Objective: There is clinical concern that the stimulant methylphenidate (MPH) might increase the risk of depression, particularly in children. This study aimed to investigate the association between MPH use and the risk of depression. Methods: A population-based electronic medical records database was used. We obtained claims data for prescription of ADHD medication, diagnosis of depression, and prescription of antidepressant medication between January 2007 and December 2016 for 43,259 individuals aged 6 to 19 who were diagnosed with ADHD between July 1, 2007 and December 31, 2007. The final analysis was based on 2,330 eligible participants. A self-controlled case series design was used to identify risk factors for major depressive disorder (MDD). Results: An elevated MDD risk was found during the 90 days before MPH exposure, with an incidence rate ratio (IRR) of 12.12 (95% confidence interval [95% CI]: 10.06−14.61, p ＜ 0.0001). During methylphenidate treatment, the IRR was 18.06 with a 95% CI of 16.67 to 19.56 (p ＜ 0.0001), but it returned to baseline levels after day 31 of MPH treatment discontinuation. The IRR for patients aged 6 to 9 years was 13.11 (95% CI: 9.58−17.95) during the 90 days before MPH exposure, and 17.7 (95% CI: 15.6−20.08) during MPH treatment, but returned to baseline levels after discontinuation of MPH treatment. Conclusion We confirmed the temporal relationship between depression and methylphenidate use in young people with ADHD. Though the absolute risk is low, the risk of depression should be carefully considered, particularly in the period directly following the start of methylphenidate treatment.

Background/Aims: Clarithromycin resistance is a main factor for treatment failure in the contextof Helicobacter pylori infection. However, the treatment regimen for clarithromycin-resistant H. pylori infection has not yet been determined. We aimed to compare the efficacy and cost-effectiveness of 14-day bismuth-based quadruple therapy versus 14-day metronidazole-intensified triple therapy for clarithromycin-resistant H. pylori infection with genotypic resistance. Methods: This was a multicenter, randomized, controlled trial. A total of 782 patients with H. pylori infection examined using sequencing-based clarithromycin resistance point mutation tests were recruited between December 2018 and October 2020 in four institutions in Korea. Patients with significant point mutations (A2142G, A2142C, A2143G, A2143C, and A2144G) were randomly assigned to receive either 14-day bismuth-based quadruple therapy (n=102) or 14-day metronidazole-intensified triple therapy (n=99). Results: The overall genotypic clarithromycin resistance rate was 25.7% according to the sequencing method. The eradication rate of 14-day bismuth-based quadruple therapy was not significantly different in the intention-to-treat analysis (80.4% vs 69.7%, p=0.079), but was significantly higher than that of 14-day metronidazole-intensified triple therapy in the per-protocol analysis (95.1% vs 76.4%, p=0.001). There were no significant differences in the incidence of side effects. In addition, the 14-day bismuth-based quadruple therapy was more cost-effective than the 14-day metronidazole-intensified triple therapy. Conclusions Fourteen-day bismuth-based quadruple therapy showed comparable efficacy with 14-day metronidazole-intensified triple therapy, and it was more cost-effective in the context of clarithromycin-resistant H. pylori infection.

Objectives: Agent Orange is a defoliant chemical that is widely known for its use by the U.S. military during the Vietnam War. It is known to be associated with the occurrence of various diseases in exposed subjects. However, few previous studies have focused on the effects of exposure to Agent Orange on cognitive dysfunction. Methods: A total of 387 male subjects participated in the study. They were divided into those who were exposed to Agent Orange (n=301) and those without exposure (n=86). Both were evaluated with neuropsychological batteries, including the Consortium to Establish a Registry for Alzheimer’s Disease and the Seoul Neuropsychological Screening Battery-Second Edition. Results: The group exposed to Agent Orange showed significantly higher scores in the Rey Complex Figure Test copy and recognition compared to those without exposure. Conclusion In this study, we compared the effects of exposure to Agent Orange on cognitive function in groups that had not yet progressed to dementia. The Agent Orange exposure group showed better results in some tests evaluating visuospatial and memory function.

OBJECTIVES: This study estimated the overall incidence of iatrogenic Creutzfeldt-Jakob disease (iCJD) based on dura graft cases in Korea using a mathematical model. METHODS: We estimated the number of annual dura grafts performed between 1980 and 1995 by applying the proportion of dura grafts recorded by the Health Insurance Review Agency claim dataset in Korea to the number of nationwide neurosurgery cases. The distribution of the incubation period was assumed to fall under a Weibull distribution with density function or a log-logistic distribution with density function. RESULTS: The total number of neurosurgery procedures performed from 1980 to 1995 was estimated to be 263,945, and among those operations, 37% used dura graft products. Between the years of 1980 and 2020, our model predicted that the total number of iCJD cases would be between 14.9 and 33.2 (95% confidence interval [CI], 13.4 to 50.9). Notably, we estimated that the cumulative number of iCJD cases caused by dura grafts between 1980 and 2011 was approximately 13.3 to 27.3 (95% CI, 12.2 to 40.6). CONCLUSIONS: Based on our model, we postulate that the incidence of iCJD will sharply decline from 2012 to 2020. However, additional new cases are still expected, which necessitates a strong national surveillance system.
Cadaver* ; Creutzfeldt-Jakob Syndrome* ; Dataset ; Dura Mater* ; Incidence ; Insurance, Health ; Korea* ; Models, Theoretical ; Neurosurgery ; Prion Diseases ; Transplants*

OBJECTIVES: This study aimed to evaluate whether the birth rate is associated with socioeconomic status in the women of the Republic of Korea, where the birth rate is rapidly decreasing. METHODS: This study included 732 females from the Healthy Twin Study, a family-twin cohort. The participants were classified into 3 socioeconomic groups according to their average income, education, and occupation. The association between socioeconomic status and number of children was assessed using gamma regression analysis with a generalized linear mixed model, adjusting for the age group, smoking/alcohol status, and family relationships. RESULTS: The group with the highest education level had significantly fewer children compared with the group with the lowest education level (p=0.004). However, no significant associations were found according to household income level. The non-manual labor group had significantly fewer children compared with those working as homemakers (p=0.008). CONCLUSIONS: This study aimed to explain the causal relationship between socioeconomic status and number of children. Associations between some socioeconomic status and number of children were found in Korea.
Adult ; Aged ; Alcohol Drinking ; Asian Continental Ancestry Group ; *Birth Rate ; Child ; Cohort Studies ; Family Relations ; Female ; Humans ; Income ; Middle Aged ; Occupations ; Regression Analysis ; Republic of Korea ; Smoking ; Socioeconomic Factors ; Twins ; Women/*psychology

OBJECTIVES: We examined the association between social expenditures of the local government and the mortality level in Korea, 2004 to 2010. METHODS: We used social expenditure data of 230 local governments during 2004 to 2010 from the Social Expenditure Database prepared by the Korean Institute for Health and Social Affairs. Fixed effect panel data regression analysis was adopted to look for associations between social expenditures and age-standardized mortality and the premature death index. RESULTS: Social expenditures of local governments per capita was not significantly associated with standardized mortality but was associated with the premature death index (decline of 1.0 [for males] and 0.5 [for females] for each expenditure of 100 000 Korean won, i.e., approximately 100 US dollar). As an index of the voluntary effort of local governments, the self-managed project ratio was associated with a decline in the standardized mortality in females (decline of 0.4 for each increase of 1%). The share of health care was not significant. CONCLUSIONS: There were associations between social expenditures of the local government and the mortality level in Korea. In particular, social expenditures per capita were significantly associated with a decline in premature death. However, the voluntary efforts of local governments were not significantly related to the decline in premature death.
Databases, Factual ; Female ; Financing, Government/*economics ; Health Expenditures/*statistics & numerical data ; Humans ; Local Government ; Male ; Mortality/*trends ; Mortality, Premature/*trends ; Regression Analysis ; Republic of Korea