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Depression is a complex mental health disorder with highly heterogeneous symptoms that vary significantly across individuals, influenced by various factors, including sex and regional contexts. Network analysis is an analytical method that provides a robust framework for evaluating the heterogeneity of depressive symptoms and identifying their potential clinical implications.
Objective:
To investigate sex-specific differences in the network structures of depressive symptoms in Asian patients diagnosed with depressive disorders, using data from the Research on Asian Psychotropic Prescription Patterns for Antidepressants, Phase 3, which was conducted in 2023.
Methods:
A network analysis of 10 depressive symptoms defined according to the National Institute for Health and Care Excellence guidelines was performed. The sex-specific differences in the network structures of the depressive symptoms were examined using the Network Comparison Test. Subgroup analysis of the sex-specific differences in the network structures was performed according to geographical region classifications, including East Asia, Southeast Asia, and South or West Asia.
Results:
A total of 998 men and 1,915 women with depression were analysed in this study. The analyses showed that all 10 depressive symptoms were grouped into a single cluster. Low self-confidence and loss of interest emerged as the most central nodes for men and women, respectively. In addition, a significant difference in global strength invariance was observed between the networks. In the regional subgroup analysis, only East Asian men showed two distinct clustering patterns. In addition, significant differences in global strength and network structure were observed only between East Asian men and women.
Conclusion:
The study highlights the sex-specific differences in depressive symptom networks across Asian countries. The results revealed that low self-confidence and loss of interest are the main symptoms of depression in Asian men and women, respectively. The network connections were more localised in men, whereas women showed a more diverse network. Among the Asian subgroups analysed, only East Asians exhibited significant differences in network structure. The considerable effects of neurovegetative symptoms in men may indicate potential neurobiological underpinnings of depression in the East Asian population.
Patients with schizophrenia experience accelerated aging, accompanied by abnormalities in biomarkers such as shorter telomere length. Brain age prediction using neuroimaging data has gained attention in schizophrenia research, with consistently reported increases in brain-predicted age difference (brain-PAD). However, its associations with clinical symptoms and illness duration remain unclear.
Methods
We developed brain age prediction models using structural magnetic resonance imaging (MRI) data from 10,938 healthy individuals. The models were validated on an independent test dataset comprising 79 healthy controls, 57 patients with recent-onset schizophrenia, and 71 patients with chronic schizophrenia. Group comparisons and the clinical associations of brain-PAD were analyzed using multiple linear regression. SHapley Additive exPlanations (SHAP) values estimated feature contributions to the model, and between-group differences in SHAP values and group-by-SHAP value interactions were also examined.
Results
Patients with recent-onset schizophrenia and chronic schizophrenia exhibited increased brain-PAD values of 1.2 and 0.9 years, respectively. Between-group differences in SHAP values were identified in the right lateral prefrontal area (false discovery rate [FDR] p = 0.022), with group-by-SHAP value interactions observed in the left prefrontal area (FDR p = 0.049). A negative association between brain-PAD and Full-scale Intelligence Quotient scores in chronic schizophrenia was noted, which did not remain significant after correction for multiple comparisons.
Conclusions
Brain-PAD increases were pronounced in the early phase of schizophrenia. Regional brain abnormalities contributing to brain-PAD likely vary with illness duration. Future longitudinal studies are required to overcome limitations related to sample size, heterogeneity, and the cross-sectional design of this study.
Comorbid depression substantially affects the management of glycemia and diabetes-related complications among patients with type 2 diabetes mellitus. In this study, we sought to determine the association between weight change over 4 years and depression risk among patients with type 2 diabetes mellitus.
Methods
This population-based retrospective cohort study from the National Health Insurance Services of Korea included 1 111 345 patients with type 2 diabetes who were divided into groups according to body weight change over 4 years. Body weight changes were compared with the preceding 4-year period (2005–2008). Depression was defined according to the International Classification of Diseases 10th revision code for depression (F32 and F33) on one or more inpatient or outpatient claims.
Results
During a median follow-up of 7.4 years, 244 081 cases of depression were identified. We observed a U-shaped association between body weight change and depression risk with a higher risk among both groups of weight loss (hazard ratio (HR) 1.17, 95% CI 1.15–1.19 for ⩾ −10%; HR 1.07, 95% CI 1.06–1.08 for −10 to −5%) and weight gain (HR 1.06, 95% CI 1.04–1.08 for ⩾10%; HR 1.02, 95% CI 1.01–1.04 for 5–10%) compared with the stable weight group (−5 to 5%).
Conclusions
A U-shaped association between body weight change and depression risk was observed in this large nationwide cohort study. Our study suggests that patients with type 2 diabetes and weight change, either gain or loss, could be considered a high-risk group for depression.
The “Fast track” protocol is an early extubation strategy to reduce ventilator-associated complications and induce early recovery after open-heart surgery. This study compared clinical outcomes between operating room extubation and ICU extubation after open-heart surgery in patients with CHD.
Methods:
We retrospectively reviewed 215 patients who underwent open-heart surgery for CHDs under the scheduled “Fast track” protocol between September 2016 and April 2022. The clinical endpoints were post-operative complications, including bleeding, respiratory and neurological complications, and hospital/ICU stays.
Results:
The patients were divided into operating room extubation (group O, n = 124) and ICU extubation (group I, n=91) groups. The most frequently performed procedures were patch closures of the atrial septal (107/215, 49.8%) and ventricular septal (89/215, 41.4%) defects. There were no significant differences in major post-operative complications or ICU and hospital stay duration between the two groups; however, patients in group I showed longer mechanical ventilatory support (0.0 min vs. 59.0 min (interquartile range: 17.0–169.0), p < 0.001). Patients in Group O showed higher initial lactate levels (3.2 ± 1.7 mg/dL versus 2.5 ± 2.0 mg/dL, p = 0.007) and more frequently used additional sedatives and opioid analgesics (33.1% versus 19.8%, p = 0.031).
Conclusions:
Extubation in the operating room was not beneficial for patients during post-operative ICU or hospital stay. Early extubation in the ICU resulted in more stable hemodynamics in the immediate post-operative period and required less use of sedatives and analgesics.
Background: SARS-CoV-2 infection of healthcare workers (HCWs) occasionally occurs via acquisition from their colleagues. Data regarding the infection rates of HCWs with close contact and non–close contacts of HCWs are limited. In addition, the protective effect of COVID-19 vaccination against transmission between HCWs is unknown. We evaluated the infection rates of HCWs with close contact and non–close contact of infected HCWs and the effect of COVID-19 vaccination on transmission among HCWs in a tertiary-care hospital in South Korea. Methods: This study was performed in a tertiary-care hospital in Korea. We analyzed the COVID-19 cases and contacts among HCWs from January to December 2021. We reviewed the vaccination status of confirmed and exposed HCWs, the type of vaccination, and the infection rate according to the contact. We performed subgroup analyses in individuals who had been diagnosed since July 2021 when the δ (delta) variant became the dominant strain in South Korea. Transmission was defined based on their spatiotemporal epidemiologic association. Results: During the study period, 173 HCWs had COVID-19, and 2,693 HCWs were exposed to them. Among them, 18 (1.52%) of 1,186 close contacts and 13 (0.86%) of 1,507 non–close contacts had a positive SARS-CoV-2 test (P = .11). When the index cases had been fully vaccinated, the infection rate of close contacts was 0.85% (7 of 820), whereas the infection rate of close contacts was 3.01% (11 of 366) when the index had not been fully vaccinated (P = .005). However, the infection rate of non–close contacts was not different according to the vaccination status of index (0.83% vs 0.89%; P = .90). During the period of δ (delta) variant being dominant, the infection rate of close contacts was significantly lower when the index case had been fully vaccinated index than in cases with a non–fully vaccinated index case (0.85% vs 5.88%; P < .001). Conclusions: Transmission to colleagues was significantly lower from vaccinated HCWs than from nonvaccinated HCWs, and this finding was more significant in the era of the δ (delta) variant. Our findings support the importance of vaccination in HCWs.
We quantitatively assessed the fit failure rate of N95 respirators according to the number of donning/doffing and hours worn.
Design:
Experimental study.
Setting:
A tertiary-care referral center in South Korea.
Participants:
In total, 10 infection control practitioners participated in the fit test.
Methods:
The first experiment comprised 4 consecutive 1-hour donnings and fit tests between each donning. The second experiment comprised 2 consecutive 3-hour donnings and fit tests between each donning. The final experiment comprised fit tests after an 1-hour donning or a 2-hour donning.
Results:
For 1-hour donnings, 60%, 70%, and 90% of the participants had fit failures after 2, 3, and 4 consecutive donnings, respectively. For 3-hour donnings, 50% had fit failure after the first donning and 70% had failures after 2 consecutive donnings. All participants passed the fit test after refitting whenever fit failure occurred. The final experiment showed that 50% had fit failure after a single use of 1 hour, and 30% had fit failure after a single use of 2 hours.
Conclusions:
High fit-failure rates were recorded after repeated donning and extended use of N95 respirators. Caution is needed for reuse (≥1 time) and extended use (≥1 hour) of N95 respirators in high-risk settings such as those involving aerosol-generating procedures. Although adequate refitting may recover the fit factor, the use of clean gloves and strict hand hygiene afterward should be ensured when touching the outer surfaces of N95 respirators for refitting.
Early replacement of a new central venous catheter (CVC) may pose a risk of persistent or recurrent infection in patients with a catheter-related bloodstream infection (CRBSI). We evaluated the clinical impact of early CVC reinsertion after catheter removal in patients with CRBSIs.
Methods:
We conducted a retrospective chart review of adult patients with confirmed CRBSIs in 2 tertiary-care hospitals over a 7-year period.
Results:
To treat their infections, 316 patients with CRBSIs underwent CVC removal. Among them, 130 (41.1%) underwent early CVC reinsertion (≤3 days after CVC removal), 39 (12.4%) underwent delayed reinsertion (>3 days), and 147 (46.5%) did not undergo CVC reinsertion. There were no differences in baseline characteristics among the 3 groups, except for nontunneled CVC, presence of septic shock, and reason for CVC reinsertion. The rate of persistent CRBSI in the early CVC reinsertion group (22.3%) was higher than that in the no CVC reinsertion group (7.5%; P = .002) but was similar to that in the delayed CVC reinsertion group (17.9%; P > .99). The other clinical outcomes did not differ among the 3 groups, including rates of 30-day mortality, complicated infection, and recurrence. After controlling for several confounding factors, early CVC reinsertion was not significantly associated with persistent CRBSI (OR, 1.59; P = .35) or 30-day mortality compared with delayed CVC reinsertion (OR, 0.81; P = .68).
Conclusions:
Early CVC reinsertion in the setting of CRBSI may be safe. Replacement of a new CVC should not be delayed in patients who still require a CVC for ongoing management.
To evaluate the bidirectional relationship between blood pressure (BP) and depressive symptoms using a large prospective cohort study.
Methods
Prospective cohort study was performed in 276 244 adults who participated in a regular health check-up and were followed annually or biennially for up to 5.9 years. BP levels were categorised according to the 2017 American College of Cardiology and American Heart Association hypertension guidelines. Depressive symptoms were assessed using Centre for Epidemiologic Studies-Depression (CESD) questionnaire and a cut-off score of ≥25 was regarded as case-level depressive symptoms.
Results
During 672 603.3 person-years of follow-up, 5222 participants developed case-level depressive symptoms. The multivariable-adjusted hazard ratios (HRs) [95% confidence interval (CI)] for incident case-level depressive symptoms comparing hypotension, elevated BP, hypertension stage 1 and hypertension stage 2 to normal BP were 1.07 (0.99–1.16), 0.93 (0.82–1.05), 0.89 (0.81–0.97) and 0.81 (0.62–1.06), respectively (p for trend <0.001). During 583 615.3 person-years of follow-up, 27 787 participants developed hypertension. The multivariable-adjusted HRs (95% CI) for incident hypertension comparing CESD 16–24 and ⩾25 to CESD < 16 were 1.05 (1.01–1.11) and 1.12 (1.03–1.20), respectively (p for trend <0.001) and in the time-dependent models, corresponding HRs (95% CI) were 1.12 (1.02–1.24) and 1.29 (1.10–1.50), respectively (p for trend <0.001).
Conclusions
In this large cohort study of young and middle-aged individuals, higher BP levels were independently associated with a decreased risk for developing case-level depressive symptoms and depressive symptoms were also associated with incident hypertension. Further studies are required to elucidate the mechanisms underlying the bidirectional association between BP levels and incident depression.
We present the derived kinematic characteristics of low-α thin-disk and high-α thick-disk stars in the Milky Way, investigated with a sample of about 32,000 G- and K-type dwarfs from the Sloan Extension for Galactic Understanding and Exploration (SEGUE). Based on the level of α-element enhancement as a function of [Fe/H], we separate our sample into thin- and thick-disk stars and then derive mean velocities, velocity dispersions, and velocity gradients for the U, V, and W velocity components, respectively, as well as the orbital eccentricity distribution. There are notable gradients in the V velocity over [Fe/H] in both populations: −23 km s−1 dex−1 for the thin disk and +44 km s−1 dex−1 for the thick disk. The velocity dispersion of the thick disk decreases with increasing [Fe/H], while the velocity dispersion gradient over [Fe/H] for the thin disk is almost flat for all velocity components, except for the W velocity dispersion of the metal-poor thin-disk stars. The eccentricity distribution exhibits a peak at a higher value, and is more symmetric as [α/Fe] increases, implying that complex formation mechanisms may be involved. Our results can be used to constrain several proposed disk-formation scenarios of the Milky Way and other large spirals.
The Saemangeum tidal flat, an important staging site for migratory shorebirds that travel the East Asian-Australasian (EAA) Flyway, was isolated from the eastern Yellow Sea in 2006 as part of a large-scale reclamation project. To gain a better understanding of the impacts that this reclamation has had on the long-distance migratory shorebirds that use the EAA Flyway, we examined the number of shorebirds visiting Saemangeum and three adjacent sites in the Geum Estuary (Yubu Island, the Janghang coastline, and the Geum River Channel) during the spring and fall prior to, and after, completion of the reclamation (2004–2013). A total of 48 shorebird species, including one Critically Endangered, three Endangered, and nine Near Threatened species, were observed over this period. Peak numbers of shorebirds recorded at sites in Saemangeum and the Geum Estuary following completion of the project were 74% below those recorded in 2004 and 2005, the years prior to reclamation activity. In Saemangeum, shorebird abundance declined by approximately 95% and 97.3% during the northward and southward migrations, respectively, as a result of reclamation. Although shorebird populations in the Geum Estuary increased by 5% and 20% during the northwards and southward migrations, respectively, these increases failed to offset the reduction in shorebird abundance in Saemangeum; overall, shorebird abundance at Saemangeum and the three adjacent sites in the Geum Estuary markedly declined over the reclamation period. Given the more favourable conditions of adjacent areas, sites in Saemangeum and the Geum Estuary no longer provide the habitat conditions necessary for long-distance migratory shorebirds. In order to improve habitat for staging migratory birds, we suggest that measures such as the conversion of an abandoned salt farm for use as roosting sites, the construction of artificial barriers to prevent human disturbance, and re-opening of the river-banks to facilitate water flow be implemented.
This study aimed to investigate the relationship between the unemployment experience and depressive symptoms among mid-aged (ages 45–59) and elderly (ages 60 or above) persons and to examine further the effects of unemployment insurance, industrial accident compensation insurance (IACI) and national pension on the stated relationship. Data were used from the Korean Longitudinal Study of Aging (KLoSA) between 2006 and 2012. A total of 1,536 individuals employed at the 2006 baseline were followed. The association between employment status change during 2006 to 2008, 2008 to 2010 or 2010 to 2012 and depressive symptoms in years 2008, 2010 or 2012 were analysed using a generalised estimating equation model. Depressive symptoms were measured with the Center for Epidemiological Studies Depression Scale (CES-D 10) scale. The results showed that the ‘employed to unemployed’ group had statistically significant increases in depression scores in the mid-aged (β = 0.4884, p = 0.0038) and elderly (β = 0.8275, p ⩽ 0.0001) categories, compared to the ‘employed to employed’ group. Findings were maintained in groups without a social safety net. Contrastingly, the ‘employed to unemployed’ groups with unemployment insurance and IACI did not show statistically significant increases in depression scores. The ‘employed to unemployed’ category of individuals enrolled in the national pension system exhibited a lower increase of depression. Therefore, an enhanced focus on the mental health of unemployed individuals is required, in addition to the provision of a reliable social safety net.
Personality may predispose family caregivers to experience caregiving differently in similar situations and influence the outcomes of caregiving. A limited body of research has examined the role of some personality traits for health-related quality of life (HRQoL) among family caregivers of persons with dementia (PWD) in relation to burden and depression.
Methods:
Data from a large clinic-based national study in South Korea, the Caregivers of Alzheimer's Disease Research (CARE), were analyzed (N = 476). Path analysis was performed to explore the association between family caregivers’ personality traits and HRQoL. With depression and burden as mediating factors, direct and indirect associations between five personality traits and HRQoL of family caregivers were examined.
Results:
Results demonstrated the mediating role of caregiver burden and depression in linking two personality traits (neuroticism and extraversion) and HRQoL. Neuroticism and extraversion directly and indirectly influenced the mental HRQoL of caregivers. Neuroticism and extraversion only indirectly influenced their physical HRQoL. Neuroticism increased the caregiver's depression, whereas extraversion decreased it. Neuroticism only was mediated by burden to influence depression and mental and physical HRQoL.
Conclusions:
Personality traits can influence caregiving outcomes and be viewed as an individual resource of the caregiver. A family caregiver's personality characteristics need to be assessed for tailoring support programs to get the optimal benefits from caregiver interventions.
The HoDoo English game was developed to take advantage of the benefits attributed to on-line games while teaching English to native Korean speakers. We expected to see that the improvements in the subjects’ English language abilities after playing the HoDoo English game would be associated with increased brain functional connectivity in the areas of the brain involved in the language production (Broca’s area) and the understanding (Wernicke’s area) networks. Twelve children, aged nine and ten, were asked to play the on-line English education game for 50 minutes per day, five days per week for twelve weeks. At baseline, and again at the end of twelve weeks of game play, each child’s English language ability was assessed and a functional magnetic resonance imaging (fMRI) scan was conducted. The on-line English education game play effectively improved English language skills, especially in terms of non-verbal pragmatic skills. Following twelve weeks of on-line English education game play, the children showed positive connectivity between Broca’s area and the left frontal cortex as well as between Wernicke’s area and the left parahippocampal gyrus and the right medial frontal gyrus. Changes in pragmatic scores were positively correlated with average peak brain activity in the left parahippocampal gyrus. To the best of our knowledge, this is the first study to report an improvement in English ability and changes in brain activity within language areas after on-line language education game play.
The Sewol ferry disaster is one of the most tragic events in Korea’s modern history. Among the 476 people on board, which included Danwon High School students (324) and teachers (14), 304 passengers died in the disaster (295 recovered corpses and 9 missing) and 172 survived. Of the rescued survivors, 72 were attending Danwon High School, located in Ansan City, and residing in a residence nearby. Because the students were young, emotionally susceptible adolescents, both the government and the parents requested the students be grouped together at a single hospital capable of appropriate psychiatric care. Korea University Ansan Hospital was the logical choice, as the only third-tier university-grade hospital with the necessary faculty and facilities within the residential area of the families of the students. We report the experiences and the lessons learned from the processes of preparing for and managing the surviving young students as a community-based hospital. (Disaster Med Public Health Preparedness. 2017;11:389–393)
Polycyclic aromatic hydrocarbons (PAH) are common dietary exposures that cross the human placenta and are classified as a probable human carcinogen. The aim of the present study was to investigate the potential impact of exposure to PAH-containing meat consumed during pregnancy on birth outcomes.
Design
Prospective birth cohort study. Only non-smoking women with singleton pregnancies, who were free from chronic disease such as diabetes and hypertension, were included in the study. Maternal consumption of PAH-rich meat was estimated through FFQ. Multiple linear regression was used to assess factors related to higher intake and the association between dietary PAH and birth outcomes.
Setting
Republic of Korea, 2006–2011.
Subjects
Pregnant women (n 778) at 12–28 weeks of gestation enrolled in the Mothers and Children’s Environmental Health (MOCEH) study.
Results
The multivariable regression model showed a significant reduction in birth weight associated with higher consumption level of foods rich in PAH, such as grilled or roasted meat, during pregnancy (β=−17·48 g, P<0·05 for every 1 point higher in meat score). Further adjusting for biomarkers of airborne PAH did not alter this association. There was no evidence that higher consumption level of PAH-rich meat shortens the duration of gestation (P=0·561). Regression models performed for birth length and head circumference produced negative effects that were not statistically significant.
Conclusions
Consumption of higher levels of barbecued, fried, roasted and smoked meats during pregnancy was associated with reduced birth weight. Dietary risk of PAH exposure in Korean women is of concern.
The occurrence of a relapse during abstinence is an important issue that must be addressed during treatment for drug addiction. We investigated the influence of drug exposure pattern on morphine-seeking behaviour following withdrawal. We also studied the role of the hippocampus in this process to confirm its involvement in drug relapse.
Methods
Male Sprague–Dawley rats that were trained to self-administer morphine (1.0 mg/kg) using 2, 4, 6, 8, or 10 h daily sessions underwent withdrawal in their home cages and were re-exposed to the operant chamber to evaluate morphine-seeking behaviour. During the relapse session, rats were intravenously injected with morphine (0.25 mg/kg) or saline before re-exposure to the chamber. In the second experiment, rats were administered a microinjection of saline or cobalt chloride (CoCl2, 1 mM), a synaptic blocker, into the CA1 of the hippocampus prior to the relapse test.
Results
In the first experiment, more morphine-seeking behaviour was observed in the 2 h group (animals trained to self-administer morphine during a 2 h daily session spread over 21 days) during the relapse session, despite all groups being exposed to similar amounts of morphine during the training period before withdrawal. In the second experiment, pretreatment with CoCl2 markedly reduced morphine-seeking behaviour in the 2 h group.
Conclusions
The present findings suggest that the exposure pattern influences the degree of relapse and that control of memorisation is important for prevention of relapse.