Background: As the coronavirus disease 2019 (COVID-19) has continued for a couple of years, the long-term effects of the pandemic and the subsequent school curriculum modification on the mental health of children and parents need to be investigated. To clarify the changes that can occur during one school year and to predict the risk factors for vulnerable groups, this study identified parameters relative to children’s screen time, their problematic behavior, and parental depression. Methods: A total of 186 participants were analyzed who were parents of elementary schoolchildren in South Korea. These parents were required to complete a web-based questionnaire twice. The questionnaires were conducted in June 2020 and September 2021. Participants’ general demographics including family income, children’s screen time, sleep patterns, problematic behavior, and parental depression were assessed via the parental questionnaire that included various measurement tools. Results: Children’s body mass index (BMI) increased significantly in 2021 (18.94 ± 3.75 vs. 18.14 ± 3.30, P < 0.001). Smartphone frequency of use per week (5.35 vs. 4.54, P < 0.001) and screen time per day (3.52 vs. 3.16, P < 0.001) significantly increased during the period of the COVID-19 pandemic. The television screen time (2.88 vs. 3.26, P < 0.001), frequency of viewing (3.77 vs. 4.77, P < 0.001), and children’s problematic behaviors significantly decreased (9.15 vs. 11.85,P < 0.001). A lower income household was a key predictor of increased smartphone frequency (B = 1.840, 95% confidence interval [CI], 0.923–2.757, P < 0.001) and smartphone screen time (B = 1.992, 95% CI, 1.458–2.525, P < 0.001). The results showed that the lower income household (B = 5.624, 95% CI, 2.927–8.320, P < 0.001) and a child’s psychiatric treatment history (B = 7.579, 95% CI, 5.666–9.492, P < 0.001) was the most significant predictor of problematic behaviors of children and parental depression (B = 3.476, 95% CI, 1.628–5.325, P < 0.001; B = 3.138, 95% CI, 1.827–4.450, P < 0.001). Conclusion This study suggested that children’s smartphone screen time and BMI increased during COVID-19 because of the school curriculum modification following school closures in South Korea. The increased children’s problematic behaviors and parental depression were predicted by lower-income households and the previous psychiatric history of children. These results indicate that multiple social support systems to the vulnerable group are needed during the ongoing pandemic and that a modified school setting is required.

BACKGROUND AND PURPOSE: The purpose of this study was to characterize abnormal cortical activity during sleep in restless legs syndrome (RLS) patients and to determine the effects of treatment with a dopamine agonist. Based on whole-brain electroencephalograms, we attempted to verify alterations in the functional network as well as the spectral power of neural activities during sleep in RLS patients and to determine whether the changes are reversed by treatment with pramipexole. METHODS: Twelve drug-naïve RLS patients participated in the study. Overnight polysomnography was performed before and after treatment: the first recording was made immediately prior to administering the first dose of pramipexole, and the second recording was made 12–16 weeks after commencing pramipexole administration. Sixteen age-matched healthy participants served as a control group. The spectral power and interregional phase synchrony were analyzed in 30-s epochs. The functional characteristics of the cortical network were quantified using graph-theory measures. RESULTS: The delta-band power was significantly increased and the small-world network characteristics in the delta band were disrupted in RLS patients compared to the healthy controls. These abnormalities were successfully treated by dopaminergic medication. The delta-band power was significantly correlated with the RLS severity score in the RLS patients prior to treatment. CONCLUSIONS: Our findings suggest that the spectral and functional network characteristics of neural activities during sleep become abnormal in RLS patients, and these abnormalities can be successfully treated by a dopamine agonist.
Delta Rhythm* ; Dopamine Agonists* ; Dopamine* ; Electroencephalography ; Healthy Volunteers ; Humans ; Polysomnography ; Restless Legs Syndrome*

Background/Aims: The association between symptomatic knee osteoarthritis (OA) and higher cardiovascular disease (CVD) mortality is established; however, findings from studies that utilized regression analysis were limited, attributed to the strong association between OA and metabolic risk factors. This study aimed to evaluate the association between knee OA and mortality through propensity score matching. Methods: This was a cohort study including Korean National Health and Nutrition Examination Survey (2010–2013) participants aged ≥ 50 years. By linking the survey data to cause of death data (through 2019) from Statistics Korea, mortality and cause-specific mortality data were obtained. Radiographic knee OA (ROA) was defined as bilateral Kellgren–Lawrence grade ≥ 2. Propensity score matching (1:1) was conducted between asymptomatic ROA, knee pain, and symptomatic ROA groups and normal groups, balancing the confounding factors. Time to death was analyzed using Cox proportional hazard modeling. Results: A higher CVD mortality was observed in the symptomatic ROA group, but not in others; the risk estimates were asymptomatic ROA (hazard ratio [HR] 1.12; 95% confidence interval [CI] 0.77–1.65), knee pain (HR 0.61; 95% CI 0.27–1.38), and symptomatic ROA (HR 1.39; 95% CI 0.89–2.17). No association was found between the all-cause/cancer mortality and other groups. Conclusions When propensity score matching controls metabolic risk factor imbalances, the association between symptomatic knee OA and higher CVD mortality was weaker compared to results of prior studies that used regression adjustment. The results may be more precise estimates of the total risk of knee OA for mortality in Koreans.

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.
Cataract Extraction ; Cornea ; Corneal Diseases ; Corneal Transplantation* ; Epidemiologic Studies* ; Eye Banks ; Humans ; Keratitis ; Keratoplasty, Penetrating ; Korea* ; Surveys and Questionnaires ; Tissue Donors ; Transplants

PURPOSE: To report an epidemiologic study of keratoplasty in which we analyze basic data of corneal transplants and corneal donations in Korea. METHODS: From June 2004 through October 2004, questionnaires were distributed to 25 hospitals. The questionnaires were about the characteristics of patients registered in eye banks for keratoplasty from May 2001 to April 2003, and about the results of keratoplasties performed from May 2002 to April 2003. RESULTS: The leading corneal diseases in patients registered for keratoplasty were infectious keratitis (22.0%), trauma (21.0%), and pseudophakic and aphakic bullous keratopathy (13.8%), in that order. The leading indications in corneal recipients were: trauma (15.5%), pseudophakic and aphakic bullous keratopathy (13.7%), and infectious keratitis (10.7%), in that order. In 233 cases of keratoplasties, penetrating keratoplasty was performed in 229 cases (98.3%) and lamellar keratoplasty was performed in 4 cases (1.7%). The most common combined surgery was cataract extraction. Common causes of graft failure were rejection of donor cornea and infection. Imported donor corneas were used in sixty-one cases (26.2%) among the 233 total keratoplasties. CONCLUSIONS: We constructed an epidemiologic data base of patients registered for keratoplasty, corneal donation, and the results of keratoplasties throughout Korea.
Cataract Extraction ; Cornea ; Corneal Diseases ; Corneal Transplantation* ; Epidemiologic Studies* ; Eye Banks ; Humans ; Keratitis ; Keratoplasty, Penetrating ; Korea* ; Surveys and Questionnaires ; Tissue Donors ; Transplants