Obstructive sleep apnea is among the most prevalent and most undertreated conditions in adult medicine. Population-level prevalence in adults is approximately 10–30% in middle age and rises to 30–50% in adults over 60, depending on how the diagnostic criteria are defined and the population studied. Among adults with diagnosable sleep apnea, approximately 80% are undiagnosed at any given time. Among psychiatric populations specifically, prevalence is higher — the overlap with depression, anxiety, refractory illness, and obesity is substantial — and the diagnosis is even more often missed because psychiatric symptoms divert clinical attention from the underlying sleep disorder.
The biology of intermittent hypoxia is the mechanism that matters. During apneic events, blood oxygen saturation drops repeatedly through the night, often dozens or hundreds of times. The brain experiences a chronic intermittent hypoxic stress that, over years, produces measurable consequences: cerebrovascular damage from oxidative stress, neuroinflammation, hippocampal volume loss, increased amyloid burden, and accelerated cognitive aging. Apnea is also associated with cardiovascular consequences — hypertension, atrial fibrillation, cardiovascular mortality — that themselves drive cognitive risk. The cognitive cost of untreated apnea, accumulated across a decade, is among the larger single contributors to dementia risk in the population.
Psychiatric presentation often masks the diagnosis. The patient with apnea presents with daytime fatigue, mood symptoms, attention problems, cognitive complaints — symptoms that map cleanly onto depression, anxiety, ADHD, and early MCI. The clinical encounter focuses on the psychiatric symptoms; the sleep apnea is missed. The patient receives an antidepressant or stimulant or sleep aid that addresses the surface symptoms partially while the underlying apnea continues unchecked. The clinical discipline of longevity psychiatry is to screen for apnea in every patient with refractory mood, cognitive, or fatigue symptoms — and not only in patients who fit the classic profile of male, obese, snoring, witnessed apneas. Women, non-obese patients, and atypical presentations are precisely the ones most often missed.
The diagnostic pathway is more accessible than it used to be. Home sleep apnea testing (HSAT) has emerged as a low-cost, high-availability first-line option for patients with high pre-test probability of moderate-to-severe OSA. HSAT is appropriate for screening in many patients; it is less accurate in mild cases, in patients with significant comorbidity, and in patients with central sleep apnea. Formal in-laboratory polysomnography remains the gold standard for ambiguous cases, central apnea, complex sleep disorders, and pediatric cases. The clinical move is to lower the threshold for testing dramatically — particularly in patients in the acceleration window with any psychiatric, cognitive, or cardiovascular symptoms.
CPAP is the dominant treatment but adherence is the central practical problem. Approximately 50% of patients prescribed CPAP discontinue use within the first year, and many of the remainder use it for fewer than the four hours per night threshold associated with cognitive benefit. The clinical work is not just prescribing CPAP — it is following up at two weeks, six weeks, three months, and beyond, troubleshooting mask fit, pressure tolerance, claustrophobia, and the partner-relationship dynamics that often surface. CPAP that the patient does not wear is no treatment at all. The longevity-psychiatry conversation includes adherence support as actively as it includes the prescription.
Alternatives to CPAP have expanded. Auto-titrating positive airway pressure (APAP) is now the default for many patients — it self-adjusts and is often better tolerated. Bilevel PAP (BiPAP) is appropriate for patients who cannot tolerate single-pressure CPAP or who have specific patterns of central apnea. Oral mandibular advancement devices, fitted by sleep dentists, are appropriate for mild-to-moderate OSA in patients who decline or cannot tolerate PAP therapy. Hypoglossal nerve stimulation (Inspire device) is FDA-approved for moderate-to-severe OSA in selected patients who fail CPAP. Maxillomandibular advancement surgery and other surgical options exist for specific anatomic situations. The clinical implication: there is almost always an option for the patient who cannot or will not tolerate CPAP.
The longevity-psychiatry implication is that every patient in the acceleration window deserves an explicit apnea evaluation. Not a check-box question. An actual assessment — STOP-BANG or similar validated screener at minimum, with low threshold for HSAT or polysomnography, and aggressive follow-through on adherence when treatment begins. The single greatest unrealized cognitive intervention in most populations is the apnea evaluation that has not been done.