To evaluate the impact of sleep disorders on non-motor symptoms in patients with Parkinson disease (PD).
This was a cross-sectional study. Patients with PD were evaluated for obstructive sleep apnea (OSA), restless legs syndrome (RLS), periodic limb movement syndrome (PLMS), and REM sleep behavior disorder (RBD). Cognition was assessed with the Montreal Cognitive Assessment and patients completed self-reported questionnaires assessing non-motor symptoms including depressive symptoms, fatigue, sleep complaints, daytime sleepiness, and quality of life.
86 patients with PD (mean age = 67.4 ± 8.8 years; range: 47-89; 29 women).
Measurements and Results:
Having sleep disorders was a predictor of overall non-motor symptoms in PD (R2 = 0.33, p < 0.001) while controlling for age, PD severity, and dopaminergic therapy. These analyses revealed that RBD (p = 0.006) and RLS (p = 0.014) were significant predictors of increased non-motor symptoms, but OSA was not. More specifically, having a sleep disorder significantly predicted sleep complaints (ΔR2 = 0.13, p = 0.006), depressive symptoms (ΔR2 = 0.01, p = 0.03), fatigue (ΔR2 = 0.12, p = 0.007), poor quality of life (ΔR2 = 0.13, p = 0.002), and cognitive decline (ΔR2 = 0.09, p = 0.036). Additionally, increasing number of sleep disorders (0, 1, or ≥ 2 sleep disorders) was a significant contributor to non-motor symptom impairment (R2 = 0.28, p < 0.001).
In this study of PD patients, presence of comorbid sleep disorders predicted more non-motor symptoms including increased sleep complaints, more depressive symptoms, lower quality of life, poorer cognition, and more fatigue. RBD and RLS were factors of overall increased non-motor symptoms, but OSA was not.
Neikrug AB; Maglione JE; Liu L; Natarajan L; Avanzino JA; Corey-Bloom J; Palmer BW; Loredo JS; Ancoli-Israel S. Effects of sleep disorders on the non-motor symptoms of Parkinson disease. J Clin Sleep Med 2013;9(11):1119-1129.