“…Although "sleep disturbance" is reported by two-thirds of RA patients (7), their sleep physiology and objective evidence of daytime sleepiness have not been fully characterized. Sleep abnormalities in RA patients might include I ) interference of sleep by joint pain, resulting in sleep deprivation (&lo), 2) disordered breathing during sleep, related to anatomic lesions including craniovertebral junction abnormalities, such as atlantoaxial dislocation (1 1,12), acquired micrognathia ( 13), or cricoarytenoid joint involvement (14), or 3) periodic leg movements of sleep (nocturnal myoclonus) (15). Other causes of daytime fatigue in RA patients, however, might include 1) depression (16), 2) chronic insomnia, 3) "nonrestorative sleep," as described in patients with fibrositis (17,18), or 4) some as-yet-unidentified factor.…”