Letter to the editor

Musculoskeletal problems are common in the general population and also in Parkinson’s disease (PD) patients. We aimed to assess whether socioeconomic status (SES) is associated with the prevalence of musculoskeletal problems in PD patients.

This cross-sectional study used data a total of 309 patients with PD who were interviewed, and their medical records were reviewed from the Movement Disorder Clinic of Seoul National University Hospital from March to December 2016. The PD patients were divided into four age groups. Education level was divided into three groups: primary school, middle and high school, and college or higher. Monthly household income was divided into four groups. Occupation was divided into three groups: manual workers, non-manual workers, and others (unemployed and housewives).

Patients with musculoskeletal problems were more likely to be women and older, had a more impaired Activities of Daily Living and depressive symptoms and less education, and were less likely to be engaged in non-manual work. For both genders, SES had no association with musculoskeletal problems. For men, similar to the patients overall, age had a positive association with musculoskeletal problems. The Unified Parkinson’s Disease Rating Scale I & II scores also had positive associations with musculoskeletal problems. For women, Beck depression inventory and diabetes mellitus also had positive and negative associations with musculoskeletal problems, respectively.

SES had no association with musculoskeletal problems in PD patients. Women had a higher risk of musculoskeletal problems. A gender difference was shown in the risk factors of musculoskeletal problems.

Clinical phenotypes such as old age, longer disease duration, motor disability, akineto-rigid type, dementia and hallucinations are known to be associated with REM sleep behavior disorder (RBD) in Parkinson's disease (PD). However, the relationship between motor fluctuations/impulse control and related behaviors (ICRB) and RBD is not clear. We designed this study to elucidate the clinical manifestations associated with RBD to determine the implications of RBD in PD.

In a cross-sectional study, a total of 994 patients with PD were interviewed to determine the presence of RBD and their associated clinical features including motor complications and ICRB.

Of the 944 patients, 578 (61.2%) had clinical RBD. When comparing the clinical features between patients with RBD (RBD group) and without RBD (non-RBD group), older age, longer disease duration, higher Hoehn and Yahr stage (H&Y stage), higher levodopa equivalent daily dose (LEDD), and the existence of wearing off, dyskinesia, freezing, and ICRB, especially punding, were associated with the RBD group compared to the non-RBD group (P < .05 in all). Multivariate analysis showed that motor complications including wearing off, peak dose dyskinesia, and diphasic dyskinesia were the only relevant factors for RBD after adjusting for age and disease duration.

Motor complications and ICRB are more frequent in patients with RBD than in patients without RBD. In addition, motor complications are related to RBD even after adjusting for age and disease duration.

To identify the prevalence and clinical features of musculoskeletal problems in patients with Parkinson disease (PD) compared to controls.

400 PD patients and 138 age- and sex-matched controls were interviewed by physicians about their musculoskeletal problems.

The prevalence of musculoskeletal problems was significantly higher in the PD group than in the control group (66.3% vs. 45.7%, P < 0.001). Commonly involved body sites were the low back, knee, and shoulder in that order. The low back was more frequently involved in the PD group than in the control group (44.3% vs. 24.6%, P < 0.001), and the shoulder tended to be more involved in the PD group than in the control group (15.0% vs. 8.7%, P = 0.061). However, the knee was similarly involved in both group (12.3% vs. 18.0%, P = 0.121). Among the past diagnoses associated with musculoskeletal problems, frozen shoulder, low back pain, osteoporosis and fracture were more common in the PD group than in the control group (P < 0.05). Older age, female, and a higher score on the Unified Parkinson's Disease Rating Scale I & II were associated with musculoskeletal problems in the PD group. Only 26.8% of the PD patients and 52.5% of the controls with musculoskeletal problems answered that their musculoskeletal problems were recovering. Furthermore, musculoskeletal problems in the PD group tended to receive less treatment than that of the control group (P = 0.052).

Musculoskeletal problems were more common in the PD group than in the controls. Furthermore, despite PD patients having a higher prevalence, they did not receive adequate treatment.

Parkinson's disease (PD) is a progressive neurodegenerative disease that mainly affects extrapyramidal motor function. Dopamine replacement therapy by levodopa (L-DOPA) is the best treatment for motor control. Moreover, dopamine agonists (DAs), monoamine oxidase type B (MAO-B) inhibitors, anticholinergic agents, catechol O-methyl transferase (COMT) inhibitors and amantadine are used mostly as adjuvant therapeutics. MAO-B inhibitors, especially selegiline may have potential neuroprotective effects, and anticholinergic agents play a role in tremor alleviation. Non-ergot DAs (e.g., pramipexole or ropinirole) substitute for the ergot ones (e.g., pergolide) due to having less cardiac valve problems. Initiation of either DAs or L-DOPA can be used for managing bradykinesia and rigidity in young and elderly patients, respectively. Chronic use of L-DOPA may induce motor complications, including motor fluctuations and dyskinesias in advanced PD. For reducing off time, inhibitors of COMT and/or MAO-B could be added. For reducing dyskinesias, amantadine may be considered. Pramipexole and ropinirole have been used recently as the initial treatment for young PD patients. Nonmotor symptoms (e.g., depression) are also important comorbidities in PD patients. Pramipexole and selegiline may be used in treating motor and depressive problems simultaneously in addition to their antiparkinsonian effects. All current antiparkinsonian medications alleviate merely extrapyramidal symptoms. Drugs for PD in the future should be targeting the disease progression.

To survey the point prevalence of impulse control and repetitive behavior disorders (ICRBs) in patients with Parkinson disease (PD) and to determine the relationship between PD medication dose and the risk of ICRBs.

A multicenter cross-sectional survey was applied to consecutive patients with PD over a 3-month period. The presence of ICRBs was screened using a modified version of the Minnesota Impulsive Disorders Interview that comprised five ICRB modules: compulsive buying, gambling, sexual behavior, eating, and punding. Data regarding the patients' clinical features and concurrent anti-PD drugs were also collected during the interview. Adjusted odds ratios (ORs) of the daily doses of dopamine agonist and l-dopa for the development of an ICRB were calculated after adjustment for clinical variables.

Among the 1167 patients recruited, 118 (10.1%) exhibited ICRBs. Punding was the most common ICRB (4.2%), followed by compulsive eating (3.4%), sexual behaviors (2.8%), buying (2.5%), and gambling (1.3%). Two or more ICRBs were present concomitantly in 34 of these 118 patients (28.8%). There were dose–response relationships between the dopamine agonist dose and the ORs for compulsive buying, gambling and sexual behaviors. On the other hand, the OR for punding was positively correlated with the dose of l-dopa. The OR for compulsive eating was not associated with the dose of dopamine agonist or l-dopa.

The dose of dopaminergic medication is significantly associated with the development of ICRB, except compulsive eating, in PD.