Autonomic Regulation and Sweating During REM Sleep

Physiological Mechanisms

• In patients with congenital central hypoventilation syndrome (CCHS), hypoventilation occurs during all sleep stages but is typically less severe during REM sleep compared to non-REM sleep 1
• Thoracoabdominal asynchrony, a well-known phenomenon during REM sleep in infants, occurs due to loss of rib cage stabilization from inspiratory intercostal muscle inhibition 2, 3
• During REM sleep, the typical pattern of thoracoabdominal asynchrony includes paradoxical rib cage movement during inspiration in children with chronic lung disease 4

Clinical Implications

• In REM sleep behavior disorder (RBD), autonomic dysregulation may occur alongside the loss of normal muscle atonia, though sweating is not a primary feature 5, 6
• Medications, particularly serotonergic antidepressants, can induce or exacerbate REM sleep abnormalities and potentially affect autonomic functions including sweating 6

Diagnostic Approach

• The American Academy of Sleep Medicine recommends polysomnography to confirm the diagnosis when abnormal sweating during sleep is reported, allowing differentiation between various sleep disorders 7

Causes of Sweating During REM Sleep

Physiological Mechanisms in REM Sleep

• During REM sleep, muscle tone reaches its nadir and upper airway muscles (except nasal and laryngeal dilators) become atonic, which can contribute to autonomic instability 8, 9

Pathological Causes of REM Sleep Sweating

Circadian and Inflammatory Factors

• Cortisol nadir, increased skin temperature, and poor barrier function during nighttime hours can promote sweating, particularly in inflammatory conditions 8, 9
• Circadian dysregulation with shifted cortisol rhythms and increased melatonin levels may result in increased systemic inflammation that triggers sweating 8, 9