Assessing maternity care access: impacts on cesarean sections and dystocia.

BACKGROUND: As South Korea grapples with a declining birthrate, maternity care accessibility has become challenging. This study examines the association with labour intervention and pregnancy complication, specifically focusing on C-section and dystocia in maternity disparities. METHODS: Data from the South Korean NHIS-NID was used to analyze 1,437,186 women with childbirths between 2010 and 2015. The research defines 50 specific districts as Obstetrically Underserved Areas produced by the Ministry of Health and Welfare in 2011. C-Section were assessed through using medical procedure and DRG codes, while dystocia was defined using ICD-10 code. Logistic regression analysis was used to examine the significance of the association. RESULTS: Among the population residing in underserved areas, 42,873 out of a total of 1,437,186 individuals were identified. For nationwide cases, the odds ratios (ORs) for C-Section were 1.11 (95% CI: 1.08-1.13) and dystocia were 1.07 (95% CI: 1.05-1.09). In relatively accessible urban areas, the ORs for C-Section and dystocia, based on whether they were obstetrically underserved areas, were 1.16 (95% CI: 1.13-1.18) and 1.10 (95% CI: 1.08-1.19), respectively. CONCLUSION: Poor accessibility to maternity care facilities is closely linked to high-risk pregnancies, including an increased incidence of dystocia and a higher rate of C-sections. Insufficient access to maternity care not only raises the risk of serious pregnancy complications. Consequently, there is a pressing need for multi-faceted efforts to bridge this disparity.

Increased Risk of New-Onset Parkinson's Disease Following a Diagnosis of Retinal Vascular Occlusion: A 14-Year Cohort Study.

BACKGROUND: Although the role of the vascular component in the pathophysiology of Parkinson's disease is widely accepted and retinal vascular abnormalities are commonly observed in Parkinson's disease patients, evidence connecting retinal vascular disorders with the risk of developing Parkinson's disease is limited. We aimed to investigate the association between retinal vascular occlusion (RVO) and the risk of developing Parkinson's disease in people over 60 years using a nationwide cohort. METHODS: From the 14-year South Korean National Health Insurance Service-Senior cohort, 11 210 incident RVO patients and 11 210 propensity scores, risk-matched controls were included. The incidence of Parkinson's disease was estimated with a Poisson regression. A Cox proportional hazards regression model was used to investigate the associations between RVO and the risk of Parkinson's disease. RESULTS: The incidence of Parkinson's disease was 664.4 cases per 100 000 person-years (95% confidence interval [CI], 599.7-736.0) in the RVO cohort. Individuals with RVO had an increased incidence of Parkinson's disease (hazard ratio [HR], 1.28; 95% CI: 1.10-1.49). Increased PD risk was predominantly observed in retinal artery occlusion patients (HR, 1.53; 95% CI: 1.11-2.12), male patients (HR, 1.67; 95% CI: 1.29-2.17), and 5 years after diagnosis (HR, 1.46; 95% CI: 1.10-1.93). CONCLUSIONS: Our findings suggest that a common pathophysiological pathway, such as vasculature changes, may exist between RVO and Parkinson's disease. RVO may be one of the risk factors associated with future development of Parkinson's disease. The nature of this association warrants further investigation.

Estimating the Epidemic Size of Superspreading Coronavirus Outbreaks in Real Time: Quantitative Study.

BACKGROUND: Novel coronaviruses have emerged and caused major epidemics and pandemics in the past 2 decades, including SARS-CoV-1, MERS-CoV, and SARS-CoV-2, which led to the current COVID-19 pandemic. These coronaviruses are marked by their potential to produce disproportionally large transmission clusters from superspreading events (SSEs). As prompt action is crucial to contain and mitigate SSEs, real-time epidemic size estimation could characterize the transmission heterogeneity and inform timely implementation of control measures. OBJECTIVE: This study aimed to estimate the epidemic size of SSEs to inform effective surveillance and rapid mitigation responses. METHODS: We developed a statistical framework based on back-calculation to estimate the epidemic size of ongoing coronavirus SSEs. We first validated the framework in simulated scenarios with the epidemiological characteristics of SARS, MERS, and COVID-19 SSEs. As case studies, we retrospectively applied the framework to the Amoy Gardens SARS outbreak in Hong Kong in 2003, a series of nosocomial MERS outbreaks in South Korea in 2015, and 2 COVID-19 outbreaks originating from restaurants in Hong Kong in 2020. RESULTS: The accuracy and precision of the estimation of epidemic size of SSEs improved with longer observation time; larger SSE size; and more accurate prior information about the epidemiological characteristics, such as the distribution of the incubation period and the distribution of the onset-to-confirmation delay. By retrospectively applying the framework, we found that the 95% credible interval of the estimates contained the true epidemic size after 37% of cases were reported in the Amoy Garden SARS SSE in Hong Kong, 41% to 62% of cases were observed in the 3 nosocomial MERS SSEs in South Korea, and 76% to 86% of cases were confirmed in the 2 COVID-19 SSEs in Hong Kong. CONCLUSIONS: Our framework can be readily integrated into coronavirus surveillance systems to enhance situation awareness of ongoing SSEs.

Increased Risk of Dementia Following a Diagnosis of Hearing Impairment: A South Korean Nationwide Cohort Study.

BACKGROUND: Among the older adults, hearing impairment is a common problem and may contribute to dementia. OBJECTIVE: Therefore, we aimed to examine the association between hearing impairment and the risk of dementia among older adults in South Korea. METHODS: Using the Korean National Health Insurance Service-Senior Cohort from 2005 to 2019, we collected data of 44,728 patients. Hearing impairment was determined using the national disability registry. Propensity score matching (1:1) was performed to match patients with and without hearing impairment (case: 22,364, control: 22,364). A Cox proportional hazards regression model was built to analyze the association between hearing impairment and dementia. RESULTS: Patients with hearing impairment had a higher risk of dementia than those without hearing impairment (hazard ratio [HR] = 1.28, 95% confidence interval [CI] = 1.23-1.34). Assessing the degree of disability, both severe (HR = 1.25, 95% CI = 1.16-1.35) and mild conditions (HR = 1.29, 95% CI = 1.23-1.35) had an increased risk of dementia, respectively. CONCLUSIONS: Older patients with hearing impairment exhibit an increased risk of dementia, thereby warranting a new approach to dementia care among these patients regardless of the degree of hearing impairment.

Effectiveness of COVID-19 vaccines against severe outcomes in cancer patients: Real-world evidence from self-controlled risk interval and retrospective cohort studies.

BACKGROUND: The effectiveness of COVID-19 vaccines is generally reduced in cancer patients compared to the general population. However, there are only a few studies that compare the relative risk of breakthrough infections and severe COVID-19 outcomes in fully vaccinated cancer patients versus their unvaccinated counterparts. METHODS: To assess the effectiveness of COVID-19 vaccines in cancer patients, we employed (1) a self-controlled risk interval (SCRI) design, and (2) a retrospective matched cohort design. A SCRI design was used to compare the risk of breakthrough infection in vaccinated cancer patients during the period immediately following vaccination ("control window") and the period in which immunity is achieved ("exposure windows"). The retrospective matched cohort design was used to compare the risk of severe COVID-19 outcomes between vaccinated and unvaccinated cancer patients. For both studies, data were extracted from the Korea Disease Control and Prevention Agency-COVID-19-National Health Insurance Service cohort, including demographics, medical history, and vaccination records of all individuals confirmed with COVID-19. We used conditional Poisson regression to calculate the incidence rate ratio (IRR) for breakthrough infection and Cox regression to estimate the hazard ratio (HR) for severe outcomes. RESULTS: Of 14,448 cancer patients diagnosed with COVID-19 between October 2020 and December 2021, a total of 217 and 3996 cancer patients were included in the SCRI and cohort study respectively. While the risk of breakthrough infections, measured by the incidence rate in the control and exposure windows, did not show statistically significant difference in vaccinated cancer patients (IRR=0.88, 95% CI: 0.64-1.22), the risk of severe COVID-19 outcomes was significantly lower in vaccinated cancer patients compared to those unvaccinated (HR=0.27, 95% CI: 0.22-0.34). CONCLUSION: COVID-19 vaccines significantly reduce the risk of severe outcomes in cancer patients, though their efficacy against breakthrough infections is less evident.

Association between smartphone addiction risk, sleep quality, and sleep duration among Korean school-age children: a population-based panel study.

Smartphone addiction is regarded as a public health threat to the lives of children and adolescents. However, its association with sleep quality and quantity is poorly understood in the Korean context. This study investigated the association between smartphone addiction, sleep quality, and sleep duration among Korean school-age children. Our study employed data from the Korean Children and Youth Panel Survey of 2018-2019, which included 4287 participants. Smartphone addiction was assessed using the Smartphone Addiction Proneness Scale. A generalized estimating equation model was used to analyze the data. Children in the high-risk group showed an increased likelihood of poor sleep quality compared to those in the low-risk group (odds ratio (OR) = 1.59, confidence interval (CI) [1.06-2.38]). Children in the potential-risk and high-risk groups showed an increased likelihood of short sleep duration compared to those in the low-risk group (potential-risk: OR = 1.44, CI [1.09-1.90]; high-risk: OR = 2.25, CI [1.66-3.05]) Children who are at high risk for smartphone addiction are likely to have poor sleep quality and short sleep duration. Therefore, appropriate interventions and continuous monitoring are required to protect children from smartphone addiction and improve their sleep quality and duration.