Evaluating the validity and reliability of the Korean version of Scales for Outcomes in Parkinson's Disease-Cognition.

Objective: The Scales for Outcomes in Parkinson's Disease-Cognition (SCOPA-Cog) was developed to screen for cognition in PD. In this study, we aimed to evaluate the validity and reliability of the Korean version of the SCOPA-cog. Methods: We recruited 129 PD patients from 31 clinics with movement disorders in South Korea. The original version of the SCOPA-cognition was translated into Korean using the translation-retranslation method. The test-rest method with an intraclass correlation coefficient (ICC) and Cronbach's alpha coefficient were used to assess reliability. The Spearman's Rank correlation analysis with Montreal Cognitive Assessment-Korean version (MOCA-K) and Korean Mini-Mental State Examination (K-MMSE) were used to assess concurrent validity. Results: The Cronbach's alpha coefficient was 0.797, and the ICC was 0.887. Spearman's rank correlation analysis showed a significant correlation with the K-MMSE and MOCA-K scores (r = 0.546 and r = 0.683, respectively). Conclusions: Our results demonstrate that K-SCOPA-Cog exhibits good reliability and validity.

Opicapone to Treat Early Wearing-off in Parkinson's Disease Patients: The Korean ADOPTION Trial.

BACKGROUND: Increasing levodopa (L-dopa)/dopa decarboxylase inhibitor (DDCI) daily dose or adding a catechol-O-methyltransferase (COMT) inhibitor to levodopa/DDCI therapy are strategies used to manage wearing-off symptoms in Parkinson's disease (PD) patients. OBJECTIVES: To evaluate the COMT inhibitor opicapone versus an additional dose of levodopa to treat early wearing-off in PD patients. METHODS: ADOPTION was a randomized, parallel-group, open-label, Phase 4 study conducted in Korea. At baseline, eligible patients were randomized (1:1) to opicapone 50 mg (n = 87) or L-dopa 100 mg (n = 81) (added to current L-dopa/DDCI therapy) for 4 weeks. The main efficacy endpoint was change from baseline to end of study in absolute off time. Other endpoints included changes in on time, in Movement Disorder Society-Unified Parkinson's Disease Rating Scale and 8-item PD Questionnaire scores, and the Clinical and Patient Global Impression of Improvement/Change. RESULTS: The adjusted mean in absolute off time was significantly greater for opicapone 50 mg than for L-dopa 100 mg (-62.1 vs. -16.7 minutes; P = 0.0015). Opicapone-treated patients also reported a greater reduction in the percentage of off time (P = 0.0015), a greater increase in absolute on time (P = 0.0338) and a greater increase in the percentage of on time (P = 0.0015). There were no significant differences in other secondary endpoints. The L-dopa equivalent daily dose was significantly higher in the opicapone group (750.9 vs. 690.0 mg; P = 0.0247), when a 0.5 conversion factor is applied. CONCLUSIONS: Opicapone 50 mg was more effective than an additional 100 mg L-dopa dose at decreasing off time in patients with PD and early wearing-off.

More than autophony: a case of Kennedy's disease presenting with autophony as an early clinical manifestation.

BACKGROUND: As autophony can be accompanied by several conditions, it is important to find co-morbidities. This paper reports a patient with Kennedy's disease (spinobulbar muscular atrophy, an X-linked, hereditary, lower motor neuron disease) having autophony as the first symptom. CASE REPORT: A 62-year-old male presented to the otorhinolaryngology department with autophony that began 2 years previously and worsened after losing weight 3 months prior to presentation. Otoscopic examination demonstrated inward and outward movement of the tympanic membrane, synchronised with respiration. Although he had no other symptoms, facial twitching was found on physical examination. In the neurology department, lower motor neuron disease, with subtle weakness of the tongue, face and upper limbs, and gynaecomastia, were confirmed. He was diagnosed with Kennedy's disease based on genetic analysis. CONCLUSION: Autophonia was presumed to be attributed to bulbofacial muscle weakness due to Kennedy's disease, and worsened by recent weight loss. Patients with autophony require a thorough history-taking and complete physical examination to assess the nasopharynx and the integrity of lower cranial function.

Combination effects of herbal and western medicines on osteoporosis in rheumatoid arthritis: systematic review and meta-analysis.

Purpose: This study aimed to comprehensively review the effect of combining herbal medicine (HM) with Western Medicine (WM) compared to WM alone on bone mineral density (BMD) improvement for osteoporosis in patients with rheumatoid arthritis (RA). Methods: Randomized controlled trials (RCTs) were searched using 10 databases, including PubMed, Embase, Cochrane Library, China National Knowledge Infrastructure, and Nation Information by NII. We selected studies that used BMD as an evaluation index and administered HM treatment for osteoporosis in patients with RA. Subsequently, a meta-analysis was conducted using BMD as a continuous variable using RevMan version 5.4. Results: Eighteen RCTs that met the eligibility criteria of this study were selected. The total number of study participants was 1,491 (481 men and 1,010 women). The mean age of participants was 52.4 ± 7.4 years, and the mean morbidity period of RA was 6.8 ± 1.3 years. In all studies, disease-modifying anti-rheumatic drugs (DMARDs; 16 RCTs) or bisphosphonates (two RCTs) were used as WM co-intervention with HMs (17 types of HM, 18 RCTs). Overall, the combination of HM and WM improved the BMD score, producing better results than WM alone. In particular, when HM was used in combination with DMARDs, which were used in most studies, BMD improved by 0.04 g/cm2 (95% confidence interval [CI]: 0.03-0.05, p < 0.001, I2 = 19%) in the lumbar spine and 0.03 g/cm2 (95% CI: 0.02-0.03, p < 0.001, I2 = 0%) in the femoral neck compared to the DMARDs alone group after treatment. In addition to BMD, bone markers and inflammatory indicators evaluated by each RCT showed significant improvement after HM plus WM treatment. In the analysis of frequently prescribed HMs, the BMD after treatment was higher by 0.04 g/cm2 (95% CI: 0.03-0.04, p < 0.001, I2 = 45%) in the Xianlinggubao-capsule plus methotrexate (MTX) group and by 0.02 g/cm2 (95% CI: 0.00-0.03, p = 0.04, I2 = 0) in the Hanbikang-tang plus MTX group compared to the MTX alone group. Conclusion: This systematic review cautiously provides evidence for the combined therapeutic effect of HM and WM for osteoporosis in patients with RA. However, well-designed, large-scale clinical trials are necessary before recommending this combination therapy for osteoporosis in patients with RA. Systematic Review Registration: [https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=331854], identifier [CRD42022331854].

Quantitative Analysis of Postural Balance in Faller and Nonfaller Patients with Parkinson's Disease.

Background: Postural instability has been identified as a fall risk factor with a significant impact on the quality of life of patients with Parkinson's disease (PD). The aim of this study was to compare the center of pressure (COP) between faller and nonfaller patients with PD during static standing. Methods: Thirty-two faller patients and 32 nonfaller patients with PD participated in this study. All patients performed the static balance test on a force plate. COP data were recorded during quiet standing. Mean distance, sway area, mean velocity, mean frequency, and peak power were derived from the COP data. Statistical analysis was performed using independent t-tests to compare faller and nonfaller patients. Results: Fallers presented a greater average distance, wider sway area, faster average speed, and greater peak power than nonfallers (p < 0.05). In contrast, no significant group differences were observed in peak frequency and mean frequency (p > 0.05). Conclusions: Although falls occur during dynamic activities, our study demonstrated that even a safe and simple static postural balance test could significantly differentiate between faller and nonfaller patients. Thus, these results suggest that quantitatively assessed static postural sway variables would be useful for distinguishing prospective fallers among PD patients.

Comparison of resting tremor at the upper limb joints between patients with Parkinson's disease and scans without evidence of dopaminergic deficit.

BACKGROUND: A representative symptom of Parkinson's disease (PD) is resting tremor. The clinical manifestation of scans without evidence of dopaminergic deficit (SWEDD) is similar to it of PD, though the phenomenology of SWEDD is not well known. OBJECTIVE: In the present study, the resting tremor of 9 SWEDD patients was quantitatively compared with that of 11 PD patients. METHODS: Four 3-axis gyro sensors were attached on the index finger, thumb, dorsum of the hand, and arm of the more tremulous side. Root mean square (RMS) angular speed and angular displacement as well as irregularity of angular speed and displacement were derived from the sensor data. RESULTS: Although disease duration and Hoehn and Yahr stages were comparable, SWEDD patients exhibited different tremor features from PD patients. Significantly faster RMS angular speed and greater RMS angular displacement (p< 0.05) were observed in PD patients than in SWEDD patients. The irregularity of angular displacement of pitch direction at the dorsum of the hand was greater in SWEDD patients than in PD patients (p< 0.05). CONCLUSION: These results indicate that quantitative indices obtained from resting tremor task could be important biomarkers for identifying potential patients with SWEDD among patients diagnosed with PD.

Incidence Rate of Bee Venom Acupuncture Related Anaphylaxis: A Systematic Review.

BACKGROUND: Bee venom acupuncture (BVA) is an effective treatment method for various diseases. Bee venom, however, can cause adverse effects, even rarely including life-threatening anaphylaxis, so safety-related evidence is required. In this study, we systematically estimated the incidence rate of anaphylaxis in response to BVA. METHODS: We searched eight databases (MEDLINE (Pubmed), EMBASE, Cochrane Central Register of Controlled, KISS, KMBASE, Koreamed, OASIS, and NDSL) and systematically reviewed the articles that met the inclusion/exclusion criteria. RESULTS: Among 225 potentially relevant articles, 49 were selected for this study. The overall incidence rate of anaphylaxis in response to BVA was 0.045% (95% CI 0.028-0.062). Women (0.083%, 95% CI 0.010-0.157) showed a higher incidence rate than men (0.019%, 95% CI -0.018 to 0.055), while the incidence for patients who had a skin test conducted (0.041%, 95% CI 0.011-0.072) was not significantly different compared to that obtained for patients for which there was no information about a skin test (0.047%, 95% CI 0.026-0.067). The publication year affected the incidence rate: it was highest before 1999 (1.099%, 95% CI -1.043 to 3.241), lower between 2000 and 2009 (0.049%, 95% CI 0.025-0.073), and lowest between 2010 and 2021 (0.037% 95% CI 0.014-0.060). CONCLUSIONS: In this study, we provide reference data about risk size and factors of BVA-related anaphylaxis, which is essentially required for BVA application in clinics.

A prospective multi-centre study of susceptibility map-weighted MRI for the diagnosis of neurodegenerative parkinsonism.

OBJECTIVES: This study aimed to compare susceptibility map-weighted imaging (SMwI) using various MRI machines (three vendors) with N-3-fluoropropyl-2-ß-carbomethoxy-3-ß-(4-iodophe nyl)nortropane (18F-FP-CIT) PET in the diagnosis of neurodegenerative parkinsonism in a multi-centre setting. METHODS: We prospectively recruited 257 subjects, including 157 patients with neurodegenerative parkinsonism, 54 patients with non-neurodegenerative parkinsonism, and 46 healthy subjects from 10 hospitals between November 2019 and October 2020. All participants underwent both SMwI and 18F-FP-CIT PET. SMwI was interpreted by two independent reviewers for the presence or absence of abnormalities in nigrosome 1, and discrepancies were resolved by consensus. 18F-FP-CIT PET was used as the reference standard. Inter-observer agreement was tested using Cohen's kappa coefficient. McNemar's test was used to test the agreement between the interpretations of SMwI and 18F-FP-CIT PET per participant and substantia nigra (SN). RESULTS: The inter-observer agreement was 0.924 and 0.942 per SN and participant, respectively. The diagnostic sensitivity of SMwI was 97.9% and 99.4% per SN and participant, respectively; its specificity was 95.9% and 95.2%, respectively, and its accuracy was 97.1% and 97.7%, respectively. There was no significant difference between the results of SMwI and 18F-FP-CIT PET (p > 0.05, for both SN and participant). CONCLUSIONS: This study demonstrated that the high diagnostic performance of SMwI was maintained in a multi-centre setting with various MRI scanners, suggesting the generalisability of SMwI for determining nigrostriatal degeneration in patients with parkinsonism. KEY POINTS: • Susceptibility map-weighted imaging helps clinicians to predict nigrostriatal degeneration. • The protocol for susceptibility map-weighted imaging can be standardised across MRI vendors. • Susceptibility map-weighted imaging showed diagnostic performance comparable to that of dopamine transporter PET in a multi-centre setting with various MRI scanners.

Hardening Properties of Cheeses by Latilactobacillus curvatus PD1 Isolated from Hardened Cheese-Ddukbokki Rice Cake.

Hardening of cheese is one of major issues that degrade the quality of Home Meal Replacement (HMR) foods containing cheese such as Cheese-ddukbokki rice cake (CD, stir-fried rice cakes with shredded cheese). The quality of cheese, such as pH, proteolytic, and flavor properties, depends on various lactic acid bacteria (LAB) used in cheese fermentation. The hardening of cheese is also caused by LAB. In this study, various LAB strains were isolated from CD samples that showed rapid hardening. The correlation of LAB with the hardening of cheese was investigated. Seven of the CD samples with different manufacturing dates were collected and tested for hardening properties of cheese. Among them, strong-hardening of cheese was confirmed for two samples and weak-hardening was confirmed for one sample. All LAB in two strong-hardening samples and 40% of LAB in one weak-hardening sample were identified as Latilactobacilluscurvatus. On the other hand, most LAB in normal cheese samples were identified as Leuconostoc mesenteroides and Lactobacillus casei. We prepared cheese samples in which L. curvatus (LC-CD) and L. mesenteroides (LM-CD) were most dominant, respectively. Each CD made of the prepared cheese was subjected to quality test for 50 days at 10 °C. Hardening of cheese with LC-CD dominant appeared at 30 days. However, hardening of cheese with LM-CD dominant did not appear until 50 days. The pH of the LC-CD was 5.18 ± 0.04 at 30 days, lower than that of LM-CD. The proteolytic activity of LC-CD sample was 2993.67 ± 246.17 units/g, higher than that of LM-CD sample (1421.67 ± 174.5 units/g). These results indicate that high acid production and high protease activity of L. curvatus might have caused hardening of cheese.

Association of High-Density Lipoprotein Cholesterol Variability and the Risk of Developing Parkinson Disease.

OBJECTIVE: To investigate the longitudinal association among high-density lipoprotein cholesterol (HDL-C) level, HDL-C variability, and the risk of developing Parkinson disease (PD). METHODS: We conducted a nationwide, population-based cohort study. We included 382,391 patients aged ≥65 years who underwent at least 3 health examinations provided by the Korean National Health Insurance System from 2008 to 2013 and followed up until 2017. Individuals with a history of PD and missing values were excluded (n = 1,987). We assessed HDL-C variability using 3 indices, including variability independent of the mean (VIM). A multivariate-adjusted Cox proportional hazards regression analysis was performed. RESULTS: Among the 380,404 participants, 2,733 individuals were newly diagnosed with PD during a median follow-up period of 5 years. The lowest quartile (Q1) group of baseline HDL-C and mean HDL-C was associated with increased PD incidence as compared with the highest quartile (Q4) group (adjusted hazard ratio [aHR], 1.20; 95% confidence interval [CI], 1.08-1.34; and aHR, 1.16; 95% CI, 1.04-1.30, respectively). The Q4 group of HDL-C variability (VIM) was associated with increased PD incidence compared to the Q1 group (aHR, 1.19; 95% CI, 1.06-1.33). The group with the Q1 of baseline HDL-C and with the Q4 of HDL-C variability had the highest risk of PD incidence (aHR, 1.6; 95% CI, 1.31-1.96). CONCLUSION: Lower HDL-C level and greater HDL-C variability were associated with a higher incidence of PD.

Post-Stroke Depressive Symptoms: Varying Responses to Escitalopram by Individual Symptoms and Lesion Location.

OBJECTIVE: The efficacy of antidepressants in post-stroke depressive symptoms (PSD) varies. We aimed to examine whether the effect of escitalopram on PSD differs according to individual depressive symptoms and stroke lesion location. METHODS: This is a post hoc analysis of EMOTION (ClinicalTrials.gov, NCT01278498), a randomized, placebo-controlled, double-blind trial that examined the efficacy of escitalopram on depression in acute stroke patients (237 with placebo, 241 with escitalopram). Depressive symptoms were evaluated with the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS). Changes in MADRS and individual item scores at 12 weeks were compared between the treatment groups and among the stroke lesion location groups. Stroke lesion locations were grouped according to the anatomical distribution of serotonin fibers that originate from the midbrain/pons and spread to the forebrain via subcortical structures: "Midbrain-Pons," "Frontal-Subcortical," and "Others." Least-squares means were calculated to demonstrate the independent effect of lesion location. RESULTS: Total MADRS scores decreased more significantly in the escitalopram than in the placebo group, while a significant effect of escitalopram was observed in only 3 items: apparent sadness, reported sadness, pessimistic thoughts. In the lesion location analyses, escitalopram users in the Frontal-Subcortical group showed significant improvement in total MADRS scores (placebo [n = 130] vs. escitalopram [n = 148], least-square mean [95% CI]: -2.3 [-3.5 to -0.2] vs. -4.5 [-5.5 to -3.4], p = .005), while those in the Midbrain-Pons and Others groups did not. CONCLUSIONS: The effect of escitalopram on PSD may be more prominent in patients with particular depressive symptoms and stroke lesion locations, suggesting the need for tailored treatment strategies.

Quantitative measures of postural tremor at the upper limb joints in patients with essential tremor.

BACKGROUND: It is important to quantitatively assess tremor for accurate diagnosis and evaluation of the response to interventions in patients with essential tremor (ET). OBJECTIVE: The purpose of this study was to investigate the relationship between quantitative measures of postural tremor and clinical rating scale in patients with ET. METHODS: 18 ET patients performed a postural tremor task that required them to hold their arms outstretched parallel to the floor while wearing a gyro sensor based measurement system. The time domain variables were derived from the sensor signals. Additionally, the frequency domain variables were derived from the power spectrum of the angular velocity signal. Spearman correlation analysis was employed in the relationship between the variables and clinical score. RESULTS: The RMS angular velocity of roll and yaw directions at the hand joint were strongly correlated with the clinical rating scale (r= 0.7, p< 0.01). Similarly, the peak power of roll and yaw directions at the hand joint were moderately correlated with the clinical rating scale (r= 0.61 and r= 0.67, p< 0.01). In contrast, no significant correlation coefficients were observed in the peak frequency (p> 0.05). CONCLUSION: These results indicate that hand tremor of roll and yaw directions are more associated with assessment of severity of ET compared to other joints. This study suggests that quantitative measurements of postural tremor should be considered as tremor directionality as well as attachment location.

Validation of the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale.

BACKGROUND AND PURPOSE: Impulse-control disorder is an important nonmotor symptom of Parkinson's disease (PD) that can lead to financial and social problems, and be related to a poor quality of life. A nationwide multicenter prospective study was performed with the aim of validating the Korean Version of the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease Rating Scale (K-QUIP-RS). METHODS: The K-QUIP-RS was constructed using forward and backward translation, and pretesting of the prefinal version. PD patients on stable medical condition were recruited from 27 movement-disorder clinics. Participants were assessed using the K-QUIP-RS and evaluated for parkinsonian motor and nonmotor statuses and for PD-related quality of life using a predefined evaluation battery. The test-retest reliability of the K-QUIP-RS was assessed over an interval of 10-14 days, and correlations between the KQUIP-RS and other clinical scales were analyzed. RESULTS: This study enrolled 136 patients. The internal consistency of the K-QUIP-RS was indicated by a Cronbach's α coefficient of 0.846, as was the test-retest reliability by a Guttman split-half coefficient of 0.808. The total K-QUIP-RS score was positively correlated with the scores for depression and motivation items on the Unified PD Rating Scale (UPDRS), Montgomery-Asberg Depression Scale, and Rapid-Eye-Movement Sleep-Behavior-Disorders Questionnaire. The total K-QUIP-RS score was also correlated with the scores on part II of the UPDRS and the PD Quality of Life-39 questionnaire, and the dopaminergic medication dose. CONCLUSIONS: The K-QUIP-RS appears to be a reliable assessment tool for impulse-control and related behavioral disturbances in the Korean PD population.

Isolation and Characterization of Kimchi Starters Leuconostoc mesenteroides PBio03 and Leuconostoc mesenteroides PBio104 for Manufacture of Commercial Kimchi.

This study was focused on developing and obtaining a kimchi starter for use in commercial kimchi production. Kimchi varieties made with selected starters are of high quality, have high levels of mannitol, and extended shelf life. The starters were screened for properties such as mannitol production, low gas/acid production, and acid resistance. Finally, kimchi fermentation testing was performed using selected LAB starters. Kimchi samples were prepared with lactic acid bacteria (LAB) starters, including Leuconostoc mesenteroides PBio03 and Leuconostoc mesenteroides PBio104. The LAB starters are isolated from kimchi and can grow under pH 3.0 and low temperature conditions of 5°C. Four kimchi samples were fermented and stored for 28 days at 5°C. The kimchi samples made with starters (PBio03 and PBio104) had better quality (production of mannitol and maintenance of heterofermentative LAB dominance) than the non-starter kimchi samples. In the starter kimchi, Leu. mesenteroides was the dominant LAB, comprising 80% and 70% of total LAB counts at 7 and 21 days, respectively. Mannitol content of the kimchi with Leu. mesenteroides PBio03 was 1,423 ± 19.1 mg/ 100 g at 28 days, which was higher than that of the non-starter kimchi sample (1,027 ± 12.2 mg/100 g). These results show the possibility of producing kimchi with improved qualities using Leu. mesenteroides PBio03 and PBio104 as starters.

Depressive Symptoms in Stroke Patients: Are There Sex Differences?

BACKGROUND: We aimed to examine sex differences in symptom characteristics and pharmacological responses in post-stroke depressive (PSD) symptoms. METHODS: This is a post hoc analysis of EMOTION (ClinicalTrials.gov, NCT01278498), a randomized, placebo-controlled, double-blind trial that examined the efficacy of escitalopram for 3 months on depression in patients with acute stroke. Depressive symptoms were evaluated using the 10-item Montgomery-Åsberg Depression Rating Scale (MADRS). Baseline characteristics, clinical variables, and treatment responses to escitalopram were compared between male and female patients. Treatment responses were defined as changes in MADRS (total score and its components) between baseline and 3 months and were compared between the escitalopram and placebo groups within each sex group. The least square mean was calculated to determine the independent effect of escitalopram, of which interaction was evaluated with patient sex. RESULTS: Of the 478 patients (intention-to-treat population), 187 (39%) were female. Female patients were significantly older than male patients and demonstrated more severe depressive symptoms at baseline (male vs. female, MADRS score, mean [SD]: 9.7 ± 8.0 vs. 12.2 ± 8.4, p = 0.001), especially in apparent sadness, reported sadness, and reduced appetite items. These differences were significant after adjustment for age and the severity of neurologic deficits. The female escitalopram group showed a significant 3-month improvement in MADRS scores (placebo [n = 86] vs. escitalopram [n = 101], least square mean [95% CI] -2.7 [-4.1 to -1.2] vs. -5.0 [-6.4 to -3.6], p = 0.007), and this efficacy was prominent in apparent sadness, reported sadness, and pessimistic thoughts items. However, there was no significant effect of escitalopram on depressive symptoms in the male group. The treatment responses of escitalopram tended to be more pronounced in the female group, particularly in alleviating a subset of depressive symptoms such as apparent sadness (p for interaction = 0.009). CONCLUSION: PSD may differ according to sex in its symptom characteristics and treatment responses to escitalopram, and tailored treatment strategies for PSD may therefore be needed.

Subtypes of Sleep Disturbance in Parkinson's Disease Based on the Cross-Culturally Validated Korean Version of Parkinson's Disease Sleep Scale-2.

BACKGROUND AND PURPOSE: This study aimed to determine the clinimetric properties of the Korean version of Parkinson's Disease Sleep Scale-2 (K-PDSS-2) and whether distinct subtypes of sleep disturbance can be empirically identified in patients with Parkinson's disease (PD) using the cross-culturally validated K-PDSS-2. METHODS: The internal consistency, test-retest reliability, scale precision, and convergent validity of K-PDSS-2 were assessed in a nationwide, multicenter study of 122 patients with PD. Latent class analysis (LCA) was used to derive subgroups of patients who experienced similar patterns of sleep-related problems and nocturnal disabilities. RESULTS: The total K-PDSS-2 score was 11.67±9.87 (mean±standard deviation) at baseline and 12.61±11.17 at the retest. Cronbach's α coefficients of the total K-PDSS-2 scores at baseline and follow-up were 0.851 and 0.880, respectively. The intraclass correlation coefficients over the 2-week study period ranged from 0.672 to 0.848. The total K-PDSS-2 score was strongly correlated with health-related quality of life measures and other corresponding nonmotor scales. LCA revealed three distinct subtypes of sleep disturbance in the study patients: "less-troubled sleepers," "PD-related nocturnal difficulties," and "disturbed sleepers." CONCLUSIONS: K-PDSS-2 showed good clinimetric attributes in accordance with previous studies that employed the original version of the PDSS-2, therefore confirming the cross-cultural usefulness of the scale. This study has further documented the first application of an LCA approach for identifying subtypes of sleep disturbance in patients with PD.

Facial Expression Processing Is Not Affected by Parkinson's Disease, but by Age-Related Factors.

The question whether facial expression processing may be impaired in Parkinson's disease (PD) patients so far has yielded equivocal results - existing studies, however, have focused on testing expression processing in recognition tasks with static images of six standard, emotional facial expressions. Given that non-verbal communication contains both emotional and non-emotional, conversational expressions and that input to the brain is usually dynamic, here we address the question of potential facial expression processing differences in a novel format: we test a range of conversational and emotional, dynamic facial expressions in three groups - PD patients (n = 20), age- and education-matched older healthy controls (n = 20), and younger adult healthy controls (n = 20). This setup allows us to address both effects of PD and age-related differences. We employed a rating task for all groups in which 12 rating dimensions were used to assess evaluative processing of 27 expression videos from six different actors. We found that ratings overall were consistent across groups with several rating dimensions (such as arousal or outgoingness) having a strong correlation with the expressions' motion energy content as measured by optic flow analysis. Most importantly, we found that the PD group did not differ in any rating dimension from the older healthy control group (HCG), indicating highly similar evaluation processing. Both older groups, however, did show significant differences for several rating scales in comparison with the younger adults HCG. Looking more closely, older participants rated negative expressions compared to the younger participants as more positive, but also as less natural, persuasive, empathic, and sincere. We interpret these findings in the context of the positivity effect and in-group processing advantages. Overall, our findings do not support strong processing deficits due to PD, but rather point to age-related differences in facial expression processing.