Insomnia

Sleep disorders are sorted by which of three complaints a patient presents with: difficulty initiating or maintaining sleep, excessive daytime sleepiness, or abnormal behavior during sleep. Diagnosis proceeds from history, sleep diary, and bed-partner account through actigraphy to polysomnography and, when hypersomnolence is unexplained, a multiple sleep latency test. Management is complaint-specific: cognitive behavioral therapy for insomnia, airway pressure for sleep apnea, stimulants for narcolepsy, iron and a dopamine agonist for restless legs syndrome, and safety measures with melatonin or clonazepam for parasomnias.

Obstructive sleep apnea is repetitive upper airway collapse during sleep, diagnosed by an apnea-hypopnea index of 5 or more per hour with symptoms, or 15 or more per hour regardless of symptoms, and treated first with weight loss plus positive airway pressure.

Narcolepsy is a chronic central disorder of hypersomnolence marked by irresistible, recurrent daytime sleep attacks, most often from loss of orexin (hypocretin) producing neurons in the lateral hypothalamus; cataplexy, when present, is considered pathognomonic. Diagnosis follows a normal overnight polysomnogram and a multiple sleep latency test showing shortened sleep latency and rapid sleep-onset REM. Manage first with scheduled naps and sleep hygiene, then a wakefulness-promoting agent such as modafinil, adding pitolisant or sodium oxybate specifically for cataplexy.

Major depressive disorder is a mood disorder defined by 5 or more of 9 major depressive episode symptoms, including depressed mood or anhedonia, present nearly every day for at least 2 weeks and causing significant functional impairment. Diagnosis is clinical, screened with the Patient Health Questionnaire. First-line treatment is cognitive behavioral therapy, a selective serotonin reuptake inhibitor (SSRI) such as sertraline, or both, escalating to augmentation, esketamine, or electroconvulsive therapy for refractory or acutely suicidal presentations.

Generalized anxiety disorder is excessive, hard-to-control worry about multiple life domains occurring more days than not for at least 6 months, with at least 3 of 6 associated physical symptoms and functional impairment. Screen with the GAD-7 after excluding hyperthyroidism and substance use, then treat first-line with cognitive behavioral therapy and/or an SSRI or SNRI such as escitalopram or venlafaxine extended-release, reserving benzodiazepines for short-term severe symptom control only.

Posttraumatic stress disorder follows exposure to actual or threatened death, serious injury, or sexual violence, producing intrusive re-experiencing, avoidance, negative alterations in cognition and mood, and hyperarousal that persist beyond 1 month with significant distress or impairment. First-line treatment is trauma-focused cognitive behavioral therapy combined with an SSRI or SNRI, with prazosin added for persistent nightmares.

Alcohol withdrawal syndrome is a staged, timeline-bound hyperexcitability state that follows abrupt cessation or reduction of heavy alcohol use, progressing from minor symptoms through alcoholic hallucinosis and withdrawal seizures to delirium tremens, a medical emergency with mortality as high as 5%. Diagnosis is clinical and severity is graded with the CIWA-Ar; first-line treatment is symptom-triggered benzodiazepine dosing plus thiamine given before glucose.

Hyperthyroidism is the clinical syndrome of thyroid hormone excess, produced by a range of causes from Graves disease and autonomously functioning nodules to destructive thyroiditis and exogenous hormone ingestion. Diagnosis begins with a suppressed thyroid-stimulating hormone and elevated free thyroxine, followed by radioactive iodine uptake testing or antibody measurement to identify the cause, and first-line treatment is a beta blocker for symptom control while the underlying cause directs thionamide, radioactive iodine ablation, or thyroidectomy therapy.