Effectiveness of Extracorporeal Shock Wave Therapy after Botulinum Toxin Injection for Post-Stroke Upper Extremity Spasticity: A Randomized Controlled Study.

Post-stroke spasticity is a common complication that limits the functional performance of patients. Botulinum toxin (BTx) is an effective treatment for spasticity. Numerous researchers have applied extracorporeal shock wave therapy (ESWT) to address post-stroke spasticity, yielding positive clinical outcomes. We aimed to clarify the add-on effects of ESWT on BTx therapy for spasticity in patients with post-stroke. Sixteen eligible patients with upper extremity spasticity after stroke were recruited for this study. They were randomized to either a BTx with focused ESWT treatment group or a BTx alone group. Spasticity, measured using the modified Ashworth score (MAS) and modified Tardieu scale (MTS), showed statistically significant improvements in the elbow and wrist flexor muscles in both BTx + ESWT group and BTx alone groups. However, no significant differences were observed between the two groups with time flow. The BTx + ESWT group showed significantly decreased MAS of the finger flexors at follow-up and increased R1 (MTS) of the finger flexors at 3 weeks after treatment, which was not observed in the BTx alone group. This is the first study to identify the add-on effect of ESWT on BTx injections to improve post-stroke upper limb spasticity.

Different risks of early-onset and late-onset Parkinson disease in individuals with mental illness.

We aimed to investigate the association of various mental illnesses, including depression, bipolar disorder, schizophrenia, insomnia, and anxiety, with the risk of early-onset Parkinson's disease (EOPD) (age <50 years) and compare it with that of late-onset PD (LOPD) (age ≥50 years). This nationwide cohort study enrolled 9,920,522 people who underwent a national health screening examination in 2009, and followed up until 31 December 2018. There was a significantly increased risk of EOPD and LOPD in individuals with mental illness, and EOPD showed a stronger association than LOPD (EOPD, hazard ratio (HR) = 3.11, 95% CI: 2.61‒3.72; LOPD, HR = 1.70, 95% CI: 1.66‒1.74; p for interaction <0.0001). Our results suggest that people with mental illnesses aged < 50 years are at a higher risk of PD than those aged ≥50 years. Future studies are warranted to elucidate the pathomechanism of EOPD in relation to mental illness.

Automatic Assessment of Upper Extremity Function and Mobile Application for Self-Administered Stroke Rehabilitation.

Rehabilitation training is essential for a successful recovery of upper extremity function after stroke. Training programs are typically conducted in hospitals or rehabilitation centers, supervised by specialized medical professionals. However, frequent visits to hospitals can be burdensome for stroke patients with limited mobility. We consider a self-administered rehabilitation system based on a mobile application in which patients can periodically upload videos of themselves performing reach-to-grasp tasks to receive recommendations for self-managed exercises or progress reports. Sensing equipment aside from cameras is typically unavailable in the home environment. A key contribution of our work is to propose a deep learning-based assessment model trained only with video data. As all patients carry out identical tasks, a fine-grained assessment of task execution is required. Our model addresses this difficulty by learning RGB and optical flow data in a complementary manner. The correlation between the RGB and optical flow data is captured by a novel module for modality fusion using cross-attention with Transformers. Experiments showed that our model achieved higher accuracy in movement assessment than existing methods for action recognition. Based on the assessment model, we developed a patient-centered, solution-based mobile application for upper extremity exercises for hemiplegia, which can recommend 57 exercises with three levels of difficulty. A prototype of our application was evaluated by potential end-users and achieved a good quality score on the Mobile Application Rating Scale (MARS).

Association between lipid levels and the risk of Parkinson's disease in individuals with diabetes mellitus: A nationwide population-based cohort study.

INTRODUCTION: Many studies have examined the positive association between diabetes mellitus (DM) and the risk of Parkinson's disease (PD). Dyslipidemia has been reported to be prevalent in patients with diabetes; thus, lipid levels and the drugs for dyslipidemia could influence the development of PD in patients with DM. This study aimed to examine the association between lipid levels and the risk of PD in individuals with DM and evaluate whether the association changes with the use of statins. METHODS: This nationwide population-based retrospective cohort study included individuals with DM according to the International Classification of Diseases between 2009 and 2012. Among the 2,361,633 patients with DM followed up for up to 9 years, 17,046 were newly diagnosed with PD. Patients with DM were categorized into quartile groups of total cholesterol, low-density lipoprotein cholesterol, and triglyceride levels. RESULTS: There was an inverse association between lipid levels and PD development in the unadjusted model; however, this relationship became less significant after adjusting the use of statins in triglyceride and total cholesterol. In the analysis stratified by statin use, total cholesterol level was associated with decreased PD risk in non-statin users with DM; however, there was no significant association between total cholesterol level and PD risk in statin users. CONCLUSION: We found an inverse relationship between lipid levels and PD risk in patients with DM, which was influenced by statin use. Future studies about optimal target lipid levels relevant to PD risk considering statin dose in DM patients are needed.

Application of deep learning technology for temporal analysis of videofluoroscopic swallowing studies.

Temporal parameters during swallowing are analyzed for objective and quantitative evaluation of videofluoroscopic swallowing studies (VFSS). Manual analysis by clinicians is time-consuming, complicated and prone to human error during interpretation; therefore, automated analysis using deep learning has been attempted. We aimed to develop a model for the automatic measurement of various temporal parameters of swallowing using deep learning. Overall, 547 VFSS video clips were included. Seven temporal parameters were manually measured by two physiatrists as ground-truth data: oral phase duration, pharyngeal delay time, pharyngeal response time, pharyngeal transit time, laryngeal vestibule closure reaction time, laryngeal vestibule closure duration, and upper esophageal sphincter opening duration. ResNet3D was selected as the base model for the deep learning of temporal parameters. The performances of ResNet3D variants were compared with those of the VGG and I3D models used previously. The average accuracy of the proposed ResNet3D variants was from 0.901 to 0.981. The F1 scores and average precision were 0.794 to 0.941 and 0.714 to 0.899, respectively. Compared to the VGG and I3D models, our model achieved the best results in terms of accuracy, F1 score, and average precision values. Through the clinical application of this automatic model, temporal analysis of VFSS will be easier and more accurate.

Association between Low Blood Pressure and Subsequent Risk of Parkinson's Disease in Older Adults Aged ≥75 Years.

INTRODUCTION: The association between blood pressure (BP) and incidence of Parkinson's disease (PD) in older adults remains uncertain. Therefore, this study aimed to investigate the association between BP (high or low) and PD incidence in adults aged ≥75 years. METHODS: In this nationwide population-based cohort study, we enrolled participants aged ≥75 years without a prior PD diagnosis who had undergone health examination provided by the Korean National Health Insurance Service at least once from January 1, 2009, to December 31, 2012. The participants were followed up until December 31, 2019, or the date of their death. The Cox proportional hazards model was used to assess the risk of PD depending on systolic BP (SBP), diastolic BP (DBP), and pulse pressure. RESULTS: Overall, 963,525 participants were enrolled in the analysis and followed up until December 31, 2019, or the date of death (40.7% male, mean age 78.5 ± 3.6 years). The mean SBP and DBP were 131.4 ± 16.7 and 77.9 ± 10.3 mm Hg, respectively. During the 10-year follow-up period, 16,414 (1.7%) newly diagnosed cases of PD were reported. A significant inverse dose-response association was found between SBP and PD incidence. In the subgroup analysis, this association was maintained for most variables, including sex, use of antihypertensive medication, comorbidities, alcohol consumption, physical activity, and body mass index, except for smoking status. CONCLUSION: Lower SBP and DBP were associated with a higher PD incidence in older adults. These results may have substantial implications for determining the optimal BP control target in adults aged ≥75 years.

Accessibility for Rehabilitation Therapy According to Socioeconomic Status in Patients With Stroke: A Population-Based Retrospective Cohort Study.

This study aimed to investigate accessibility for rehabilitation therapy according to socioeconomic status (SES) after stroke using nationwide population-based cohort data. We selected patients with a diagnosis with stroke (International Classification of Diseases, 10th Revision code: I60-64) and SES including residential area, income level, and insurance type were also assessed. Receiving continuous rehabilitation therapy was defined as accumulation of "Rehabilitative developmental therapy for disorder of central nervous system (claim code: MM105)" more than 41 times. Logistic regression analyses were performed to investigate the association between SES and rehabilitation therapy using odds ratios (ORs) and 95% confidence intervals (CIs). A total of 18,842 patients with stroke were enrolled. Rural area (OR, 0.745; 95% CI, 0.664-0.836) and medical aid (OR, 0.605; 95% CI, 0.494-0.741) were associated with lower rate of receiving rehabilitation therapy. As for income level, when lowest income group was used as a reference group, low-middle group showed an increased rate of receiving rehabilitation therapy (OR, 1.206; 95% CI, 1.020-1.426). Although rehabilitation therapy after stroke is covered with national health insurance program in Korea, there still existed disparities of accessibility for rehabilitation therapy according to SES. Our results would suggest helpful information for health policy in patients with stroke.

Comparing the Effectiveness of Physical Rehabilitation Interventions for Post-Stroke Function and Mobility Recovery: A Meta-Analysis.

Various interventions to physical rehabilitation have been used after stroke, including musculoskeletal, neurophysiological, and motor learning interventions, with ongoing debates and controversies about their relative effectiveness. In this systematic review, we searched 3 international electronic databases (MEDLINE, Embase, and Cochrane Library) to identify relevant studies. We included only randomized controlled trials (RCTs) that directly compared motor relearning, neurophysiological, and musculoskeletal interventions for improving motor function in adult stroke patients. Risk of bias (RoB) assessment was performed using Cochrane's RoB tool, and meta-analysis was conducted using Revman 5.4 with a random effects model. Certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development, and Evaluations method. The meta-analysis for immediate outcome for physical rehabilitation included 9 RCTs for balance, 10 RCTs for gait velocity, 7 RCTs for lower extremity motor function and 8 RCTs for performance of activities of daily living. There was no statistically significant different on improvement of balance, gait velocity, lower extremity motor function and performance of activity among physical rehabilitation interventions. Moderate-level evidence supports that no single intervention is superior. Clinicians and therapist should consider individual patient characteristics, preferences, and available resources when selecting the intervention for stroke rehabilitation.

Clinical Practice Guideline for Stroke Rehabilitation in Korea-Part 1: Rehabilitation for Motor Function (2022).

This clinical practice guideline (CPG) is the fourth edition of the Korean guideline for stroke rehabilitation, which was last updated in 2016. The development approach has been changed from a consensus-based approach to an evidence-based approach using the Grading of Recommendations Assessment Development and Evaluation (GRADE) method. This change ensures that the guidelines are based on the latest and strongest evidence available. The aim is to provide the most accurate and effective guidance to stroke rehabilitation teams, and to improve the outcomes for stroke patients in Korea. Fifty-five specialists in stroke rehabilitation and one CPG development methodology expert participated in this development. The scope of the previous clinical guidelines was very extensive, making it difficult to revise at once. Therefore, it was decided that the scope of this revised CPG would be limited to Part 1: Rehabilitation for Motor Function. The key questions were selected by considering the preferences of the target population and referring to foreign guidelines for stroke rehabilitation, and the recommendations were completed through systematic literature review and the GRADE method. The draft recommendations, which were agreed upon through an official consensus process, were refined after evaluation by a public hearing and external expert evaluation.

Efficiency of botulinum toxin injection into the arm on postural balance and gait after stroke.

The purpose of this study was to clarify the association between improvement of spasticity in hemiplegic patient's upper extremity with Botulinum toxin injection and improvement in postural balance and gait function. For this prospective cohort study, sixteen hemiplegic stroke patients with upper extremity spasticity were recruited. The plantar pressure with gait parameters, postural balance parameters, Modified Ashworth Scale, and Modified Tardieu Scale were evaluated before, 3 weeks and 3 months after Botulinum toxin A (BTxA) injection. Spasticity of hemiplegic upper extremity before, and after BTxA injection were significantly changed. Plantar pressure overload in affected side was reduced after BTxA injection. The mean X-speed and the horizontal distance decreased in postural balance analysis with eyes-opened test. Improvement in hemiplegic upper extremity spasticity showed positive correlation with gait parameters. In addition, improvement in hemiplegic upper extremity spasticity was positively correlated with change in balance parameters in postural balance analysis with eyes-closed and dynamic tests. This study focused on the effect of stroke patient's hemiplegic upper extremity spasticity on their gait and balance parameters and identified that the BTxA injection on hemiplegic patient's spastic upper extremity improve postural balance and gait function.

Association between smoking and all-cause mortality in Parkinson's disease.

We aimed to investigate the association between smoking status and all-cause mortality of Parkinson's disease (PD). Among the whole nationwide population data from Korea National Health Insurance Service, newly diagnosed PD was selected, and all-cause mortality was evaluated. The systematic review was performed through a literature search on the PubMed, EMBASE, and Cochrane Central Register of Controlled Trials databases. Among 26,080 individuals with PD, there was no significant association between smoking status and all-cause mortality in a nationwide cohort study (ex-smoker, HR 0.1.03, 95% CI 0.97-1.10; current smoker, HR 1.06, 95% CI 0.96-1.16). The systematic review, including six prospective cohort studies, also found a nonsignificant association. PD smokers tended to have fewer deaths from neurologic causes but were significantly more likely to die from smoking-related cancers such as lung cancer. We presented a nonsignificant association between smoking and mortality of PD, and cigarette smoking is not recommended in individuals with PD.

Quantitative Analysis of Temporal Parameters Correlated with Aspiration and Lesion Location in Stroke Patients.

The purpose of this study was to identify differences in temporal parameters correlating to the presence of aspiration and the severity of penetration-aspiration scale (PAS) in patients with dysphagia after stroke. We also investigated whether there was a significant difference in temporal parameters based on the location of the stroke lesion. A total of 91 patient videofluoroscopic swallowing study (VFSS) videos of stroke patients with dysphagia were retrospectively analyzed. Various temporal parameters including oral phase duration, pharyngeal delay time, pharyngeal response time, pharyngeal transit time, laryngeal vestibule closure reaction time, laryngeal vestibule closure duration, upper esophageal sphincter opening duration and upper esophageal sphincter reaction time were measured. Subjects were grouped by the presence of aspiration, PAS score, and location of the stroke lesion. Pharyngeal response time, laryngeal vestibule closure duration, and upper esophageal sphincter opening duration were significantly prolonged in the aspiration group. These three factors showed positive correlation with PAS. In terms of stroke lesion, oral phase duration was significantly prolonged in the supratentorial lesion group, while upper esophageal sphincter opening duration was significantly prolonged in the infratentorial lesion group. We have demonstrated that quantitative temporal analysis of VFSS can be a clinically valuable tool identifying dysphagia pattern associated with stroke lesion or aspiration risk.

The reliability and validity of the Korean version of the reaching performance scale for stroke after translation and cross-cultural adaptation.

The reaching performance scale for stroke evaluates reach-to grasp movement of the upper extremity and compensatory movements. The objective of the study was to translate and cross-culturally adapt the reaching performance scale for stroke into Korean and assess its reliability and validity. An expert committee supervised the forward and backward translation and the final translated Korean version of reaching performance scale for stroke (K-RPSS). Ninety-eight individuals (mean age 63.63 ± 13.13 years), with hemiplegia after stroke (97.82 ± 191.50 weeks) were evaluated independently by physiatrist and occupational therapist using K-RPSS. Degree of the motor impairment and functional status of patients were evaluated with the Fugl-Meyer assessment for upper limb and manual function test. The K-RPSS demonstrated excellent intra-rater (intraclass correlation coefficient = 0.9865), inter-rater (intraclass correlation coefficient 0.9866) reliability, and internal consistency (Cronbach α = 0.977 for total score). The validity of K-RPSS was confirmed with strong correlation with Fugl-Meyer assessment and manual function test. The K-RPSS had ceiling effect and the 3 points is the score change needed to indicate a change in a patient. K-RPSS has been shown to be a reliable and valid tool for assessing the compensation and movement quality of the upper limb and trunk when performing a reach-to grasp task. The K-RPSS is expected to be used widely by Korean speaking clinicians and researchers.

Machine learning based risk prediction for Parkinson's disease with nationwide health screening data.

Although many studies have been conducted on machine learning (ML) models for Parkinson's disease (PD) prediction using neuroimaging and movement analyses, studies with large population-based datasets are limited. We aimed to propose PD prediction models using ML algorithms based on the National Health Insurance Service-Health Screening datasets. We selected individuals who participated in national health-screening programs > 5 times between 2002 and 2015. PD was defined based on the ICD-code (G20), and a matched cohort of individuals without PD was selected using a 1:1 random sampling method. Various ML algorithms were applied for PD prediction, and the performance of the prediction models was compared. Neural networks, gradient boosting machines, and random forest algorithms exhibited the best average prediction accuracy (average area under the receiver operating characteristic curve (AUC): 0.779, 0.766, and 0.731, respectively) among the algorithms validated in this study. The overall model performance metrics were higher in men than in women (AUC: 0.742 and 0.729, respectively). The most important factor for predicting PD occurrence was body mass index, followed by total cholesterol, glucose, hemoglobin, and blood pressure levels. Smoking and alcohol consumption (in men) and socioeconomic status, physical activity, and diabetes mellitus (in women) were highly correlated with the occurrence of PD. The proposed health-screening dataset-based PD prediction model using ML algorithms is readily applicable, produces validated results, and could be a useful option for PD prediction models.

Initial BMI and Weight Loss over Time Predict Mortality in Parkinson Disease.

OBJECTIVES: Although weight loss is a frequent symptom in Parkinson disease (PD), there have been few studies on the association between body mass index (BMI) and mortality. The objective of this study was to investigate the association between BMI and change in BMI at diagnosis in patients with PD and all-cause mortality. DESIGN: Cohort study using Korean National Health Insurance Service-Elderly Cohort data. SETTING AND PARTICIPANTS: Patients with new-onset PD were selected using the International Classification of Diseases 10th edition code (G20). Then, patients who were diagnosed more than 3 times with PD and had been prescribed anti-parkinsonian medication for ≥30 days were included. Those with a combined diagnosis of atypical parkinsonism and secondary parkinsonism were excluded. METHODS: The primary outcome was all-cause mortality. Anthropometric data, including height and weight, were obtained from the health screening data to calculate BMI. The Cox proportional hazards model was used to assess mortality risk by BMI. RESULTS: Among the 2703 patients with PD, 492 (18.20%) died during the 11-year follow-up period. There was a significant inverse dose-response relationship between baseline BMI and mortality [<18.5 kg/m2: hazard ratio (HR), 1.872, 95% CI, 1.338-2.494; 23-25 kg/m2: HR, 0.695, 95% CI, 0.546-0.886; 25-30 kg/m2: HR, 0.644, 95% CI, 0.476-0.869; ≥30 kg/m2: HR, 0.396, 95% CI, 0.165-0.950]. Change in BMI of 10% revealed a significant association with mortality. Subgroup analyses by sex showed a significant inverse dose-response relationship between BMI and all-cause mortality only in women. CONCLUSIONS AND IMPLICATIONS: We demonstrated an inverse dose-response association between BMI at diagnosis and mortality in patients with PD, especially in women. Early detection of PD before weight loss progression and proper management might improve mortality. The small number of obese PD participants in our study should be considered when interpreting and generalizing results.

Ankylosing Spondylitis: A Risk Factor for Parkinsonism-A Nationwide Population-Based Study.

BACKGROUND: Ankylosing spondylitis (AS) is an immune-mediated, chronic inflammatory rheumatic disorder. The etiology of Parkinson's disease (PD) is multifactorial; however, inflammation is receiving an increasing amount of attention as an underlying cause of the neurodegenerative process of PD. OBJECTIVE: We performed a nationwide longitudinal, population-based matched cohort study to assess the association with the later development of parkinsonism in Korea. METHODS: This study was conducted using records from the Health Insurance Review and Assessment Service database. The cumulative incidence rate of PD was estimated. Fine-Gray subdistribution hazard models were used to identify hazards associated with PD development based on the presence of AS. Exposure to anti-inflammatory drugs was measured and analyzed to determine the protective effect of these medications. Additionally, the hazard ratio (HR) for atypical parkinsonism was estimated. RESULTS: The results of the Fine-Gray subdistribution hazard model revealed that the HR for PD development in the AS group was 1.82 (95%confidence interval [CI], 1.38-2.39, p < 0.001). A significant decrease in PD development was observed in patients with AS taking non-steroidal anti-inflammatory drugs (NSAIDs). The HR for atypical parkinsonism in the AS group was 3.86 (95%CI, 1.08-13.78, p < 0.05). CONCLUSION: We found that AS was associated with an increased risk of PD and atypical parkinsonism. NSAIDs used for AS control have some protective effects against PD. Further studies assessing whether biological treatment mitigates PD risk in patients with high activity are warranted.

Diagnosis of Post-Stroke Aphasia: A Review of Language Tests in Korea.

Aphasia is one of the most serious cognitive impairments in stroke patients. An accurate diagnosis of aphasia is important for early interventions that optimize patients' functional status. Therefore, we present a review of the aphasia assessment tools currently available in Korea. Aphasia is usually evaluated using a standardized comprehensive assessment battery to establish the diagnosis of aphasia, its severity, and the treatment plan. Before a comprehensive language test, a brief screening test for aphasia can be useful to identify whether any further assessment is necessary. Several standardized evaluation tools are readily available in Korea. The Paradise-Korean version of the Western Aphasia Battery (PK-WAB) is a commonly used comprehensive aphasia test for determining the presence, type, and severity of aphasia. The Korean version of the Boston Naming Test (K-BNT) is an in-depth test to evaluate naming ability. Several screening tests, such as the Korean version of the Frenchay Aphasia Screening Test (K-FAST), the Screening Test for Aphasia and Neurologic Communication Disorders (STAND), and Semantic Verbal Fluency (SVF), can be applied to identify patients at risk in terms of language performance. Depending on the outcome of these tests, patients can be referred for further evaluation.

Association of Physical Activity, Including Amount and Maintenance, With All-Cause Mortality in Parkinson Disease.

Importance: The protective effects of physical activity (PA) against Parkinson disease (PD) development have been suggested; however, the association of PA with mortality in PD has rarely been investigated. Objective: To evaluate the association between PA and mortality in individuals with PD and determine how the amount and maintenance of PA are associated with mortality. Design, Setting, and Participants: This nationwide population-based cohort study used Korean National Health Insurance System data. Participants were included from January 1, 2010, and December 31, 2013, and were followed up until December 31, 2017. Data were analyzed from September 2020 to March 2021. Individuals who were newly diagnosed with PD were selected using the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision code G20 and registration code V124 in the program for rare intractable diseases in 2010 through 2013. Individuals who underwent health checkups within 2 years before and after the PD diagnosis were enrolled. Those aged younger than 40 years or with missing data were excluded. Exposures: Physical activity levels were collected using self-reported questionnaires. Main Outcomes and Measures: All-cause mortality. Results: A total of 45 923 individuals were identified; 10 987 were enrolled, and 34 individuals younger than 40 years and 254 with missing data were excluded. A total of 10 699 individuals with PD were included; 4925 (46%) were male and 5774 (54%) were female, and the mean (SD) age was 69.2 (8.8) years. During the 8-year follow-up period, there were 1823 deaths (17%). The mortality rate was lower among individuals who were physically active vs inactive at all PA intensities (vigorous: hazard ratio [HR], 0.80 [95% CI, 0.69-0.93]; moderate: HR, 0.66 [95% CI, 0.55-0.78]; light: HR, 0.81 [95% CI, 0.73-0.90]). There was a significant inverse dose-response association between the total amount of PA and mortality (HRs: vigorous, 0.80 [95% CI, 0.69-0.93]; moderate, 0.66 [95% CI, 0.55-0.78]; light, 0.81 [95% CI, 0.73-0.90]; P < .001). Moreover, maintenance of PA was associated with the mortality rate. Individuals with PD who were physically active both before and after the PD diagnosis had the greatest reduction in mortality rate across all PA intensities (HRs: vigorous, 0.66 [95% CI, 0.50-0.88]; moderate, 0.49 [95% CI, 0.32-0.75]; light, 0.76 [95% CI, 0.66-0.89]). Individuals who started PA after receiving the PD diagnosis had a lower mortality rate than those who remained physically inactive (HRs: vigorous, 0.82 [95% CI, 0.70-0.97]; moderate, 0.69 [95% CI, 0.57-0.83]; light, 0.86 [95% CI, 0.78-0.98]). Conclusions and Relevance: This analysis found a dose-response association between PA and all-cause mortality in PD. Reverse causality may exist, and future prospective randomized clinical trials are warranted to determine the effect of PA on mortality in PD.

Effects of diabetes mellitus on the rate of carpal tunnel release in patients with carpal tunnel syndrome.

The objective of this study was to evaluate the effects of diabetes mellitus (DM) on the rate of carpal tunnel release (CTR) using a large nationwide cohort in Korea and to identify risk factors, including comorbidities and socioeconomic status (SES), associated with CTR. Patients with a primary or secondary diagnosis of carpal tunnel syndrome (CTS; ICD-10 code: G560) were selected and divided into two groups according to the presence of DM. A Cox proportional hazard model was used to assess the rate of CTR between the two groups. To evaluate the influence of demographic factors, comorbidities, and SES on CTR, multivariate Cox proportional hazard regression models were used to adjust for confounding variables. In total, 12,419 patients with CTS were included in the study: 2487 in DM cohort and 9932 in non-DM cohort. DM duration was negatively related with the rate of CTR (HR = 0.89, 95% CI 0.87-0.91) in CTS patients with DM. The rate of CTR was decreased in patients with DM compared to those without DM in the unadjusted model; however, after adjusting for comorbidities, DM had no significant effect on the rate of CTR. Female sex (HR = 1.50, 95% CI 1.36-1.67) correlated with the rate of CTR, and an inverse relationship between the number of comorbidities and CTR was found (p < 0.001) irrespective of DM. Diabetic polyneuropathy (DPN) was not associated with CTR, and we did not find any factors correlating with CTR in DPN patients. We found that CTS patients with more comorbidities or combined with a longer duration of DM were undertreated in real-word practice. Actual outcomes of CTR in CTS patents with various comorbidities should be investigated in future studies for optimal management of CTS.