant hypertension, paroxysmal atrial fibrillation, left ventricular hypertrophy, early pulmonary hypertension, polycythemia (secondary to chronic intermittent hypoxemia) ### Treatment Plan 1. **Continuous Positive Airway Pressure (CPAP) — first-line therapy:** - In-laboratory CPAP titration study to determine optimal pressure (alternative: auto-titrating CPAP/APAP with pressure range 6-16 cmH2O) - Mask fitting session: trial nasal mask, nasal pillows, and full-face mask to optimize comfort and minimize leak (full-face may be needed if significant mouth breathing) - Heated humidification to reduce nasal dryness and improve comfort - Target: AHI <5 events/hour on treatment; SpO2 >90% throughout the night - **Adherence support:** Sleep technologist education, scheduled 2-week and 1-month follow-up calls; download CPAP data at each visit. Medicare adherence requirement: >4 hours/night on >70% of nights in the first 90 days - Expected benefits: reduction in blood pressure (average 5-10 mmHg drop), improved atrial fibrillation control, improved daytime alertness, improved glycemic control 2. **Behavioral and lifestyle modifications:** - Weight loss: target 10% body weight reduction (12 kg); referral to structured weight management program; consider GLP-1 receptor agonist (semaglutide) which would also address diabetes and has shown independent benefit in OSA - Positional therapy: avoid supine sleeping; consider a positional therapy device (e.g., Night Shift) given significant positional component (AHI-supine 84 vs non-supine estimated ~45) - Alcohol cessation or significant reduction: alcohol relaxes upper airway muscles and worsens OSA severity; avoid all alcohol within 4 hours of bedtime - Avoid sedating medications (benzodiazepines, opioids, antihistamines) - Regular exercise program: even without weight loss, exercise reduces AHI by approximately 25% 3. **Cardiovascular risk management (coordinate with cardiology and primary care):** - Blood pressure: CPAP therapy often allows reduction or improved control of antihypertensives; expect improvement within 1-3 months - Atrial fibrillation: CPAP adherence reduces AF recurrence by 42%; essential before any consideration of cardioversion or ablation - Optimize statin therapy: increase atorvastatin to 80 mg given elevated LDL and high cardiovascular risk - Testosterone: re-evaluate after 3-6 months of CPAP therapy (OSA treatment often improves testosterone levels; testosterone supplementation may worsen OSA) - BNP elevation: monitor; likely reflects diastolic dysfunction and pulmonary hypertension from OSA 4. **Occupational safety:** - Driving restriction discussion: patient should not drive until excessive daytime sleepiness is adequately treated (ESS <10, no near-miss events); report requirements vary by jurisdiction - Heavy machinery operation restriction until CPAP adherence demonstrated and sleepiness resolved - Provide documentation for employer if accommodations needed 5. **Follow-up schedule:** - CPAP titration PSG within 2 weeks - Clinic visit at 1 month with CPAP data download - Clinic visits at 3, 6, and 12 months; then annually - Repeat echocardiogram in 6-12 months to reassess pulmonary pressures and cardiac function - Repeat sleep study if symptoms recur or after significant weight change ### Key Learning Points - Obstructive sleep apnea is an independent risk factor for hypertension, atrial fibrillation, heart failure, stroke, and sudden cardiac death; OSA should be suspected in any patient with resistant hypertension (uncontrolled on 3+ medications) as it is the most common identifiable cause. - The STOP-BANG questionnaire is the most validated screening tool for OSA (sensitivity >90% for moderate-severe OSA when score >=3); it should be used routinely in preoperative evaluations and in patients with cardiovascular risk factors. - CPAP adherence is the greatest challenge in OSA management — approximately 50% of patients are non-adherent at 1 year; early follow-up (within 1-2 weeks), mask comfort optimization, heated humidification, and addressing side effects (nasal dryness, claustrophobia, aerophagia) are critical for long-term success. - Secondary polycythemia (elevated hemoglobin/hematocrit) in OSA results from chronic intermittent hypoxemia stimulating erythropoietin production and is an indicator of disease severity; it typically resolves with effective CPAP therapy. - OSA and metabolic syndrome share a bidirectional relationship: obesity worsens OSA, and untreated OSA promotes weight gain through sleep fragmentation-induced hormonal changes (increased ghrelin, decreased leptin, insulin resistance); GLP-1 receptor agonists represent a promising dual-target intervention. --- ## Case 2: Narcolepsy Type 1 ### Patient Presentation **Demographics:** 19-year-old male college freshman, pre-engineering major **Chief Complaint:** "I keep falling asleep in class no matter how much sleep I get, and sometimes my legs buckle when I laugh really hard." **History of Present Illness:** The patient is a college freshman who presents to the student health sleep clinic with a 3-year history of excessive daytime sleepiness that has significantly worsened since starting college. He reports irresistible sleep attacks occurring 3-5 times daily, lasting 10-20 minutes, after which he briefly feels refreshed. These episodes occur in class, during meals, in conversations, and even while standing. He reports sleeping 8-9 hours per night and yet wakes feeling unrefreshed. His most concerning symptom, which he describes with embarrassment, is sudden episodes of bilateral knee buckling and jaw dropping that occur exclusively during strong positive emotions — typically when laughing hard with friends, hearing a good joke, or feeling surprised. These episodes last 5-30 seconds, during which he is fully conscious but unable to move or speak. He has fallen to the ground completely three times in the past year. He does not lose consciousness during these episodes. His roommate initially thought he was "faking it" or "goofing around." He also reports vivid, often frightening hallucinations as he is falling asleep (hypnagogic), including seeing shadowy figures in his room, hearing his name called, and feeling a presence on his chest. On several occasions, he has awakened from sleep completely unable to move for 1-2 minutes despite being fully aware of his surroundings (sleep paralysis), which he finds terrifying. He also reports disrupted nighttime sleep with frequent awakenings (3-4 times per night) and vivid dreams. His symptoms began around age 16, initially with excessive sleepiness that was attributed to typical teenage sleep patterns, growth, and academic stress. The cataplexy episodes began approximately 6 months later but were initially mild (facial muscle twitching when laughing) and were not recognized. He reports that his symptoms led to significant academic decline in high school and social withdrawal. He was evaluated by his pediatrician at age 17, who diagnosed "possible depression" and started sertraline, which provided no improvement in sleepiness. **Past Medical History:** - No significant medical history - Influenza-like illness at age 15 with prolonged fatigue (in retrospect, possible onset trigger) - No history of head trauma - H1N1 influenza vaccination at age 9 (Pandemrix — the adjuvanted H1N1 vaccine associated with narcolepsy in epidemiological studies was NOT used in the US; he received the standard US-approved vaccine) - Depression diagnosis at age 17 (likely secondary to undiagnosed narcolepsy) - No allergies **Medications:** - Sertraline 50 mg daily (started at age 17 for "depression") - No stimulant medications previously prescribed - Energy drinks: 2-3 per day (reports minimal benefit) **Social History:** - College freshman, pre-engineering major; academic probation due to falling asleep in class and missing assignments - Lives in a dorm with a roommate - Denies alcohol, tobacco, or recreational drug use - Single; reports social isolation due to embarrassment about cataplexy episodes - Sleeps 8-9 hours at night with frequent awakenings; naps 2-3 times daily - No shift work - Does not drive (was afraid to get his license because of sleepiness) **Family History:** - No family history of narcolepsy or excessive sleepiness - Mother: migraine - Father: healthy - Siblings: one younger sister, healthy ### Physical Examination - **Vital Signs:** BP 118/74 mmHg, HR 72 bpm, RR 14/min, Temp 36.8°C, Weight 82 kg, Height 178 cm, BMI 25.9 kg/m² - **General:** Well-appearing young male; falls asleep during the examination on two occasions (brief, easily arousable); slightly overweight - **Epworth Sleepiness Scale (ESS):** Score 20/24 (severe excessive sleepiness) - **Stanford Sleepiness Scale:** 5/7 at time of visit ("foggy; losing interest in remaining awake") - **HEENT:** Normal oropharynx; Mallampati class II; no tonsillar hypertrophy; nasal airway patent - **Neurological:** Cranial nerves II-XII intact; motor strength 5/5 in all extremities (no weakness between cataplexy episodes); deep tendon reflexes 2+ and symmetric; coordination normal; no ataxia; gait normal - **During the examination:** One brief episode of jaw dropping and head nodding when the patient laughed at a joke — lasted approximately 10 seconds with full awareness maintained; **witnessed cataplexy** - **Mental status:** Alert (when awake); oriented x 3; affect is flat (likely related to chronic sleepiness and social withdrawal); PHQ-9 score: 12 (moderate depression) ### Workup and Results **Laboratory Studies:** | Test | Result | Reference Range | |------|--------|-----------------| | CBC | Within normal limits | -- | | CMP | Within normal limits | -- | | TSH | 2.4 mIU/L | 0.5-4.5 mIU/L | | Iron studies | Ferritin 62 ng/mL, Iron 78 μg/dL | Normal | | Urine drug screen | Negative | -- | | **CSF hypocretin-1 (orexin-A)** | **18 pg/mL** | **>200 pg/mL normal; <110 pg/mL diagnostic of NT1** | | HLA-DQB1*06:02 | **Positive** | Present in >98% of NT1 patients (but also in 25% of the general population — not diagnostic alone) | **Imaging/Additional Studies:** - **Overnight polysomnography (PSG):** - Total sleep time: 408 minutes; Sleep efficiency: 89% - Sleep latency: 3 minutes (markedly shortened) - REM latency: 8 minutes (**sleep-onset REM period — SOREMP**) - Sleep architecture: Increased N1 (22%); fragmented sleep with 38 arousals; two SOREMPs during the nocturnal recording - AHI: 2.1 events/hour (no significant sleep apnea — rules out OSA as cause of sleepiness) - PLMI: 3/hour (not significant) - No evidence of nocturnal seizures on EEG - **Multiple Sleep Latency Test (MSLT) — performed the day following PSG (sertraline held for 2 weeks prior per protocol):** - 5 nap opportunities at 2-hour intervals (09:00, 11:00, 13:00, 15:00, 17:00) - **Mean sleep latency: 2.4 minutes** (normal >8 minutes; pathological sleepiness <8 minutes; **<5 minutes consistent with severe hypersomnolence**) - **SOREMPs: 4 out of 5 naps** (REM sleep within 15 minutes of sleep onset) - MSLT diagnostic criteria for narcolepsy met: mean sleep latency <=8 minutes AND >=2 SOREMPs (including any SOREMP on the preceding PSG) - **Brain MRI:** Normal; no hypothalamic lesions, no masses, no structural abnormalities ### Clinical Image ![Diagram showing the pathophysiology of narcolepsy type 1 with hypocretin deficiency](case_02_image.jpg) *Educational diagram illustrating the pathophysiology of narcolepsy type 1, showing autoimmune destruction of hypocretin (orexin)-producing neurons in the lateral hypothalamus, and the resulting disruption of sleep-wake regulation. Source: Educational illustration.* ### Diagnosis **Narcolepsy Type 1 (Narcolepsy with Cataplexy)** **Key Diagnostic Criteria (ICSD-3):** - Excessive daytime sleepiness daily for >=3 months (present for 3 years) - Definite cataplexy: episodes of sudden, bilateral loss of muscle tone precipitated by strong emotions (laughter, surprise) with preserved consciousness — **pathognomonic for narcolepsy type 1** - MSLT: mean sleep latency 2.4 minutes (<=8 minutes) with 4 SOREMPs (>=2 required) - CSF hypocretin-1: 18 pg/mL (<110 pg/mL) — **confirmatory and considered the gold standard diagnostic test for NT1**; reflects >90% loss of hypothalamic hypocretin-producing neurons - HLA-DQB1*06:02 positive — supports autoimmune etiology (present in >98% of NT1 patients) - The classic "narcolepsy tetrad": (1) excessive daytime sleepiness (present), (2) cataplexy (present), (3) hypnagogic hallucinations (present), (4) sleep paralysis (present) — all four present in this patient (complete tetrad occurs in only ~10-15% of patients) ### Treatment Plan 1. **Pharmacotherapy for excessive daytime sleepiness:** - **First-line: Modafinil 200 mg** in the morning, may increase to 200 mg BID (morning and noon) if needed; OR - **Alternative first-line: Solriamfetol** 75 mg daily, titrate up to 150 mg (dual-action dopamine/norepinephrine reuptake inhibitor; recently approved and effective) - **If insufficient response:** Add sodium oxybate (Xyrem) 4.5 g at bedtime in two divided doses (taken at bedtime and 2.5-4 hours later); consolidates nighttime sleep, reduces cataplexy and daytime sleepiness — the only medication that addresses all narcolepsy symptoms - **Alternative:** Low-sodium oxybate (Xywav) — preferred formulation due to lower sodium content - **Second-line stimulants if needed:** Methylphenidate or dextroamphetamine (avoid if possible in a college setting due to abuse potential and scheduling concerns) 2. **Pharmacotherapy for cataplexy:** - **Continue sertraline** (or switch to venlafaxine 75-150 mg) — SSRIs/SNRIs suppress REM sleep and reduce cataplexy frequency by 50-80% - **Sodium oxybate** is the most effective anti-cataplexy agent and may replace antidepressant therapy - **Pitolisant** (histamine H3 receptor inverse agonist): 17.8-35.6 mg daily — non-scheduled, effective for both sleepiness and cataplexy 3. **Behavioral sleep management:** - **Scheduled naps:** Two 15-20 minute naps daily (between classes — e.g., 11:00 and 15:00) — brief naps are refreshing in narcolepsy and reduce sleep attack frequency - Regular sleep schedule: consistent bedtime and wake time (including weekends); avoid sleep deprivation (worsens all symptoms) - Avoid alcohol and heavy meals (worsen sleepiness and cataplexy) - Eliminate caffeine after noon; reduce energy drink consumption - Strategic timing of important activities during peak alertness 4. **Academic accommodations (coordinate with disability services):** - Document narcolepsy as a disability under ADA and Section 504 - Accommodations: extended testing time, permission to record lectures, flexible attendance policy, permission for scheduled naps, preferential seating (front row), reduced course load if needed - Academic advisor notification with student's permission 5. **Safety and driving:** - Driving evaluation after sleepiness is adequately treated and stable for >=3 months - Document treatment response and physician clearance before driving - Avoid driving during known vulnerable times (early afternoon, after meals) - Medic-Alert identification recommended 6. **Psychosocial support:** - Address secondary depression (PHQ-9: 12) — expected to improve with narcolepsy treatment and social re-engagement - Connect with narcolepsy support organizations (Narcolepsy Network, Wake Up Narcolepsy) - Educate roommate and close friends about the condition (especially cataplexy — it is not a seizure, not fainting, and not psychogenic) - Consider narcolepsy peer mentorship program 7. **Follow-up:** - Clinic visit at 2 weeks after starting medication to assess response and side effects - Monthly visits for the first 3 months, then every 3-6 months - Monitor weight (sodium oxybate can cause weight loss; stimulants can suppress appetite) - Annual evaluation: review medication efficacy, side effects, cataplexy frequency log ### Key Learning Points - Narcolepsy type 1 is caused by autoimmune destruction of hypocretin (orexin)-producing neurons in the lateral hypothalamus, resulting in near-complete loss of CSF hypocretin-1; the HLA-DQB1*06:02 allele confers susceptibility, and environmental triggers (infections, H1N1 vaccination with Pandemrix adjuvant) may initiate the autoimmune process. - The average delay from symptom onset to narcolepsy diagnosis is 8-15 years; symptoms are frequently misattributed to depression, laziness, epilepsy, or psychiatric disorders. Cataplexy, when present, is pathognomonic and should prompt immediate diagnostic workup. - The MSLT must be performed after a preceding overnight PSG (to exclude other sleep disorders and verify adequate sleep) and after discontinuation of REM-suppressing medications (antidepressants, stimulants) for at least 2 weeks (5 half-lives for fluoxetine); failure to follow this protocol invalidates results. - Sodium oxybate (gamma-hydroxybutyrate/GHB) is the only medication that addresses all four narcolepsy symptoms (sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis) and is considered the most effective single agent, though it requires careful dose titration and has abuse potential. - Abrupt withdrawal of REM-suppressing medications (SSRIs, SNRIs, TCAs) in patients with cataplexy can precipitate "status cataplecticus" — prolonged or continuous cataplexy that can be dangerous; these medications must always be tapered gradually. --- ## Case 3: Chronic Insomnia Disorder with CBT-I ### Patient Presentation **Demographics:** 42-year-old female hospital nurse (night shift), divorced mother of two **Chief Complaint:** "I haven't had a good night's sleep in over a year. I'm exhausted, but when I lie down I just can't fall asleep. I need something to help me sleep." **History of Present Illness:** The patient presents to the sleep medicine clinic reporting chronic insomnia that has progressively worsened over the past 14 months. Her insomnia began during a stressful period involving her divorce, a custody dispute, and a transition from day shifts to rotating night shifts at the hospital. Initially, she had difficulty falling asleep on nights after her ex-husband's custody weekends, but the insomnia has generalized to nearly every night regardless of the circumstances. She describes a typical pattern of going to bed at various times (ranging from 22:00 to 02:00 depending on shift schedule), lying awake for 1-3 hours with a "racing mind" reviewing the day's events, worrying about finances, and anticipating the next day's responsibilities. Once asleep, she wakes 2-3 times per night and often cannot return to sleep for 30-60 minutes. She estimates her total sleep time on most nights is 3.5-5 hours. She reports that insomnia occurs on both work nights and nights off, though it is worse after night shifts. She has developed significant anxiety about sleep itself, describing a sense of dread as bedtime approaches. She reports lying in bed watching the clock, calculating how many hours of sleep she can get "if I fall asleep right now." She has tried multiple strategies on her own, including melatonin (up to 10 mg, "doesn't work"), diphenhydramine (provides drowsiness but leaves her groggy), chamomile tea, lavender aromatherapy, and alcohol (a glass of wine before bed, which helps her feel drowsy but leads to awakenings later in the night). She spends 9-10 hours in bed most nights in an attempt to "catch up" on sleep. She uses her bed for reading, watching television, phone scrolling, eating snacks, and working on her laptop in addition to sleeping. She reports daytime fatigue, irritability, difficulty concentrating at work (she has made two minor medication errors in the past month), poor memory, and decreased motivation. She is worried about her job performance and patient safety. Her primary care physician prescribed zolpidem 10 mg three months ago, which initially helped but has become less effective. She is now requesting a higher dose or a different sleeping pill. She denies any symptoms of sleep apnea, restless legs, or parasomnia. **Past Medical History:** - Generalized anxiety disorder (chronic, worsened since divorce) - Mild depression (PHQ-9 score: 14, moderate) - Tension headaches (2-3 times per week) - Iron deficiency anemia (resolved with supplementation 2 years ago) - No surgical history - No known drug allergies **Medications:** - Zolpidem 10 mg at bedtime (started 3 months ago, diminishing effectiveness) - Escitalopram 10 mg daily (started 6 months ago for anxiety/depression) - Melatonin 10 mg at bedtime (OTC, self-prescribed, inconsistent use) - Diphenhydramine 50 mg PRN (uses 3-4 nights/week when zolpidem "doesn't work") - Acetaminophen 500-1000 mg PRN for headaches - Multivitamin daily **Social History:** - Registered nurse in a hospital ICU; works rotating shifts (mix of 12-hour day shifts and 12-hour night shifts) - Shift pattern: typically 3 night shifts in a row, then 4 days off; sometimes switches to day shifts - Divorced 14 months ago; shares custody of two children (ages 8 and 11) - Lives in a townhouse; bedroom faces a busy street with traffic noise and streetlight through the window - Drinks 4-5 cups of coffee per day, last cup typically at 16:00 (but sometimes later on night shifts) - One glass of wine most evenings - No tobacco or recreational drug use - Limited exercise; previously attended yoga classes (stopped after the divorce) - Screen time before bed: 1-2 hours (phone scrolling, social media, texting) - Has not been on vacation in over a year **Family History:** - Mother: chronic insomnia (takes benzodiazepines nightly for 20 years) - Father: no sleep issues - Sister: anxiety disorder ### Physical Examination - **Vital Signs:** BP 128/82 mmHg, HR 82 bpm, RR 16/min, Temp 36.7°C, Weight 68 kg, Height 165 cm, BMI 25.0 kg/m² - **General:** Appears fatigued with dark periorbital circles; slightly anxious; makes good eye contact; oriented and coherent - **Epworth Sleepiness Scale (ESS):** Score 10/24 (borderline — insomnia patients often report fatigue rather than sleepiness, distinguishing insomnia from hypersomnia) - **Insomnia Severity Index (ISI):** Score 22/28 (severe clinical insomnia; 0-7 none, 8-14 subthreshold, 15-21 moderate, 22-28 severe) - **Pittsburgh Sleep Quality Index (PSQI):** Global score 16 (poor sleep quality; >5 indicates poor quality) - **Fatigue Severity Scale:** 5.8/7 (significant fatigue) - **GAD-7:** 14 (moderate anxiety) - **PHQ-9:** 14 (moderate depression) - **HEENT:** Normal; Mallampati class II; no tonsillar hypertrophy - **Cardiovascular:** Regular rate and rhythm; no murmurs - **Neurological:** Intact cranial nerves; no restless legs symptoms elicited; no peripheral neuropathy; normal reflexes - **Two-week sleep diary review (completed prior to visit):** - Average time in bed: 9.5 hours - Average sleep onset latency: 75 minutes - Average number of awakenings: 2.8 per night - Average wake after sleep onset (WASO): 68 minutes - Average total sleep time: 4.6 hours - Average sleep efficiency: 48% (severely reduced; normal >85%) - No consistent circadian pattern due to rotating shifts ### Workup and Results **Laboratory Studies:** | Test | Result | Reference Range | |------|--------|-----------------| | TSH | 3.1 mIU/L | 0.5-4.5 mIU/L | | CBC | Hgb 12.8 g/dL, all within normal limits | -- | | Ferritin | 48 ng/mL | 12-150 ng/mL (adequate; rules out iron deficiency as cause of restless legs) | | CMP | Within normal limits | -- | | Cortisol (AM) | 18 μg/dL | 6-23 μg/dL (normal; rules out Cushing's or adrenal insufficiency) | **Imaging/Additional Studies:** - **Actigraphy (2-week recording):** Confirms highly irregular sleep-wake pattern; low sleep efficiency consistent with diary; rest-activity rhythms are fragmented with no consistent circadian pattern - **PSG: Not indicated** — clinical history is classic for chronic insomnia disorder without features suggestive of sleep apnea, periodic limb movements, or parasomnia; PSG is not recommended for routine insomnia evaluation per AASM guidelines - **Sleep diary analysis:** Sleep efficiency 48% (target for CBT-I: >85%); time in bed far exceeds actual sleep time (9.5 hours in bed, 4.6 hours sleeping); classic "conditioned arousal" pattern ### Clinical Image ![Diagram illustrating the cognitive-behavioral model of chronic insomnia and the 3P model](case_03_image.jpg) *Educational diagram illustrating the 3P (Predisposing, Precipitating, and Perpetuating factors) model of chronic insomnia and the components of Cognitive Behavioral Therapy for Insomnia (CBT-I). Source: Educational illustration.* ### Diagnosis **Chronic Insomnia Disorder (ICSD-3) with Comorbid Shift Work Disorder and Generalized Anxiety Disorder** **Key Diagnostic Criteria (ICSD-3):** - Difficulty initiating sleep (sleep onset latency >30 minutes) AND difficulty maintaining sleep (WASO >30 minutes) — both present - Occurs despite adequate opportunity for sleep (she spends 9.5 hours in bed) - Results in daytime impairment: fatigue, impaired concentration, mood disturbance, occupational dysfunction (medication errors) - Occurs at least 3 nights per week for at least 3 months (present for 14 months) - Not better explained by another sleep disorder (no evidence of OSA, RLS, or circadian rhythm sleep-wake disorder as primary diagnosis; shift work disorder is comorbid) **Perpetuating Factors Identified (3P Model):** - **Predisposing:** Family history of insomnia (mother), trait anxiety, hyperarousal phenotype - **Precipitating:** Divorce, custody dispute, shift work transition - **Perpetuating:** Excessive time in bed (conditioned arousal), irregular sleep schedule, bedroom used for non-sleep activities, clock-watching, caffeine use, alcohol before bed, diphenhydramine dependence, anxiety about sleep ("psychophysiological" insomnia), blue light exposure from screens, zolpidem tolerance development ### Treatment Plan 1. **Cognitive Behavioral Therapy for Insomnia (CBT-I) — first-line treatment:** CBT-I is recommended as the first-line treatment for chronic insomnia disorder by the AASM, ACP, and European Sleep Research Society, superior to pharmacotherapy for long-term outcomes. **Component 1 — Sleep Restriction Therapy (most potent behavioral component):** - Reduce time in bed to match actual total sleep time: prescribe a sleep window of 5 hours initially (e.g., 00:00 to 05:00 on nights off) - Do not go to bed until the prescribed bedtime, regardless of how tired she feels - Set a fixed wake time (05:00) every day — including days off and weekends — to anchor the circadian rhythm - When sleep efficiency reaches >85% for 5 consecutive days, increase time in bed by 15-minute increments - Minimum prescribed time in bed: never below 5 hours (safety threshold) - **Warning:** Sleepiness will initially worsen — critical to ensure patient safety, especially given her nursing duties; may need temporary shift modification **Component 2 — Stimulus Control Therapy:** - Bed is for sleep and sex only — remove the TV, laptop, phone, and reading materials from the bedroom - Go to bed only when sleepy (not just tired) - If unable to fall asleep within approximately 20 minutes (do not clock-watch — estimate by feeling), get out of bed, go to another room, engage in a quiet, non-stimulating activity (reading a physical book under dim light), and return to bed only when sleepy - Repeat the above rule for middle-of-the-night awakenings - No napping (with exception for shift work safety — see below) **Component 3 — Cognitive Therapy:** - Identify and challenge dysfunctional beliefs about sleep: "I need 8 hours or I can't function," "If I don't fall asleep soon, tomorrow will be ruined," "My insomnia is destroying my health" - Cognitive restructuring: replace catastrophic thoughts with realistic appraisals - Address the paradox of effort: trying harder to sleep increases arousal and worsens insomnia - Reduce clock-watching behavior: turn clocks away from the bed, remove the phone from the bedroom **Component 4 — Sleep Hygiene Education:** - Stop caffeine after 12:00 noon (caffeine half-life 5-7 hours) - Eliminate alcohol as a sleep aid (alcohol fragments sleep architecture, suppresses REM, and causes rebound awakenings) - Blackout curtains for the bedroom (critical for daytime sleep after night shifts and to block streetlight) - White noise machine or earplugs for traffic noise - Cool bedroom temperature (18-19°C / 65-67°F) - Avoid screens for 60 minutes before bed (blue light suppresses melatonin); use blue-light-blocking glasses if screen use is unavoidable - Regular exercise (resume yoga or walking) — but not within 3 hours of bedtime **Component 5 — Relaxation Training:** - Progressive muscle relaxation (PMR) — 20 minutes before bed - Diaphragmatic breathing exercises - Option: mindfulness-based stress reduction (MBSR) — particularly helpful given comorbid anxiety 2. **Shift Work Disorder Management:** - Advocate for a fixed shift schedule (preferably permanent night shift or permanent day shift) rather than rotating shifts — rotating shifts make circadian entrainment impossible - Strategic light exposure: bright light (10,000 lux light box) during the first half of the night shift to promote alertness; dark sunglasses on the commute home to avoid morning light-induced circadian reset - Melatonin 0.5-1 mg (not 10 mg — physiological dose) taken 30 minutes before desired daytime sleep after night shifts - Strategic napping: 20-minute nap before night shifts (prophylactic napping) is evidence-based for shift worker safety 3. **Medication management:** - **Taper zolpidem gradually** (reduce by 5 mg every 1-2 weeks) — prolonged use leads to tolerance, dependence, and worsens insomnia long-term (rebound insomnia); zolpidem also impairs next-day psychomotor performance (FDA black box warning at 10 mg in women) - **Discontinue diphenhydramine** — anticholinergic effects, cognitive impairment, tolerance development, and associated with increased dementia risk with chronic use - **Continue escitalopram** 10 mg — may consider dose optimization to 20 mg if anxiety and depression do not improve with CBT-I and improved sleep - **Melatonin:** Reduce dose to 0.5-1 mg (physiological dose; 10 mg is supratherapeutic and may cause morning grogginess); use specifically for shift work circadian realignment, not as a hypnotic 4. **Occupational safety:** - Discuss medication errors with occupational health in a supportive framework - Request temporary schedule accommodation during initial sleep restriction therapy (most sleep-deprived period) - Document sleep disorder diagnosis for workplace protections 5. **CBT-I delivery:** - Structured 6-8 session program (weekly sessions, 50 minutes each) with a trained CBT-I therapist - Option: digital CBT-I (e.g., Somryst/Pear Therapeutics FDA-cleared platform, or Sleepio) if in-person sessions are inaccessible due to work schedule - Ongoing sleep diary completion throughout treatment (essential for monitoring progress and titrating the sleep window) 6. **Follow-up schedule:** - Weekly during active CBT-I (6-8 weeks) - Biweekly during zolpidem taper - Monthly for 3 months after completing CBT-I - Sleep diary and ISI score at each visit - Reassess at 3 months: if ISI <8 (remission), transition to maintenance; if ISI remains >14, consider adjunctive pharmacotherapy (low-dose doxepin 3-6 mg — FDA-approved for sleep maintenance insomnia, or suvorexant 10-20 mg — dual orexin receptor antagonist) ### Key Learning Points - CBT-I is the recommended first-line treatment for chronic insomnia disorder in all major guidelines (AASM, ACP, ESRS), with response rates of 70-80% and sustained benefit at 1-year follow-up, unlike hypnotic medications which lose efficacy and carry risks of dependence and cognitive impairment. - Sleep restriction therapy — the most potent component of CBT-I — works by building homeostatic sleep pressure through mild sleep deprivation, consolidating sleep into a shorter, more efficient window, and breaking the conditioned association between the bed and wakefulness. Initial worsening of sleepiness is expected and must be managed with safety precautions. - Chronic use of sedative-hypnotics (zolpidem, benzodiazepines, diphenhydramine) for insomnia is associated with tolerance, dependence, rebound insomnia on discontinuation, cognitive impairment, falls (especially in elderly), complex sleep behaviors (sleep-driving, sleep-eating), and potential association with dementia; guidelines recommend limiting use to 2-4 weeks. - The physiological dose of melatonin for circadian entrainment is 0.5-1 mg, not the 5-10 mg doses commonly available OTC; higher doses may paradoxically worsen sleep through morning grogginess, desensitization of melatonin receptors, and disruption of endogenous melatonin rhythm. - Rotating shift work is a significant independent risk factor for chronic insomnia, and circadian misalignment cannot be adequately treated with CBT-I alone; workplace schedule modification, strategic light/dark exposure, and properly timed low-dose melatonin are essential adjuncts for shift workers with insomnia.