Syndrome of Acute Anxiety Among Marines After Recent Arrival at High Altitude

Abstract

Management of mental health is critical for maintenance of readiness in austere military environments, Emerging evidence implicates hypoxia as an environmental trigger of anxiety spectrum, symptomatology. One thousand thirty-six, unacclimatized infantry Marines ascended from sea level to the Marine Corps Mountain Warfare Training Center (2,061-3,383 in) for a 30-day exercise. Within the first 6 days of training, 7 servicemen presented with severe, acme anxiety/panic with typical accompanying signs of sympathetic activation and no classic symptoms of acute mountain sickness (including headache). Four had a history of well-controlled psychiatric diagnoses. Invariably, cardiopulmonary and neurological evaluations were mi revealing, and acute cardiopulmonary events were excluded Within limits of expeditionary diagnostic capabilities All patients responded clinically to oxygen, rest, and benzodiazepines returning to baseline function the same day. The unexpected onset of 7 cases of acute anxiety, symptomatology coincident with recent arrival al moderate-to-high altitudes represents a highly unusual incidence and temporal distribution, suggestive of hypobaric hypoxemia as the proximal cause. We propose acute hypoxic physiological, anxiety (AHPA) as a unique member of the spectrum of altitude-associated neurological disorders. Recognition of AHPA is particularly relevant in a military population: warfighters with anxiety spectrum diagnoses may have a recognizable and possibly preventable vulnerability.