Obstructive sleep apnea is a major medical disorder that happens during sleep — repeated upper airway collapse producing fragmented NREM sleep, intermittent hypoxia, and sympathetic surges. The cardiovascular and cognitive consequences are substantial. Estimated prevalence: 10-30% of adults; far more common than diagnosed because many cases remain unrecognized.
The mechanism: during sleep, pharyngeal muscle tone decreases. In OSA patients, the airway is anatomically narrow (often related to obesity, but also craniofacial structure, tonsil/adenoid size, soft palate position) and collapses repeatedly. Each collapse: oxygen saturation drops, CO2 rises, sympathetic nervous system surges, brief arousal restores muscle tone and reopens airway. The patient returns to sleep, the cycle repeats. May happen 30-100+ times per hour in severe disease.
Clinical presentation: bed partner often the historian — loud snoring, witnessed apneas, gasping or choking arousals. Patient symptoms: daytime sleepiness (often dismissed as "I just need more sleep"), morning headaches, dry mouth on awakening, nocturia, mood symptoms, cognitive difficulties. Many patients don't recognize their symptoms.
Cardiovascular consequences: the diagnosis is consequential because of what untreated OSA does to the body:
Hypertension — particularly resistant hypertension (3+ medications still uncontrolled). OSA evaluation is appropriate in resistant HTN.
Atrial fibrillation — OSA substantially increases AFib risk; treatment improves AFib outcomes.
Stroke — independent risk factor.
Heart failure — both new development and worsening of existing HF.
Coronary artery disease, cardiac arrhythmias, pulmonary hypertension.
Other consequences: accelerated cognitive aging, increased dementia risk, depression and anxiety, accidents (particularly motor vehicle crashes), reduced quality of life.
Diagnosis: home sleep apnea testing (HSAT) is increasingly used for uncomplicated suspected OSA in adults. Polysomnography (PSG) in sleep lab for complex cases, suspected other sleep disorders, or after failed HSAT. AHI (Apnea-Hypopnea Index) defines severity: 5-15 mild, 15-30 moderate, >30 severe.
Treatment:
CPAP (continuous positive airway pressure) remains the most effective treatment for moderate-to-severe OSA. Adherence is the challenge — modern devices with heated humidification, auto-titration, BiPAP for high-pressure needs, better mask fitting substantially improve tolerance. Goal: >4 hours/night usage on >70% of nights.
Mandibular advancement devices for mild-moderate OSA or CPAP intolerant — custom oral appliances that hold the lower jaw forward.
Weight loss substantially improves OSA. Bariatric surgery often produces dramatic improvement.
Positional therapy for positional-dependent OSA.
Surgical options for selected patients — uvulopalatopharyngoplasty (UPPP), hypoglossal nerve stimulation (Inspire), bariatric surgery.
Avoid medications that worsen OSA: benzodiazepines, opioids, alcohol — all relax pharyngeal muscles.
Implications for psychiatric practice: screen for OSA in patients with treatment-resistant depression, hypertension on multiple medications, atrial fibrillation, ADHD-like symptoms in adults. Many "treatment-resistant" psychiatric presentations have untreated OSA contributing.
When you encounter a patient with possible OSA, evaluation is appropriate — treatment changes cardiovascular trajectory and improves multiple other outcomes. OSA is cardiovascular disease that happens during sleep.