Sleep in ALS: more than discomfort or respiratory breathing disorder

Amyotrophic lateral sclerosis (ALS) may directly affect sleep through immobilisation, fasciculations, muscle cramps, pain (musculoskeletal but also neuropathic) impaired swallowing function (with consequent sialorrhea, choking and saliva aspiration), or through specific sleep disorders, worsening physical and mental health and increasing the burden of the disease. The more prominent sleep disorders in patients with ALS are represented by sleep-related breathing disorders (SRBD) (45%–60%), sleep motor disorders (restless legs syndrome (RLS) and periodic limb movement disorder (PLMD), respectively, about 15% and 50%), rapid eye movement (REM) parasomnias (5%–20%), insomnia (65%, probably overestimated given that sleep could be fragmented or reduced secondary to other sleep disorders) and circadian rhythm …