Sleep apnea is a common disorder characterized by repeated interruptions in breathing during sleep, which prevents the body from achieving restorative rest. This condition generally manifests in two primary forms: Obstructive Sleep Apnea (OSA), where the airway physically collapses, and Central Sleep Apnea (CSA), where the brain temporarily fails to send the correct signals to the muscles controlling breathing. Military service history, encompassing both active duty and veteran status, is significantly associated with higher rates of sleep apnea diagnoses compared to the general civilian population. This link suggests unique experiences and exposures during service contribute to the development of this chronic sleep disorder.
Defining the Increased Prevalence
Diagnosis rates of sleep apnea are substantially higher in the military population than in the civilian population. Studies show the prevalence of Obstructive Sleep Apnea (OSA) in veterans is more than double that of non-veterans, with rates documented around 21% for veterans compared to approximately 9% in the comparable non-veteran population. This elevated risk is particularly pronounced in those who have deployed.
Furthermore, veterans are often diagnosed with OSA at a younger age, sometimes an average of five years earlier than their civilian counterparts. While OSA accounts for the majority of cases, Central Sleep Apnea (CSA) is an important consideration due to its potential link with neurological injuries. In specific cohorts of veterans, particularly those seeking mental health treatment, the risk of screening high for OSA can reach 69%.
Unique Military Service Risk Factors
The increased prevalence of sleep apnea is attributed to several unique stressors and traumatic exposures inherent to military service.
Traumatic Brain Injury (TBI)
Traumatic Brain Injury (TBI) is a recognized contributor, often resulting from exposure to blast waves in combat zones. Even mild TBI can disrupt the central nervous system’s control over respiratory function, increasing the risk for Central Sleep Apnea (CSA) by altering the brain’s signals to the breathing muscles. TBI can also contribute to Obstructive Sleep Apnea (OSA) by causing incoordination or weakening of the throat muscles, which normally keep the upper airway open during sleep. The primary blast wave itself can induce subtle, long-lasting damage to neural networks that regulate sleep-wake cycles and breathing patterns.
Environmental Exposures
This neurological disruption is compounded by environmental factors encountered during deployment, such as exposure to burn pits. The combustion of waste materials in open-air burn pits releases fine particulate matter (PM) and volatile organic compounds (VOCs) that are inhaled. This inhalation triggers a persistent inflammatory response in the upper respiratory tract. Chronic inflammation and tissue damage cause the tissues lining the pharynx and nasal passages to swell (edema), leading to a physical narrowing and obstruction of the airway during sleep.
Operational Stress and Sleep Disruption
Beyond trauma and toxic exposure, the high operational tempo of military life introduces chronic sleep disruption as a significant risk factor. Operational demands often necessitate irregular shift work, sustained periods of wakefulness, and rapid changes in sleep-wake schedules, leading to circadian misalignment. This chronic insufficient sleep impacts metabolic and cardiovascular health, which can predispose individuals to sleep apnea. Furthermore, the cultural pressure to operate under constant stress can mask or worsen initial symptoms, delaying diagnosis and treatment.
The Interplay with Comorbid Conditions
Sleep apnea rarely occurs in isolation within the military population and often exists in a complex, reciprocal relationship with other highly prevalent conditions.
Post-Traumatic Stress Disorder (PTSD)
One of the strongest connections is the bidirectional link with Post-Traumatic Stress Disorder (PTSD). The chronic hyperarousal state characteristic of PTSD interferes with deep sleep, increasing muscle tension and making the upper airway more susceptible to collapse, thus worsening Obstructive Sleep Apnea (OSA). Conversely, the repeated drops in blood oxygen and fragmented sleep caused by untreated sleep apnea exacerbate PTSD symptoms, leading to increased anxiety, irritability, and cognitive difficulties during the day. This compounding effect creates a vicious cycle where each condition fuels the severity of the other. The overlap is so significant that many studies recommend mandatory OSA screening for all veterans presenting with PTSD.
Chronic Pain
Sleep apnea is also closely linked to chronic pain, a common result of training and combat injuries. Chronic pain often causes sleep fragmentation. However, the poor sleep quality and daytime fatigue resulting from OSA can also lower an individual’s pain threshold, increasing sensitivity to existing pain. Chronic pain can also restrict mobility, potentially leading to weight gain, which is a known physiological risk factor for developing OSA.
Depression
This relationship extends to mental health conditions like depression, which is highly associated with service. The chronic oxygen deprivation and persistent, non-restorative sleep caused by sleep apnea can directly contribute to the development of depressive symptoms. In veterans, the co-occurrence of sleep apnea with conditions like major depressive disorder or chronic pain often results in greater overall morbidity and more difficulty in managing symptoms.