Background: The clinical implications of myelin oligodendrocyte glycoprotein autoantibodies (MOG-Abs) are increasing. Establishing MOG-Ab assays is essential for effectively treating patients with MOG-Abs. We established an in-house cell-based assay (CBA) to detect MOG-Abs to identify correlations with patients’ clinical characteristics. Methods: We established the CBA using HEK 293 cells transiently overexpressing fulllength human MOG, tested it against 166 samples from a multicenter registry of central nervous system (CNS) inflammatory disorders, and compared the results with those of the Oxford MOG-Ab-based CBA and a commercial MOG-Ab CBA kit. We recruited additional patients with MOG-Abs and compared the clinical characteristics of MOG-Ab-associated disease (MOGAD) with those of neuromyelitis optica spectrum disorder (NMOSD). Results: Of 166 samples tested, 10 tested positive for MOG-Abs, with optic neuritis (ON) being the most common manifestation (4/15, 26.7%). The in-house and Oxford MOG-Ab CBAs agreed for 164/166 (98.8%) samples (κ = 0.883, P < 0.001); two patients (2/166, 1.2%) were only positive in our in-house CBA, and the CBA scores of the two laboratories correlated well (r = 0.663, P < 0.001). The commercial MOG-Ab CBA kit showed one falsenegative and three false-positive results. The clinical presentation at disease onset differed between MOGAD and NMOSD; ON was the most frequent manifestation in MOGAD, and transverse myelitis was most frequent in NMOSD. Conclusions The in-house CBA for MOG-Abs demonstrated reliable results and can potentially be used to evaluate CNS inflammatory disorders. A comprehensive, long-term study with a large patient population would clarify the clinical significance of MOG-Abs.

Background and Objectives: Wireless streaming technology (WT), designed to transmit sounds directly from a mobile phone to hearing aids, was developed to enhance the signal-to-noise ratio. However, the advantages of WT during phone use and the specific demographic that can fully benefit from this technology has not been thoroughly evaluated. We aimed to investigate the benefits and identify predictive factors associated with bilateral wireless streaming among hearing aid users. Subjects and Methods: Eighteen adults with symmetrical, bilateral hearing loss participated in the study. To assess the benefits of wireless streaming during phone use, researchers assessed sentence/word recognition and listening effort in two scenarios: a noisy background with WT turned “OFF” or “ON.” Listening effort was evaluated through self-reported measurements. Cognitive function was also assessed using the Montreal Cognitive Assessment (MoCA) score. Results: Participant mean age was 57.3 years (range 27-70), and the mean MoCA score was 27.0 (23-30). The activation of WT demonstrated a significant improvement in the sentence/word recognition test and reduced listening effort. The MoCA score showed a significant correlation with WT (ρ=0.59, p=0.01), suggesting a positive association between cognitive function and the benefits of WT. Conclusions Bilateral wireless streaming may enhance sentence/word recognition and reduce listening effort during phone use in hearing aid users, with these benefits potentially linked to cognitive function.

Purpose: Few studies have investigated the association between smoking and microvascular complications in the Asian population with type 2 diabetes mellitus (T2DM). We aimed to investigate the relationship between smoking status and microvascular complications in Korean patients with T2DM. Materials and Methods: From the Korean National Diabetes Program cohort, we included 2316 Korean male with T2DM who had baseline clinical information available, including their smoking status, and underwent diabetic complication studies. Results: Compared to non-smokers, current smokers had higher odds of any-microvascular complications [adjusted odds ratio (aOR) 1.45, 95% confidence interval (CI) 1.07–1.97, p=0.016]. The odds of neuropathy were significantly higher; however, the odds of retinopathy were significantly lower in current smokers than in nonsmokers (all p<0.05). Among those who underwent repeated complication tests after 3 years, the risk of newly developed retinopathy was significantly increased in ex-smokers [aOR 3.77 (95% CI 1.61–8.87), p=0.002]. Within ex-smokers, long smoking duration and smoking cessation within the recent 5 years were associated with an increased risk of newly developed retinopathy (all p<0.05). Conclusion Male smokers had higher odds of having overall diabetic microvascular complications, including neuropathy. However, the odds of having retinopathy were significantly lower among current smokers. More attention and research are needed regarding the increased risk of retinopathy development in ex-smokers who have recently stopped smoking after a long history of smoking.

Background: Recent reports have suggested that pneumonitis is a rare complication following vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).However, its clinical features and outcomes are not well known. The aim of this study was to identify the clinical characteristics and outcomes of patients with vaccine-associated pneumonitis following vaccination against SARS-CoV-2. Methods: In this nationwide multicenter survey study, questionnaires were distributed to pulmonary physicians in referral hospitals. They were asked to report cases of development or exacerbation of interstitial lung disease (ILD) associated with the coronavirus disease 2019 vaccine. Vaccine-associated pneumonitis was defined as new pulmonary infiltrates documented on chest computed tomography within 4 weeks of vaccination and exclusion of other possible etiologies. Results: From the survey, 49 cases of vaccine-associated pneumonitis were identified between February 27 and October 30, 2021. After multidisciplinary discussion, 46 cases were analyzed. The median age was 66 years and 28 (61%) were male. The median interval between vaccination and respiratory symptoms was 5 days. There were 20 (43%), 17 (37%), and nine (19%) patients with newly identified pneumonitis, exacerbation of pre-diagnosed ILD, and undetermined pre-existing ILD, respectively. The administered vaccines were BNT162b2 and ChAdOx1 nCov-19/AZD1222 each in 21 patients followed by mRNA-1273 in three, and Ad26.COV2.S in one patient. Except for five patients with mild disease, 41 (89%) patients were treated with corticosteroid. Significant improvement was observed in 26 (57%) patients including four patients who did not receive treatment. However, ILD aggravated in 9 (20%) patients despite treatment. Mortality was observed in eight (17%) patients. Conclusion These results suggest pneumonitis as a potentially significant safety concern for vaccines against SARS-CoV-2. Clinical awareness and patient education are necessary for early recognition and prompt management. Additional research is warranted to identify the epidemiology and characterize the pathophysiology of vaccine-associated pneumonitis.

Background: We assessed the myocardial infarction (MI), stroke, and all-cause death risks during follow-up according to the low-density lipoprotein cholesterol (LDL-C) levels among older adults. Methods: The Korean National Health Insurance Service datasets (2002 to 2020) were used for this population-based cohort study. The hazards of MI, stroke, and all-cause mortality during follow-up were analyzed according to LDL-C level in individuals aged ≥65 years without baseline cardiovascular diseases (n=1,391,616). Results: During a mean 7.55 years, 52,753 MIs developed; 84,224 strokes occurred over a mean 7.47 years. After a mean 8.50 years, 233,963 died. A decrease in LDL-C was associated with lower hazards of MI and stroke. The decreased hazard of stroke in lower LDL-C was more pronounced in statin users, and individuals with diabetes or obesity. The hazard of all-cause death during follow-up showed an inverted J-shaped pattern according to the LDL-C levels. However, the paradoxically increased hazard of mortality during follow-up in lower LDL-C was attenuated in statin users and individuals with diabetes, hypertension, or obesity. In statin users, lower LDL-C was associated with a decreased hazard of mortality during follow-up. Conclusion Among the elderly, lower LDL-C was associated with decreased risks of MI and stroke. Lower LDL-C achieved by statins in the elderly was associated with a decreased risk of all-cause death during follow-up, suggesting that LDL-C paradox for the premature death risk in the elderly should not be applied to statin users. Intensive statin therapy should not be hesitated for older adults with cardiovascular risk factors including diabetes.

Purpose: The characteristic topography and climate often affect the occurrence of large-scale wildfires in the Eastern Gangwon-do region of Korea. However, there are no studies on the health effects of these wildfires in Korea. This study aimed to analyze the differences in medical use between a wildfire-affected area and an adjacent non-affected area before and after a wildfire in 2019 in Gangwon-do, Korea. Materials and Methods: We used medical usage data from the Korean National Health Insurance Corporation. Rates of medical use were determined for citizens of a wildfire-affected area in the Eastern Yeongdong region and a non-affected area in the Western Yeongseo region. Logistic regression analysis was performed considering an increase in medical use per individual as a dependent variable; age, sex, income, smoking, drinking, and exercise were included as confounding variables. Results: The odds ratio for medical use in Yeongdong region increased significantly after 3 days, 3 months, and 1 year after a fire occurred, compared with Yeongseo region. Conclusion The results of this study confirmed that the use of medical care increased for residents of a wildfire-affected area, compared with those of an adjacent non-affected area. This is the first study on the relationship between wildfires and inpatient medical use in Korea.

The age- and sex-related differences on the impacts of body composition on diabetes mellitus (DM) remain uncertain.

The age- and sex-related differences on the impacts of body composition on diabetes mellitus (DM) remain uncertain.

Objective: We investigated the effects of statin-ezetimibe combination therapy compared with statin-only treatment on the hazard of incident type 2 diabetes (T2D), myocardial infarction (MI), and stroke among adults with impaired fasting glucose (IFG) in a real-world setting. Methods: The Korean National Health Insurance Service datasets from 2002 to 2017 were used for this propensity-matched nationwide cohort study. Among 56,633 IFG patients without baseline cardiovascular disease (CVD) and/or T2D who initiated statin therapy with or without ezetimibe, 1,155 with statin-ezetimibe combination therapy were matched based on a propensity score at a 1:5 ratio with 5,775 patients who received statin monotherapy. The hazards of T2D, MI, and stroke were compared between these treatment groups. Results: The incidence rate per 1,000 person-years was 19.62 (statin monotherapy group) and 21.02 (combined treatment group) for T2D, 1.53 (statin monotherapy group) and 1.70 (combined treatment group) for MI, and 1.99 (statin monotherapy group) and 2.06 (combined treatment group) for stroke. The hazards of T2D, MI, and stroke were not significantly different between the statin monotherapy group and the statin-ezetimibe combination therapy group. Conclusion The combination of ezetimibe in addition to statin treatment was not associated with a significantly different risk of T2D and CVDs compared with statin monotherapy in Korean adults with IFG.

Background: The age- and sex-related differences on the impacts of body composition on diabetes mellitus (DM) remain uncertain. Methods: The fourth and fifth Korea National Health and Nutrition Examination Survey included 15,586 subjects over 30 years of age who completed dual-energy X-ray absorptiometry. We conducted a cross-sectional study to investigate whether muscle mass index (MMI), defined as appendicular skeletal muscle divided by body mass index (BMI), and fat mass index (FMI), defined as trunk fat mass divided by BMI, were differently associated with DM according to age and sex. Results: In multivariate logistic regression, the risk for DM significantly increased across quartiles of FMI in men aged ≥70.Meanwhile, MMI showed a protective association with DM in men of the same age. The odds ratios (ORs) for the highest quartile versus the lowest quartile of FMI and MMI were 3.116 (95% confidence interval [CI], 1.405 to 6.914) and 0.295 (95% CI, 0.157 to 0.554), respectively. In women, the ORs of DM was significantly different across FMI quartiles in those over age 50. The highest quartile of FMI exhibited increased ORs of DM in subjects aged 50 to 69 (OR, 1.891; 95% CI, 1.229 to 2.908) and ≥70 (OR, 2.275;95% CI, 1.103 to 4.69) compared to lowest quartile. However, MMI was not significantly associated with DM in women of all age groups. Conclusion Both FMI and MMI were independent risk factors for DM in men aged 70 years or more. In women over 50 years, FMI was independently associated with DM. There was no significant association between MMI and DM in women.