Seong-Beom Koh

The Role of Cognitive Function in Complex Gait Patterns

Objective Cognitive impairment is common in patients with Parkinson’s disease (PD), and few pharmacological options are available for treating this condition. We evaluated the effects of a digital cognitive training program (SUPERBRAIN), which was previously shown to be effective in populations at risk of Alzheimer’s disease, on cognitive function in individuals with PD.Methods Twenty-three individuals with PD and mild cognitive impairment (PD-MCI) from four clinics were randomized to the intervention (n=16) or control (n=7) groups. The intervention group completed a 12-week, home-based, tablet-based cognitive training program (25–30 min/day, 7 days/week). Cognitive outcomes were assessed using the Seoul Neuropsychological Screening Battery pre- and post-intervention.Results The adherence rate was 79.36%. The intervention group showed significant improvements in the Seoul Verbal Learning Test (SVLT) delayed recall and the Controlled Oral Word Association Test, while no changes were observed in the control group. Analysis of covariance confirmed greater SVLT improvement in the intervention group (F statistic=7.15, p=0.015, partial η2=0.28).Conclusion SUPERBRAIN is feasible and can improve cognitive function in individuals with PD-MCI.

Purpose Autonomic dysfunction, including early cardiovascular parasympathetic involvement, is sustained throughout Parkinson’s disease (PD). The vagus nerve, shown by ultrasonography, is atrophic in PD patients. We examined vagus nerve cross-sectional area (CSA) in controls versus PD patients, and its association with autonomic function in early PD. Methods We investigated 118 de novo PD patients and 29 controls. Vagus nerve CSA was measured using nerve ultrasonography at the bilateral mid-cervical area. Each patient was evaluated once by a randomly assigned sonographer; each control was measured twice by both. For accurate comparison, patients with diabetes were additionally excluded from the PD group. A 1:1 propensity score matching based on age, sex, hypertension, and dyslipidemia was performed. The CSA was compared between matched patients and controls. Clinical interviews, rating scales, and autonomic and olfactory function tests were performed. The association between these results and the CSA was analyzed. Results Median right and left vagus nerve CSA measured 1.3 and 1.2 mm², respectively, significantly lower than in controls (2.3 and 2.2 mm²). Partial correlation analysis showed a negative correlation between the right vagus CSA and abnormal heart rate response to deep breathing (rho = −0.191, P = 0.045). Conclusion Small right vagus nerve CSA is associated with early parasympathetic dysfunction in PD patients. These findings support the use of vagus nerve ultrasound as a potential non-invasive biomarker for identifying prodromal autonomic involvement and informing future early intervention research.

Parkinson's disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. While PD is typically characterized by motor symptoms such as bradykinesia, tremor, rigidity, postural instability, and gait disturbances, patients frequently present numerous non-motor symptoms, including gastrointestinal manifestations. These gastrointestinal symptoms may be fundamentally related to alpha-synuclein pathology, and dopaminergic treatments may further contribute to reduced gastrointestinal motility. Gastrointestinal symptoms can occur before the diagnosis of PD and at any stage during the disease course, affecting the gastrointestinal tract from the oral cavity to the anus. If left untreated, gastrointestinal problems can impair medication absorption, leading to motor fluctuations and potentially causing complications such as malnutrition and aspiration pneumonia, which may be life-threatening. Therefore, clinicians should not overlook gastrointestinal symptoms in PD patients. Gastrointestinal symptoms in PD can manifest diversely throughout the entire disease course, requiring healthcare providers to recognize these symptoms and provide individualized management. Since current treatments for PD-related gastrointestinal symptoms are largely derived from data in non-PD patients, future research and clinical guideline development in this field are required for establishing evidence-based care protocols.

Objective and quantitative evaluation of the gait has a very important implications in patients with neurological disorders. Such evaluation is possible by gait analysis system and can be clinically useful. Gait analysis can be performed through laboratory systems, non-wearable sensors, and/or wearable sensors. Using this system, neurologists can measure objective evaluation and treatment effects in patients with movement disorders, including Parkinson's disease, normal pressure hydrocephalus, stroke, Alzheimer's disease, and normal aging. In this review, we aimed to introduce the currently available gait analysis systems, and also present what you need to know in clinical applications.

Background: Various comorbidities contribute to mortality in patients with Parkinson’s disease (PD). Although growing evidence demonstrates that chronic kidney disease (CKD) increases the risk of developing PD, the effect of CKD on all-cause mortality remains unclear. Methods: We enrolled 59,293 patients aged ≥40 years with de novo PD between 2009 and 2015, using de-identified data from the Korean National Health Insurance Service. Cox proportional hazards regression analysis using the presence of CKD or proteinuria as a predictor was performed to investigate the association between CKD, proteinuria, and mortality. For sensitivity analysis, the degree of eGFR or proteinuria were used as predictors in place of CKD/proteinuria. Results: Parkinson’s disease patients with CKD (hazard ratio [HR] = 1.240, 95% confidence interval [CI] 1.190–1.283) and proteinuria (HR = 1.543, 95% CI 1.457–1.634) had a higher risk of mortality, even after controlling for confounding factors. The degree of kidney dysfunction ( p < 0.001) and proteinuria ( p < 0.001) were associated with an increased HR for mortality. Furthermore, female patients with CKD were more vulnerable to mortality than male patients ( p for sex × CKD < 0.001); however, there was no sex-specific vulnerability of proteinuria to mortality ( p for sex × proteinuria = 0.603). Conclusion: Chronic kidney disease and proteinuria were associated with a higher all-cause mortality in patients with PD in a dose-dependent manner. Furthermore, these results highlight that strategies for controlling kidney function are necessary to reduce mortality in patients with PD.

This review provides a comprehensive framework for the diagnostic approach and management of Huntington’s disease (HD) tailored to the Korean population. Key topics include genetic counseling, predictive testing, and reproductive options like preimplantation genetic testing. Strategies for assessing disease progression in premanifest HD through laboratory investigations, biofluid, and imaging biomarkers are highlighted. Special considerations for juvenile and late-onset HD, along with associated comorbidities like diabetes mellitus, hypertension, and cardiovascular abnormalities, are discussed. The guide emphasizes personalized symptom management, including pharmacotherapy, physical therapy, and nutritional support, while exploring emerging disease-modifying treatments. A multidisciplinary care model is advocated to improve outcomes for HD patients and caregivers in Korea.

Objective We conducted this study to assess the efficacy and safety of taltirelin hydrate (TH) in patients with ataxia due to spinocerebellar degeneration (SCD).Methods Patients were randomly assigned to either the taltirelin group (5 mg orally, twice daily) or the control group. The primary endpoint was the change in the Korean version of the Scale for the Assessment and Rating of Ataxia (K-SARA) score at 24 weeks. The secondary endpoints included changes in the K-SARA score at 4 and 12 weeks as well as the Clinical Global Impression Scale, the five-level version of the EuroQol five-dimensional questionnaire, the Tinetti balance test, and gait analysis at 4, 12, and 24 weeks.Results A total of 149 patients (hereditary:nonhereditary=86:63) were enrolled. There were significant differences in the change in the K-SARA score at 24 weeks from baseline between the taltirelin group and the control group (-0.51±2.79 versus 0.36±2.62, respectively; p=0.0321). For the K-SARA items, the taltirelin group had significantly lower “Stance” and “Speech disturbance” subscores than the control group (-0.04±0.89 versus 0.23±0.79 and -0.07±0.74 versus 0.18±0.67; p=0.0270 and 0.0130, respectively). However, there were no significant differences in changes in other secondary efficacy outcome measures at 24 weeks from baseline between the two treatment arms (p>0.05).Conclusion Clinicians might consider the use of TH in the treatment of patients with ataxia due to SCD.

Background: Visual dysfunction, including abnormal stereopsis, is a significant non-motor symptom in Parkinson’s disease (PD) that can reduce quality of life and appears early in the disease. Abnormal stereopsis is associated with worsening of bradykinesia and freezing of gait, though the exact pathways linking stereopsis to motor symptoms remain unclear. Furthermore, in PD patients, the pedunculopontine nucleus and laterodorsal tegmental complex play an active role in sensorimotor control, and these areas provide cholinergic projections. Cholinergic degeneration may be associated with symptoms such as abnormal stereopsis, postural instability, gait disturbances and cognitive impairment. Therefore, in this study, we hypothesized that a high postural instability and gait disturbance score would increase the risk of abnormal stereopsis in PD. Methods: We designed a cross-sectional study and included 240 early PD patients without ophthalmologic problems other than abnormal stereopsis. To evaluate stereopsis, we used Titmus stereo test plates. Stereopsis testing was performed only once at the time of the patient’s initial PD diagnosis. We collected data from medical history taking, scales, cognitive function tests, gait analysis, and tilt table tests. To analyze the potential risk factors for abnormal stereopsis in PD, we conducted a binary logistic stepwise selection analysis. Results: Among the total of 240 PD patients, 185 were in the normal stereopsis group and 55 were in the abnormal stereopsis group. In the analysis for risk factors related to abnormal stereopsis, the postural instability and gait difficulties (PIGD) subtype score was significantly associated with abnormal stereopsis. (95% confidence interval: 1.37–5.15). Conclusions: In PD, particularly in PIGD subtype patients, abnormal stereopsis can lead to a decrease in the quality of sensory information, potentially interfering with feedback and adaptation processes. This, in turn, can negatively affect posture and gait, creating a vicious cycle.

Background: Whether body weight changes are associated with Parkinson’s disease (PD) mortality remains uncertain. Objective: To investigate the association between changes in body mass index (BMI) and all-cause mortality in patients with PD. Methods: This nationwide cohort study enrolled 20,703 individuals with new-onset PD (ICD-10 code: G20 and a rare intractable disease registration code: V124) who underwent health screening program by the Korean National Health Insurance Service within two years from pre- and post-PD diagnosis. We identified nine BMI change groups based on three BMI status: underweight (BMI < 18.5 kg/m²), normal or overweight (18.5 kg/m²≤BMI < 25 kg/m²), and obese (BMI≥25 kg/m²). Results: Of 20,703 individuals, 3,789 (18.0%) died during the follow-up period. Excessive weight loss to underweight in the obese group (hazard ratio [HR] = 3.36, 95% CI:1.60–7.08), weight loss in the normal to overweight group (HR = 2.04, 95% CI:1.75–2.39), sustained underweight status (HR = 2.05, 95% CI:1.67–2.52), and weight gain from underweight to normal or overweight (HR = 1.52, 95% CI:1.15–2.02) were associated with increased mortality. Sustained obese status (HR = 0.80, 95% CI:0.74–0.87) and weight gain in the normal to overweight group (HR = 0.82, 95% CI:0.71–0.95) were associated with reduced mortality. Conclusions: We found that BMI change at diagnosis was associated with mortality in patients with PD. Specifically, being underweight either before or after diagnosis as well as experiencing weight loss, were associated with increased mortality. These findings provide valuable insights for weight management planning in PD, highlighting the importance of individualized approach that consider pre-diagnosis BMI.