Restlessness is related to Parkinson disease and not necessarily dopaminergic treatment, according to a study published in the Journal of Neurological Sciences.
This cross-sectional study investigated restless leg syndrome (RLS), leg motor restlessness (LMR), and their variants in Parkinson disease and associated disorders. Researchers reviewed participants diagnosed with Parkinson disease (n=63), multiple system atrophy (MSA) (n=17), or progressive supranuclear palsy (PSP) (n=11) on a variety of assessments for sleep status, mental state, autonomic symptoms, nonmotor symptoms, and levodopa treatment. Participants with PSP had higher Hoehn and Yahr (H-Y) stages compared with participants with PD. The untreated population comprised patients with PD (41.3%), MSA (82.4%), and PSP (36.4%).
In comparison to participants with PD, “participants [with MSA] exhibited lower levodopa equivalent dose, lower scores on PD sleep scale-2 (PDSS-2), and higher scores of Scales for Outcomes in PD-Autonomic (SCOPA-AUT).” Participants with PD had higher scores on Non-Motor Symptom Scale (NMSS) in comparison with participants with MSA and PSP. There were variations in the frequency of RLS, LMR, and LMR variants amongst the groups evidenced by PD group (12.7%, 11.1% and 1.6%, respectively), MSA (5.9%, 11.8% and 0%, respectively), and PSP (0%, 9.1% and 0%, respectively).
Restlessness without the urge to move was not observed in participants with PSP but was seen in participants with PD (25.4%) and MSA (11.8%). Differences such as higher H-Y stage; higher scores on SCOPA-AUT, PDSS-2, and Beck Depression Inventory – II; higher rate of dopamine agonist; and a trend toward a higher levodopa equivalent doses were observed in participants with PD with restlessness in comparison with participants without. There was a positive correlation between International Restless Legs Syndrome Study Group rating scale and SCOPA-AUT (R=.48, P<.05).
Study limitations included a lack of statistical power resulting from a small number of participants with MSA and PSP. The age of onset for RLS and LMR were not evaluated. Additional cognitive assessments to evaluate other cognitive impairment profiles associated with PD, other than dementia, were also lacking.
Taken together, the investigators posit that there are associations between restlessness in patients with PD and disease severity, autonomic symptoms, sleep disturbances, and depressive symptoms.
This work was supported by JSPS KAKENHI Grant Number JP16K21319.
Matsubara T, Suzuki K, Fujita H, et al. Restless legs syndrome, leg motor restlessness and their variants in patients with Parkinson’s disease and related disorders. J Neur Sci. 2018; 393:51-57.