Parkinson Disease and Sleep Disorders: What’s the Connection?

Sleep disturbances such as insomnia, REM sleep behavior disorder (RBD), and excessive daytime sleepiness (EDS) not only are common among persons with advanced Parkinson disease (PD), but also often present early in the course of PD. And while sleep disorders are increasingly being recognized as a prodromal symptom of PD, a complete understanding is lacking about their prevalence, the connection between different types of sleep disorders, and how they progress over time in the prodromal and early stages of PD.

Thus, a group of researchers set out to explore the longitudinal changes in the prevalence of different sleep disorders among persons with PD. They presented their findings at the 2018 International Congress of Parkinson's Disease and Movement Disorders in Hong Kong on October 8, 2018.

Using data from the Parkinson Progression Markers Initiative—a landmark observational clinical study to comprehensively evaluate PD cohorts in order to identify biomarkers of PD progression—the authors identified participants with insomnia, RBD, and/or EDS. In all, 218 participants with a completed 5-year clinical follow-up were included.

At the outset of the study, 55.5% of participants had no reported sleep disorder, while 31.7% reported having 1 sleep disorder (insomnia, 12.8%; RBD, 10.6%, EDS, 8.3%) and 11.5% reported having 2 sleep disorders (EDS and RBD, 5.0%; insomnia and RBD, 4.1%; insomnia and EDS, 2.3%). Only 1.4% of participants reported having all 3 sleep disorders concomitantly.

At 5-year follow-up, the number of participants reporting no sleep disorder dropped to 30.3%. The number reporting 1 sleep disorder increased to 39.0% (insomnia, 19.3%; RBD, 11.0%, EDS, 8.7%), and the number reporting 2 sleep disorders rose to 23.4% (EDS and RBD, 5.5%; insomnia and RBD, 7.3%; insomnia and EDS, 10.6%). The number reporting all 3 sleep disorders rose to 7.3%.

The largest increase in reported prevalence was seen for insomnia, followed by EDS and then RBD. “At baseline, 20.6% of PD subjects reported insomnia which increased to 55.5% at 5 years (p<0.001); 17.0% of PD subjects reported EDS which increased to 32.1% at 5 years (p<0.001); 21.1% of PD subjects reported RBD, which increased to 31.2% at 5 years (p=0.005),” the authors wrote.

Roughly a third of the patients with PD in the study remained free of sleep disturbances 5 years into the course of the disease. “The greatest reported increase in prevalence over the 5-year period was observed for insomnia, followed by EDS and RBD. The number of patients with multiple sleep disorders was relatively low suggesting that they can have different pathogenesis,” they concluded.

—Michael Gerchufsky

Reference:
Xu Z, Anderson K, Lawson R, Brooks DJ, Pavese N. Progression of sleep disorders spectrum in Parkinson’s disease: a 5 year clinical longitudinal study. In: Abstracts of the 2018 International Congress of Parkinson's Disease and Movement Disorders. Mov Disord. 2018;33(suppl 2):S1-S929. doi:10.1002/mds.116. Abstract 1641. http://www.mdsabstracts.org/abstract/progression-of-sleep-disorders-spectrum-in-parkinsons-disease-a-5-year-clinical-longitudinal-study/. Accessed October 12, 2018.