Epidemiology of Chronic Inflammatory Demyelinating Polyneuropathy in South Korea: A Population-Based Study.

BACKGROUND AND PURPOSE: We performed a population-based study to determine the prevalence and incidence of chronic inflammatory demyelinating polyneuropathy (CIDP) in South Korea using data from the Korean Health Insurance Review and Assessment Service (HIRA) database. METHODS: Data recorded in the HIRA database between January 2016 and December 2020 were analyzed. The inclusion criteria in this study for patients with CIDP were a diagnostic code of G61.8 in the seventh and eighth revision of the Korean Standard Classification of Disease and a >3-month history of oral immunosuppressant use. The age-adjusted incidence rate and prevalence of CIDP in South Korea were also analyzed. RESULTS: CIDP was newly diagnosed in 953 patients during the study period. The mean age at diagnosis was 58.36 years, and the male-to-female ratio was 1.74. The age-adjusted incidence rates were 0.22, 0.21, 0.23, 0.30, and 0.25 per 100,000 person-years in 2016, 2017, 2018, 2019, and 2020, respectively. The age-adjusted prevalence was estimated at 1.16 per 100,000 persons in 2020. Age and the Elixhauser Comorbidity Index were associated with the in-hospital mortality of patients with CIDP. Infection and cardiovascular disease (CVD) were also significantly associated with the in-hospital mortality of those patients. Acute-onset CIDP was initially diagnosed in an estimated 101 out of 953 patients with CIDP. CONCLUSIONS: The prevalence and incidence rates of CIDP in South Korea were comparable between this nationwide cohort study and previous studies. Common comorbidities such as CVD and diabetes should be appropriately monitored in patients with CIDP to prevent a poor prognosis and socioeconomic burden.

Fatty Liver Index for Predicting Nonalcoholic Fatty Liver Disease in an Asymptomatic Korean Population.

Nonalcoholic fatty liver disease (NAFLD) is increasing worldwide, highlighting the importance of early and accurate detection and the appropriate management of NAFLD. However, ultrasonography (US) is not included in many mass screening programs, and people have limited access to it. The aim of this study is to validate the fatty liver index (FLI) and investigate the optimal cutoff value for predicting NAFLD in an asymptomatic population. We conducted a retrospective cohort study in Korea. All subjects who underwent health checkup exams, including abdominal US, controlled attenuation parameter (CAP) and blood testing, were enrolled. Analyses of the area under the receiver operating characteristic curve (AUROC) were used to evaluate the diagnostic accuracy and to calculate the optimal FLI cutoff for US-NAFLD. Among the 4009 subjects (mean age 54.9 years, 83.5% male), the prevalence of US-diagnosed NAFLD and CAP-defined hepatic steatosis was 61.4% and 55.4%. The previously used cutoff of FLI = 60 showed poor performance in predicting US-diagnosed NAFLD, with an AUROC of 0.63 (0.62-0.64), and CAP-defined NAFLD, with an AUROC 0.63 (0.62-0.64). The optimal FLI cutoff values to discriminate fatty liver detected by US were 29 for the entire population, with an AUROC of 0.82 (0.81-0.84). The sex-specific values were 31 for males and 18 for females (sensitivity 72.8% and 73.4%; specificity 74.2% and 85.0%, respectively). The FLI cutoff for US-diagnosed NAFLD can be set as 29 for the entire Korean population. Considering the sex dimorphism in NAFLD, different cutoff values are suggested to predict US-diagnosed NAFLD. These results may be helpful in the accurate non-invasive diagnosis of NAFLD.

Association of Chocolate Consumption with Hearing Loss and Tinnitus in Middle-Aged People Based on the Korean National Health and Nutrition Examination Survey 2012⁻2013.

Chocolate, which is produced from cocoa, exerts antioxidant and anti-inflammatory effects that ameliorate neurodegenerative diseases. We hypothesized that chocolate consumption would protect against hearing loss and tinnitus. We evaluated the hearing and tinnitus data, as well as the chocolate consumption, of middle-aged participants (40⁻64 years of age) of the 2012⁻2013 Korean National Health and Nutrition Examination Survey. All of the subjects underwent a medical interview, physical examination, audiological evaluation, tinnitus questionnaire, and nutrition examination. A total of 3575 subjects 40⁻64 years of age were enrolled. The rate of any hearing loss (unilateral or bilateral) in the subjects who consumed chocolate (26.78% (338/1262)) was significantly lower than that in those who did not (35.97% (832/2313)) (p < 0.001). Chocolate consumption was independently associated with low odds of any hearing loss (adjusted odds ratio = 0.83, 95% confidence interval = 0.70 to 0.98, p = 0.03). Moreover, the severity of hearing loss was inversely correlated with the frequency of chocolate consumption. In contrast to chocolate, there was no association between hearing loss and the consumption of sweet products without cocoa. Chocolate consumption was also not associated with tinnitus or tinnitus-related annoyance. Our results suggest that a chocolate-based diet may protect middle-aged people from hearing loss.

Association of Coffee Consumption with Hearing and Tinnitus Based on a National Population-Based Survey.

Coffee is the one of the most common beverages worldwide and has received considerable attention for its beneficial health effects. However, the association of coffee with hearing and tinnitus has not been well studied. The aim of this study was to investigate the association of coffee with hearing and tinnitus based on a national population-based survey. We evaluated hearing and tinnitus data from the 2009⁻2012 Korean National Health and Nutrition Examination Survey and their relationship with a coffee consumption survey. All patients underwent a medical interview, physical examination, hearing test, tinnitus questionnaire and nutrition examination. Multivariable logistic regression models were used to examine the associations between coffee and hearing loss or tinnitus. We evaluated 13,448 participants (≥19 years) participants. The frequency of coffee consumption had a statistically significant inverse correlation with bilateral hearing loss in the 40⁻64 years age group. Daily coffee consumers had 50⁻70% less hearing loss than rare coffee consumers, which tended to be a dose-dependent relationship. In addition, the frequency of coffee consumption had an inverse correlation with tinnitus in the 19⁻64 years age group but its association was related with hearing. Brewed coffee had more of an association than instant or canned coffee in the 40⁻64 years age group. These results suggest a protective effect of coffee on hearing loss and tinnitus.