Sleep disturbances in probable multiple system atrophy

Multiple system atrophy (MSA) is a fatal alpha-synucleinopathy characterized by variable combinations of parkinsonism, autonomic and cerebellar dysfunction. Sleep in MSA is highly compromised due to various sleep disturbances. Disrupted sleep-wake cycles in MSA contribute to poor health-related quality of life and are negative prognostic factors.

We aimed to study the various sleep disturbances; the effect of parkinsonian and cerebellar phenotypes on sleep; and the correlation of sleep parameters with disease severity in an Asian-Indian cohort of probable MSA patients.

We recruited 60 probable MSA patients (MSA-P = 19; MSA-C = 41). Disease severity was assessed using UPDRS-III, UMSARS-I and UMSARS-II. Detailed history and relevant sleep questionnaires were applied to evaluate the sleep disturbances.

Sleep disturbances were universally observed in probable MSA patients in this cohort. These include REM behavior disorder (RBD)-95 %; poor sleep quality-80 %; secondary insomnia and intermittent awakenings-100 %; excessive daytime sleepiness-26 %; risk for obstructive sleep apnea-51.7 % and snoring-85 %. MSA patients reported 38.2 ± 22.9 percentage improvement in sleep with the medications. There was no significant difference between probable MSA-P and MSA-C patients in any of the sleep parameters. Sleep quality was poor in patients with pre-motor RBD than post-motor RBD (p < 0.01). Poor sleep quality had a moderate positive correlation with RBD duration. Disease severity positively correlated with RBD duration and poor sleep quality.

Sleep disturbances, the negative prognostic factors, were universally observed in this Asian Indian MSA cohort. This study provides supporting evidence that RBD might play a possible role in MSA disease severity, progression, and sleep quality.