Activity-rest rhythm abnormalities in parkinson's disease patients are related to dopaminergic therapy

Abstract

Objectives: To compare going to bed, waking-up, and immobility onset and offset times in Parkinson's disease (PD) patients receiving levodopa and/or dopamine agonists (i.e., dopaminergic therapy or DT) with "de novo" patients and healthy controls and to correlate these parameters with self-reported sleep disturbances. Methods: Fifteen "de novo" and 60 PD patients on DT were included in the study. Twenty-three subjects without history of sleep complaints and similar age and sex distributions as the PD patients served as controls. Going to bed and waking-up times were registered in 7-day sleep logs. Nocturnal immobility onset and offset times were measured using actigraphy. Sleep disorders were assessed applying the PD sleep scale (PDSS). Results: Patients on DT showed earlier waking-up and immobility offset times (40 min) compared with controls and "de novo" patients. Multivariable regression analysis showed that DT but not Hoehn & Yahr score was a significant and independent predictor of early awakening time (OR 4.0, 95 CI 1.1514.13). Patients manifesting more frequent nighttime psychotic symptoms and more frequent daytime somnolence showed earlier going to bed and waking-up times. Conclusions: Results suggest that activityrest rhythm alteration in PD may be a consequence of DT but not of disease stage. Altered sleep cycles correlated with diurnal somnolence and nocturnal psychosis.