Risk of Severe COVID-19 and Protective Effectiveness of Vaccination Among Solid Organ Transplant Recipients.

BACKGROUND: Solid organ transplant recipients (SOTRs) are at higher risk for severe infection. However, the risk for severe COVID-19 and vaccine effectiveness among SOTRs remain unclear. METHODS: This retrospective study used a nationwide health care claims database and COVID-19 registry from the Republic of Korea (2020 to 2022). Adult SOTRs diagnosed with COVID-19 were matched with up to 4 non-SOTR COVID-19 patients by propensity score. Severe COVID-19 was defined as treatment with high-flow nasal cannulae, mechanical ventilation, or extracorporeal membrane oxygenation. RESULTS: Among 6783 SOTRs with COVID-19, severe COVID-19 was reported with the highest rate in lung transplant recipients (13.16%), followed by the heart (6.30%), kidney (3.90%), and liver (2.40%). SOTRs had a higher risk of severe COVID-19 compared to non-SOTRs, and lung transplant recipients showed the highest risk (adjusted odds ratio, 18.14; 95% confidence interval [CI], 8.53-38.58). Vaccine effectiveness against severe disease among SOTRs was 47% (95% CI, 18%-65%), 64% (95% CI, 49%-75%), and 64% (95% CI, 29%-81%) for 2, 3, and 4 doses, respectively. CONCLUSIONS: SOTRs are at significantly higher risk for severe COVID-19 compared to non-SOTRs. Vaccination is effective in preventing the progression to severe COVID-19. Efforts should be made to improve vaccine uptake among SOTRs, while additional protective measures should be developed.

Risk of Ischemic Heart Disease in Patients With Postpancreatectomy Diabetes and Pancreatic Cancer: A Population-Based Study.

BACKGROUND: Postpancreatectomy diabetes can be caused by resection of functioning pancreatic tissue and is associated with postoperative pancreatic islet cell mass loss and subsequent endocrine dysfunction. Diabetes is a well-known risk factor for ischemic heart disease. However, no previous studies have investigated ischemic heart disease in patients with postpancreatectomy diabetes and pancreatic cancer. METHODS AND RESULTS: Rates of patients with diabetes diagnosed with pancreatic cancer who underwent pancreatectomy between 2002 and 2019 in South Korea were obtained from the Korean National Health Insurance Service database. Patient-level propensity score matching was conducted to reduce the possibility of selection bias, and multivariate Cox proportional hazards models were used to determine the association between postpancreatectomy diabetes and ischemic heart disease. In total, 30 242 patients were initially enrolled in the study. After applying exclusion criteria and propensity score matching, 2952 patients were included in the comparative analysis between the postpancreatectomy group with diabetes and the group without diabetes. Patients in the postpancreatectomy group with diabetes had significantly higher rates of ischemic heart disease than those in the group without diabetes. In total, 3432 patients were included in the comparison between the postpancreatectomy and prepancreatectomy groups with diabetes. There was no significant difference in the risk of ischemic heart disease between the postpancreatectomy and prepancreatectomy groups with diabetes. CONCLUSIONS: Patients who developed diabetes after pancreatectomy had a higher risk of ischemic heart disease than patients who did not develop diabetes after pancreatectomy, and the rate of ischemic heart disease in these patients was similar to that in patients preoperatively diagnosed with diabetes.

Lack of association between fluoroquinolone and aortic aneurysm or dissection.

BACKGROUND AND AIMS: An increased risk of aortic aneurysm and aortic dissection (AA/AD) has been reported with fluoroquinolone (FQ) use. However, recent studies suggested confounding factors by indication. This study aimed to investigate the risk of AA/AD associated with FQ use. METHODS: This nationwide population-based study included adults aged ≥20 years who received a prescription of oral FQ or third-generation cephalosporins (3GC) during outpatient visits from 2005 to 2016. Data source was the National Health Insurance Service reimbursement database. The primary outcome was hospitalization or in-hospital death with a primary diagnosis of AA/AD. A self-controlled case series (SCCS) and Cox proportional hazards model were used. Self-controlled case series compared the incidence of the primary outcome in the risk period vs. the control periods. RESULTS: A total of 954 308 patients (777 109 with FQ and 177 199 with 3GC use) were included. The incidence rate ratios for AA/AD between the risk period and the pre-risk period were higher in the 3GC group [11.000; 95% confidence interval (CI) 1.420-85.200] compared to the FQ group (2.000; 95% CI 0.970-4.124). The overall incidence of AA/AD among the patients who received FQ and 3GC was 5.40 and 8.47 per 100 000 person-years. There was no significant difference in the risk between the two groups (adjusted hazard ratio 0.752; 95% CI 0.515-1.100) in the inverse probability of treatment-weighted Cox proportional hazards model. Subgroup and sensitivity analysis showed consistent results. CONCLUSIONS: There was no significant difference in the risk of AA/AD in patients who were administered oral FQ compared to those administered 3GC. The study findings suggest that the use of FQ should not be deterred when clinically indicated.

Antibiotic Prescription in Patients With Coronavirus Disease 2019: Analysis of National Health Insurance System Data in the Republic of Korea.

BACKGROUND: Although coronavirus disease 2019 (COVID-19) is a viral infection, antibiotics are often prescribed due to concerns about accompanying bacterial infection. Therefore, we aimed to analyze the number of patients with COVID-19 who received antibiotic prescriptions, as well as factors that influenced antibiotics prescription, using the National Health Insurance System database. METHODS: We retrospectively reviewed claims data for adults aged ≥ 19 years hospitalized for COVID-19 from December 1, 2019 to December 31, 2020. According to the National Institutes of Health guidelines for severity classification, we calculated the proportion of patients who received antibiotics and the number of days of therapy per 1,000 patient-days. Factors contributing to antibiotic use were determined using linear regression analysis. In addition, antibiotic prescription data for patients with influenza hospitalized from 2018 to 2021 were compared with those for patients with COVID-19, using an integrated database from Korea Disease Control and Prevention Agency-COVID19-National Health Insurance Service cohort (K-COV-N cohort), which was partially adjusted and obtained from October 2020 to December 2021. RESULTS: Of the 55,228 patients, 46.6% were males, 55.9% were aged ≥ 50 years, and most patients (88.7%) had no underlying diseases. The majority (84.3%; n = 46,576) were classified as having mild-to-moderate illness, with 11.2% (n = 6,168) and 4.5% (n = 2,484) having severe and critical illness, respectively. Antibiotics were prescribed to 27.3% (n = 15,081) of the total study population, and to 73.8%, 87.6%, and 17.9% of patients with severe, critical, and mild-to-moderate illness, respectively. Fluoroquinolones were the most commonly prescribed antibiotics (15.1%; n = 8,348), followed by third-generation cephalosporins (10.4%; n = 5,729) and beta-lactam/beta-lactamase inhibitors (6.9%; n = 3,822). Older age, COVID-19 severity, and underlying medical conditions contributed significantly to antibiotic prescription requirement. The antibiotic use rate was higher in the influenza group (57.1%) than in the total COVID-19 patient group (21.2%), and higher in severe-to-critical COVID-19 cases (66.6%) than in influenza cases. CONCLUSION: Although most patients with COVID-19 had mild to moderate illness, more than a quarter were prescribed antibiotics. Judicious use of antibiotics is necessary for patients with COVID-19, considering the severity of disease and risk of bacterial co-infection.

Severe coronavirus disease 2019 in pediatric solid organ transplant recipients: Big data convergence study in Korea (K-COV-N cohort).

OBJECTIVES: The risk of severe COVID-19 in children with a solid organ transplant (SOT) is not well established. We compare the relative risk of severe COVID-19 infection between pediatric SOT and non-SOT children. METHODS: The newly constructed K-COV-N cohort (Korea Disease Control and Prevention Agency-COVID-19-National Health Insurance Service) was used. Children with COVID-19 (<18 years old) who underwent SOT between January 2008 to January 2022 were included. Non-SOT children with COVID-19 were selected in a ratio of 1:4 using propensity score matching. Three definitions of severe COVID-19 were established based on their requirement for respiratory support: severe I (requiring respiratory support above a high-flow nasal cannula or prolonged hospitalization ≥6 days), severe II (requiring any oxygen supplement), and severe III (requiring any oxygen supplement or prolonged hospitalization ≥6 days). RESULTS: Among 2,957,323 children with COVID-19, 206 pediatric SOT recipients (SOTRs) were identified and included in the analysis along with 803 matched non-SOT children. Most infections (96.6%) occurred during the Omicron period; no cases of mortality were reported. Pediatric SOTR had a 3.6-fold (95% confidence interval = 1.1-11.7, P = 0.03) higher risk of severe I, and a 4.9-fold (95% confidence interval = 1.6-15.0, P = 0.006) higher risk of severe III than non-SOT children. No cases of severe II occurred in the non-SOT children. Although not statistically significant, no severe COVID-19 cases were reported in the vaccinated SOT group (0.0% vs 5.7%, P = 0.09 in severe III). CONCLUSION: Pediatric SOTRs have a significantly higher risk of severe COVID-19 than non-SOT children. Our findings support the need for tailored strategies for these high-risk children.

Stepwise Expansion of Antimicrobial Stewardship Programs and Its Impact on Antibiotic Use and Resistance Rates at a Tertiary Care Hospital in Korea.

To optimize antibiotic use, the US CDC has outlined core elements of antimicrobial stewardship programs (ASP). However, they are difficult to implement in limited-resource settings. We report on the successful implementation of a series of ASP with insufficient number of infectious diseases specialists. We retrospectively collected data regarding antibiotic administration and culture results of all patients admitted to a tertiary care teaching hospital, Seoul National University Bundang Hospital (SNUBH), from January 2010 to December 2019. Trends of antibiotic use and antibiotic resistance rates were compared with those from Korean national data. Trend analyses were performed using nonparametric, two-sided, correlated seasonal Mann-Kendall tests. Total antibiotic agent usage has significantly decreased with ASP implementation at SNUBH since 2010. National claim data from tertiary care hospitals have revealed an increase in the use of all broad-spectrum antibiotics except for third-generation cephalosporins (3GC). In contrast, at SNUBH, glycopeptide and fluoroquinolone use gradually decreased, and 3GC and carbapenem use did not significantly change. Furthermore, the rate of colonization with methicillin-resistant Staphylococcus aureus showed a consistently decreasing trend, while that with 3GC- and fluoroquinolone-resistant Escherichia coli significantly increased. Unlike the national rate, the rate of colonization with antibiotic resistant-Klebsiella pneumoniae did not increase and that of 3GC- and fluoroquinolone-resistant Pseudomonas aeruginosa significantly decreased. Stepwise implementation of core ASP elements was effective in reducing antibiotic use despite a lack of sufficient manpower. Long-term multidisciplinary teamwork is necessary for successful and sustainable ASP implementation. IMPORTANCE Antimicrobial stewardship programs aimed to optimize antibiotic use are difficult to implement in limited-resource settings. Our study indicates that stepwise implementation of core antimicrobial stewardship program elements was effective in reducing antibiotic use in a tertiary care hospital despite the lack of sufficient manpower.

Subsequent pregnancy and long-term safety after breast cancer: a retrospective analysis of Korean health insurance data.

PURPOSE: Long-term safety of pregnancy after breast cancer (BC) remains controversial, especially with respect to BC biological subtypes. METHODS: We analyzed a population-based retrospective cohort with BC from 2002 to 2017. Patient-level 1:1 matching was performed between pregnant and nonpregnant women. The study population was categorized into 6 biological subtypes based on the combination of prescribed therapies. Subanalyses were performed considering the time to pregnancy after BC diagnosis, systemic therapy, and pregnancy outcomes. RESULTS: We identified 544 matched women with BC, who were assigned to the pregnant (cases, n = 272) or nonpregnant group (controls, n = 272) of similar characteristics, adjusted for guaranteed bias. These patients were followed up for 10 years, or disease and mortality occurrence after the diagnosis of BC. Survival estimates were calculated. The actuarial 10-year overall survival (OS) rates were 97.4% and 91.9% for pregnant and nonpregnant patients, respectively. The pregnant group showed significantly better OS (adjusted hazard ratio [aHR], 0.29; 95% confidence interval [CI], 0.12-0.68; P = 0.005) and did not have a significantly inferior disease-free survival (aHR, 1.10; 95% CI, 0.61-1.99; P = 0.760). CONCLUSION: Consistent outcomes were observed in every subgroup analysis. Our observational data provides reassuring evidence on the long-term safety of pregnancy in young patients with BC regardless of the BC biological subtype.

Association between haemorrhagic fever with renal syndrome and cancers.

OBJECTIVES: To investigate the risk of haematologic and solid organ malignancies in patients with haemorrhagic fever with renal syndrome (HFRS) compared with the general population. METHODS: This propensity-score-matched cohort study was conducted using data collected from the Korean national health insurance service (NHIS) between January 2003 and December 2017. The HFRS cohort included 5888 newly diagnosed cases of HFRS, and 412,804 general participants from the NHIS database were included as the control cohort. The incidence rate of malignancies was assessed and compared between the HFRS and control cohorts. RESULTS: There were 64 cases of haematologic malignancy in 236,286 person-years of observation, and 1245 cases of solid organ cancer in 209,333 person-years. The risks of haematologic malignancy and solid organ cancer were significantly higher in the HFRS cohort [adjusted hazards ratio (aHR) 4.10, 95% confidence interval (CI) 2.36-7.14] than the control cohort [aHR 2.97, 95% CI 2.60-3.38). In subgroup analysis, the HFRS cohort was associated with high hazard ratios for leukaemia and non-Hodgkin lymphoma. The HFRS cohort also had increased aHRs for all types of solid organ cancer. CONCLUSIONS: Patients with HFRS are at increased risk of both haematologic and solid organ malignancies compared with the general population, and this increased proportionally over time. Careful monitoring for malignancy after the onset of HFRS may be necessary.

Humidifier Disinfectant Consumption and Humidifier Disinfectant-Associated Lung Injury in South Korea: A Nationwide Population-Based Study.

Humidifier disinfectant (HD) is a household biocidal product used in humidifier water tanks to prevent the growth of microorganisms. In 2011, a series of lung injury cases of unknown causes emerged in children and pregnant women who had used HD in Korea. This study investigated changes in the nationwide number of cases of humidifier disinfectant-associated lung injury (HDLI) in concordance with nationwide HD consumption using data covering the entire Korean population. More than 25 kinds of HD products were sold between 1994 and 2011. The number of diagnosed HDLI, assessed by S27.3 (other injuries of lungs) of the Korea National Health Insurance Service (NHIS) data, sharply increased by 2005, subsequently decreased after 2005, and almost disappeared after 2011 in concordance with the annual number of HD sales. The number of self-reported HDLIs, assessed using data from all suspected HDLI cases registered in the Korea Ministry of Environment, changed with the annual number of HD sales, with a delay pattern, potentially induced by the late awareness of lung injury diseases. The present study suggests that changes in the nationwide annual consumption of HD products were consistent with changes in the annual number of HDLI cases in Korea.

Overweight and Obesity are Risk Factors for Coronavirus Disease 2019: A Propensity Score-Matched Case-Control Study.

Although obesity is a risk factor for infection, whether it has the same effect on coronavirus disease 2019 (COVID-19) need confirming. We conducted a retrospective propensity score matched case-control study to examine the association between obesity and COVID-19. This study included data from the Nationwide COVID-19 Registry and the Biennial Health Checkup database, until May 30, 2020. We identified 2,231 patients with confirmed COVID-19 and 10-fold-matched negative test controls. Overweight (body mass index [BMI] 23 to 24.9 kg/m2; adjusted odds ratio [aOR], 1.16; 95% confidence interval [CI], 1.1.03 to 1.30) and class 1 obesity (BMI 25 to 29.9 kg/m2; aOR, 1.27; 95% CI, 1.14 to 1.42) had significantly increased COVID-19 risk, while classes 2 and 3 obesity (BMI ≥30 kg/m2) showed similar but non-significant trend. Females and those <50 years had more robust association pattern. Overweight and obesity are possible risk factors of COVID-19.

Association of prescribed medications with the risk of COVID-19 infection and severity among adults in South Korea.

OBJECTIVES: Concerns have been expressed that some drugs may increase susceptibility to SARS-CoV-2 infection. In contrast, other drugs have generated interest as potential therapeutic agents. METHODS: All adults aged ≥18 years who were tested for COVID-19 were included. Exposure was defined as a prescription of study drugs which would have been continued until 7 days prior to test for COVID-19 or later. The outcome measures were the diagnosis of COVID-19 and severe COVID-19. Disease risk score matching and multiple logistic regression was used. RESULTS: Matched claims and testing results were available for 219,961 subjects, of whom 7,341 (3.34%) were diagnosed with COVID-19. Patients were matched to 36,705 controls, and the subset of 878 patients of severe COVID-19 also matched with 1,927 mild-to-moderate patients. Angiotensin receptor blockers were not associated with either the diagnosis of COVID-19 (adjusted OR [aOR], 1.02; 95% confidence interval [CI], 0.90-1.15) or severe disease (aOR, 1.11; 95% CI, 0.87-1.42). The use of hydroxychloroquine was not associated with a lower risk for COVID-19 (aOR, 0.94; 95% CI, 0.53-1.66) or severe disease (aOR, 3.51; 95% CI, 0.76-16.22). CONCLUSIONS: In this national claims data-based case-control study, no commonly prescribed medications were associated with risk of COVID-19 infection or COVID-19 severity.

Comparison of antiviral effect for mild-to-moderate COVID-19 cases between lopinavir/ritonavir versus hydroxychloroquine: A nationwide propensity score-matched cohort study.

OBJECTIVES: We aimed to compare the antiviral effect of hydroxychloroquine (HCQ) and lopinavir/ritonavir (LPV/r) in patients with COVID-19. METHODS: Nationwide retrospective case-control study was conducted to compare the effect of HCQ and LPV/r on viral shedding duration among patients with mild-to-moderate COVID-19 using the reimbursement data of National Health Insurance Service. After propensity score matching (PSM), multivariate analysis was conducted to determine statistically significant risk factors associated with prolonged viral shedding. RESULTS: Overall, 4197 patients with mild-to-moderate COVID-19 were included. Patients were categorized into three groups: LPV/r (n = 1268), HCQ (n = 801), and standard care without HCQ or LPV/r (controls, n = 2128). The median viral shedding duration was 23 (IQR 17-32), 23 (IQR 16-32), and 18 (IQR 12-25) days in the LPV/r, HCQ, and control groups, respectively. Even after PSM, the viral shedding duration was not significantly different between LPV/r and HCQ groups: 23 (IQR, 17-32) days versus 23 (IQR, 16-32) days. On multivariate analysis, old age, malignancy, steroid use, and concomitant pneumonia were statistically significant risk factors for prolonged viral shedding. CONCLUSION: The viral shedding duration was similar between HCQ and LPV/r treatment groups. There was no benefit in improving viral clearance compared to the control group.

Impact of obesity, fasting plasma glucose level, blood pressure, and renal function on the severity of COVID-19: A matter of sexual dimorphism?

AIMS: This study aimed to assess whether body mass index (BMI), fasting plasma glucose (FPG) levels, blood pressure (BP), and kidney function were associated with the risk of severe disease or death in patients with COVID-19. METHODS: Data on candidate risk factors were extracted from patients' last checkup records. Propensity score-matched cohorts were constructed, and logistic regression models were used to adjust for age, sex, and comorbidities. The primary outcome was death or severe COVID-19, defined as requiring supplementary oxygen or higher ventilatory support. RESULTS: Among 7,649 patients with confirmed COVID-19, 2,231 (29.2%) received checkups and severe COVID-19 occurred in 307 patients (13.8%). A BMI of 25.0-29.9 was associated with the outcome among women (aOR, 2.29; 95% CI, 1.41-3.73) and patients aged 50-69 years (aOR, 1.64; 95% CI, 1.06-2.54). An FPG ≥ 126 mg/dL was associated with poor outcomes in women (aOR, 2.06; 95% CI, 1.13-3.77) but not in men. Similarly, estimated glomerular filtration rate (eGFR) < 60 ml/min/1.73 m2 was a risk factor in women (aOR, 3.46; 95% CI, 1.71-7.01) and patients aged < 70 years. CONCLUSIONS: The effects of BMI, FPG, and eGFR on outcomes associated with COVID-19 were prominent in women but not in men.

Effect of Underlying Comorbidities on the Infection and Severity of COVID-19 in Korea: a Nationwide Case-Control Study.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic is an emerging threat worldwide. It remains unclear how comorbidities affect the risk of infection and severity of COVID-19. METHODS: This is a nationwide retrospective case-control study of 219,961 individuals, aged 18 years or older, whose medical costs for COVID-19 testing were claimed until May 15, 2020. COVID-19 diagnosis and infection severity were identified from reimbursement data using diagnosis codes and on the basis of respiratory support use, respectively. Odds ratios (ORs) were estimated using multiple logistic regression, after adjusting for age, sex, region, healthcare utilization, and insurance status. RESULTS: The COVID-19 group (7,341 of 219,961) was young and had a high proportion of female. Overall, 13.0% (954 of 7,341) of the cases were severe. The severe COVID-19 group had older patients and a proportion of male ratio than did the non-severe group. Diabetes (odds ratio range [ORR], 1.206-1.254), osteoporosis (ORR, 1.128-1.157), rheumatoid arthritis (ORR, 1.207-1.244), substance use (ORR, 1.321-1.381), and schizophrenia (ORR, 1.614-1.721) showed significant association with COVID-19. In terms of severity, diabetes (OR, 1.247; 95% confidential interval, 1.009-1.543), hypertension (ORR, 1.245-1.317), chronic lower respiratory disease (ORR, 1.216-1.233), chronic renal failure, and end-stage renal disease (ORR, 2.052-2.178) were associated with severe COVID-19. CONCLUSION: We identified several comorbidities associated with COVID-19. Health care workers should be more careful while diagnosing and treating COVID-19 when patients have the abovementioned comorbidities.

Statins and All-Cause Mortality in Patients Undergoing Hemodialysis.

Background Recommendations have not yet been established for statin therapy in patients on maintenance dialysis. In this study, we aimed to evaluate the effects of statin therapy on all-cause mortality in patients undergoing maintenance hemodialysis. Methods and Results This retrospective cohort study analyzed data from adults, aged ≥30 years, who were on maintenance hemodialysis for end-stage renal disease. Data on statin use, along with other clinical information between 2007 and 2017, were extracted from the Health Insurance Review and Assessment Service database in Korea. In total, 65 404 patients were included, and 41 549 (73.2%) patients had received statin therapy for a mean duration of 3.6±2.6 years. Compared with statin nonusers before and after the initiation of hemodialysis (entry), patients who initiated statin therapy after entry and patients who continued statins from the pre-end-stage renal disease to post-end-stage renal disease period had a lower risk of all-cause mortality; the adjusted hazard ratios (95% CIs) were 0.48 (0.47-0.50; P<0.001) for post-end-stage renal disease only statin users and 0.59 (0.57-0.60; P<0.001) for continuous statin users. However, those discontinuing statins before or at entry showed a higher risk of all-cause mortality. Statin-ezetimibe combinations were associated with better survival benefits than fixed patterns of statin therapy. These results were consistent across various subgroups, including elderly patients aged >75 years, and were maintained even after propensity score matching. Conclusions Our results showed that in adult patients undergoing maintenance hemodialysis, statin therapy, preferably combined with ezetimibe, was associated with a lower risk of all-cause mortality.

Oseltamivir and the Risk of Neuropsychiatric Events: A National, Population-based Study.

BACKGROUND: Reports of serious neuropsychiatric events (NPEs), specifically suicide/suicide attempts, following the use of oseltamivir have led to public concerns. Our aim in this study was to determine whether an association exists between oseltamivir use and NPEs. METHOD: This study was a population-based, retrospective, cohort study on a random sample of 50% of individuals in the Korean National Health Insurance Service (KNIS) database aged ≥8 years who were diagnosed with influenza between 2009 and 2017. The primary exposure was oseltamivir prescription at the time of influenza diagnosis, whereas the primary outcome was a diagnosis of an NPE within 30 days after the influenza diagnosis. Information on oseltamivir prescription, diagnoses of NPEs, demographic characteristics, comorbidities, drugs prescribed within the year before influenza diagnosis, and healthcare utilization were extracted from the KNIS database. RESULTS: Of 3 352 015 individuals included in the analysis, 1 266 780 (37.8%) were prescribed oseltamivir. The incidence of NPEs was 0.86% and 1.16% in patients who were and were not prescribed oseltamivir, respectively (hazard ratio [HR], 0.74; 95% confidence interval [CI], .73 to .75; P < .001). Oseltamivir use was not associated with a difference in the overall risk of NPEs in the adjusted model (HR, 0.98; 95% CI, .96 to 1.01; P = .16), but the incidence of moderate-to-severe NPEs was significantly lower in those prescribed oseltamivir (HR, 0.92; 95% CI, .88-.96; P < .001). CONCLUSION: Treating influenza with oseltamivir does not increase the risk of NPEs. Thus, public concern regarding its use is unwarranted.

Factors associated with organized and opportunistic cancer screening: Results of the Korea National Health and Nutrition Examination Survey (KNHANES) 2007-2011.

BACKGROUND: Cancer is one of the leading causes of death in Korea. To reduce cancer incidence, the Korean National Cancer Center (KNCC) has been expanding its organized cancer screening program. In addition, there are opportunistic screening programs that can be chosen by individuals or their healthcare providers. The purpose of this study was to investigate factors associated with participation in organized and opportunistic cancer screening programs, with a particular focus on socioeconomic factors. MATERIALS AND METHODS: We used data from the Korea National Health and Nutrition Examination Survey (KNHANES), a cross-sectional nationwide study conducted by the Korean Ministry of Health and Welfare from 2007 to 2011. The study included information from 9,708 men and 12,739 women aged 19 years or over. Multinomial logistic regression analysis was conducted, adjusting for age, year of data collection, residential region, current smoking status, current alcohol consumption status, exercise, marriage status, job status, perceived health status, stress level, BMI, limitation of activities, cancer history, health insurance type, and private insurance status, to investigate the association between education level, economic status, and cancer screening participation. RESULTS: In terms of education level, disparities in attendance were observed only for the opportunistic screening program. In contrast, there was no association between education level and participation in organized screening. In terms of economic status, disparities in opportunistic screening participation were observed at all income levels, but disparities in organized screening participation were observed only at the highest income level. CONCLUSIONS: Our findings reveal that socioeconomic factors, including educational level and economic status, were not significantly associated with participation in organized cancer screening, except at the highest level of income.

The gender-specific association between age at first drink and later alcohol drinking patterns in Korea.

This study investigated the association between the age at first drink and later alcohol drinking patterns, and analyzed whether differences in the association exist among Korean adults according to gender. The subjects included 10,649 adults (5,405 men and 5,244 women) from the fourth Korean National Health and Nutrition Examination Survey between 2007 and 2009, which extracted the standard survey household by using the proportional systematic sampling method. Baseline individual characteristics, the age at first drink, and individual alcohol drinking patterns were obtained by specially trained interviewers or examiners. The association between the age at first drink and the adult alcohol drinking patterns was summarized with odds ratios and their confidence intervals obtained from multiple logistic regression analysis with sampling weights of KNHANES complex sample survey design. The results of this study show that age, co-habitation, occupation, smoking, and self-rated stress level were significantly related to the drinking patterns for men, whereas education, co-habitation, smoking, and self-rated stress level were significant factors for the drinking patterns of women. The association between the age at first drink and the adult alcohol consumption was significant for both genders and, interestingly, the alcohol drinking patterns were significantly differed by gender even after controlling for the individual characteristics. These results imply a need for gender-specific strategies to prevent hazardous alcohol consumption at a later time for Korean.

Tracking variations in fluorescent-dissolved organic matter in an aerobic submerged membrane bioreactor using excitation-emission matrix spectra combined with parallel factor analysis.

In this study, the variations in the fluorescent components of dissolved organic matter (DOM) were tracked for an aerobic submerged membrane bioreactor (MBR) at three different operation stages (cake layer formation, condensation, and after cleaning). The fluorescent DOM was characterized using excitation-emission matrix (EEM) spectroscopy combined with parallel factor analysis (PARAFAC). Non-aromatic carbon structures appear to be actively involved in the membrane fouling for the cake layer formation stage as revealed by much higher UV-absorbing DOM per organic carbon found in the effluent versus those inside the reactor. Four fluorescent components were successfully identified from the reactor and the effluent DOMs by EEM-PARAFAC modeling. Among those in the reactor, microbial humic-like fluorescence was the most abundant component at the cake layer formation stage and tryptophan-like fluorescence at the condensation stage. In contrast to the reactor, relatively similar composition of the PARAFAC components was exhibited for the effluent at all three stages. Tryptophan-like fluorescence displayed the largest difference between the reactor and the effluent, suggesting that this component could be a good tracer for membrane fouling. It appears that the fluorescent DOM was involved in membrane fouling by cake layer formation rather than by internal pore adsorption because its difference between the reactor and the effluent was the highest among all the four components, even after the membrane cleaning. Our study provided an insight into the fate and the behavior fluorescent DOM components for an MBR system, which could be an indicator of the membrane fouling.