Korea Nurses' Health Study and the health of reproductive-aged women: a cohort profile.

The Korea Nurses' Health Study (KNHS) is an ongoing, large-scale, prospective cohort study of female nurses, focusing on the effects of occupational, environmental, and lifestyle factors on the health of women. The first KNHS survey was performed in 2013-2014 (n=20,613). As of December 2023, 11 follow-up surveys have been conducted. Participants who were pregnant were asked to participate in the early pregnancy survey (n=2,179) and postpartum survey after giving birth (n=2,790). The main variables included sociodemographic, work-related, lifestyle, physical, mental, and women's health factors. Blood, urine, and toenail samples were collected from a participant subgroup of the first survey (n=1,983). The subgroups of the second survey completed a food frequency questionnaire in 2019 (n=300) and 2021 (n=871). In 2020, a subgroup of the first survey answered a coronavirus disease 2019 (COVID-19)-related survey (n=975). To examine various health-related factors in young adults, new participants were added to the KNHS cohort in the 11th (n=1,000) and 12th (n=1,002) surveys. The KNHS cohort will help identify health and illness determinants in Korean women. Data can be accessed at https://coda.nih.go.kr/frt/index.do.

Digital Health Technology Use Among Older Adults: Exploring the Impact of Frailty on Utilization, Purpose, and Satisfaction in Korea.

BACKGROUND: The importance of digital technology is increasing among older adults. In this study, the digital health technology utilization status, purpose, and satisfaction of older adults were investigated according to frailty. METHODS: A face-to-face survey was conducted among adults aged 65 years or older. Frailty was defined using the Korean version of the fatigue, resistance, ambulation, illnesses, and loss of weight scale. RESULTS: A total of 505 participants completed the survey, with 153 (30.3%) identified as pre-frail or frail and 352 (69.7%) as healthy. All respondents used smartphones; 440 (87.1%) were application users, and 290 (57.4%) were healthcare application users. Wearable devices were used by only 36 patients (7.1%). Pre-frail or frail respondents used social media more frequently than healthy respondents (19.4% vs. 7.4%, P < 0.001). Among the respondents, 319 (63.2%) were not able to install or delete the application themselves, and 277 (54.9%) stated that the application was recommended by their children (or partner). Pre-frail and frail respondents used more healthcare applications to obtain health information (P = 0.002) and were less satisfied with wearable devices (P = 0.02). CONCLUSION: The usage rate of digital devices, including mobile phones among older adults in Korea is high, whereas that of wearable devices is low. There was a notable difference in the services used by pre-frail and frail respondents compared to healthy respondents. Therefore, when developing digital devices for pre-frail and frail older adults, it is crucial to incorporate customized services that meet their unique needs, particularly those services that they frequently use.

Group I pharmaceuticals of IARC and associated cancer risks: systematic review and meta-analysis.

We aimed to summarize the cancer risk among patients with indication of group I pharmaceuticals as stated in monographs presented by the International Agency for Research on Cancer working groups. Following the PRISMA guidelines, a comprehensive literature search was conducted using the PubMed database. Pharmaceuticals with few studies on cancer risk were identified in systematic reviews; those with two or more studies were subjected to meta-analysis. For the meta-analysis, a random-effects model was used to calculate the summary relative risks (SRRs) and 95% confidence intervals (95% CIs). Heterogeneity across studies was presented using the Higgins I square value from Cochran's Q test. Among the 12 group I pharmaceuticals selected, three involved a single study [etoposide, thiotepa, and mustargen + oncovin + procarbazine + prednisone (MOPP)], seven had two or more studies [busulfan, cyclosporine, azathioprine, cyclophosphamide, methoxsalen + ultraviolet (UV) radiation therapy, melphalan, and chlorambucil], and two did not have any studies [etoposide + bleomycin + cisplatin and treosulfan]. Cyclosporine and azathioprine reported increased skin cancer risk (SRR = 1.32, 95% CI 1.07-1.62; SRR = 1.56, 95% CI 1.25-1.93) compared to non-use. Cyclophosphamide increased bladder and hematologic cancer risk (SRR = 2.87, 95% CI 1.32-6.23; SRR = 2.43, 95% CI 1.65-3.58). Busulfan increased hematologic cancer risk (SRR = 6.71, 95% CI 2.49-18.08); melphalan was associated with hematologic cancer (SRR = 4.43, 95% CI 1.30-15.15). In the systematic review, methoxsalen + UV and MOPP were associated with an increased risk of skin and lung cancer, respectively. Our results can enhance persistent surveillance of group I pharmaceutical use, establish novel clinical strategies for patients with indications, and provide evidence for re-categorizing current group I pharmaceuticals into other groups.

Risk Factors of Gastric Cancer and Lifestyle Modification for Prevention.

Gastric cancer has been consistently decreasing worldwide, whereas cardia gastric cancer is on the rise. This indicates that the exposure rates to epidemiological causes are changing. In this study, we aim to review the risk factors for gastric cancer with respect to cardia and non-cardia types. One of the most significant risk factors for gastric cancer is Helicobacter pylori infection. H. pylori infection is known as a risk factor for non-cardia gastric cancer, and there have been results indicating that H. pylori infection is not associated with cardia gastric cancer. However, in the East Asian region, there is epidemiological evidence suggesting that H. pylori infection might be a risk factor for cardia gastric cancer. Smoking and alcohol consumption are known risk factors for gastric cancer, regardless of anatomical location. Obesity is considered a factor in the development of cardia gastric cancer. However, further research is needed to understand the specific relationship with non-cardia gastric cancer. The consumption of high-salt and processed meat is more distinctly associated with non-cardia gastric cancer than in cardia gastric cancer. In addition to these factors, exposure to chemicals and radiation are considered risk factors for gastric cancer. Primary prevention of gastric cancer involves eliminating or avoiding risk factors such as H. pylori eradication and adopting a healthy lifestyle, including quitting smoking, reducing alcohol consumption, maintaining a healthy weight, and having a low-salt diet.

Projection of Cancer Incidence and Mortality From 2020 to 2035 in the Korean Population Aged 20 Years and Older.

OBJECTIVES: This study aimed to identify the current patterns of cancer incidence and estimate the projected cancer incidence and mortality between 2020 and 2035 in Korea. METHODS: Data on cancer incidence cases were extracted from the Korean Statistical Information Service from 2000 to 2017, and data on cancer-related deaths were extracted from the National Cancer Center from 2000 to 2018. Cancer cases and deaths were classified according to the International Classification of Diseases, 10th edition. For the current patterns of cancer incidence, age-standardized incidence rates (ASIRs) and age-standardized mortality rates were investigated using the 2000 mid-year estimated population aged over 20 years and older. A joinpoint regression model was used to determine the 2020 to 2035 trends in cancer. RESULTS: Overall, cancer cases were predicted to increase from 265 299 in 2020 to 474 085 in 2035 (growth rate: 1.8%). The greatest increase in the ASIR was projected for prostate cancer among male (7.84 vs. 189.53 per 100 000 people) and breast cancer among female (34.17 vs. 238.45 per 100 000 people) from 2000 to 2035. Overall cancer deaths were projected to increase from 81 717 in 2020 to 95 845 in 2035 (average annual growth rate: 1.2%). Although most cancer mortality rates were projected to decrease, those of breast, pancreatic, and ovarian cancer among female were projected to increase until 2035. CONCLUSIONS: These up-to-date projections of cancer incidence and mortality in the Korean population may be a significant resource for implementing cancer-related regulations or developing cancer treatments.

The Korea Cohort Consortium: The Future of Pooling Cohort Studies.

OBJECTIVES: We introduced the cohort studies included in the Korea Cohort Consortium (KCC), focusing on large-scale cohort studies established in Korea with a prolonged follow-up period. Moreover, we also provided projections of the follow-up and estimates of the sample size that would be necessary for big-data analyses based on pooling established cohort studies, including population-based genomic studies. METHODS: We mainly focused on the characteristics of individual cohort studies from the KCC. We developed "PROFAN", a Shiny application for projecting the follow-up period to achieve a certain number of cases when pooling established cohort studies. As examples, we projected the follow-up periods for 5000 cases of gastric cancer, 2500 cases of prostate and breast cancer, and 500 cases of non-Hodgkin lymphoma. The sample sizes for sequencing-based analyses based on a 1:1 case-control study were also calculated. RESULTS: The KCC consisted of 8 individual cohort studies, of which 3 were community-based and 5 were health screening-based cohorts. The population-based cohort studies were mainly organized by Korean government agencies and research institutes. The projected follow-up period was at least 10 years to achieve 5000 cases based on a cohort of 0.5 million participants. The mean of the minimum to maximum sample sizes for performing sequencing analyses was 5917-72 102. CONCLUSIONS: We propose an approach to establish a large-scale consortium based on the standardization and harmonization of existing cohort studies to obtain adequate statistical power with a sufficient sample size to analyze high-risk groups or rare cancer subtypes.

Association between Body Mass Index and Risk of Gastric Cancer by Anatomic and Histologic Subtypes in Over 500,000 East and Southeast Asian Cohort Participants.

BACKGROUND: This study was performed to investigate the association between body mass index (BMI) and gastric cancer in East and Southeast Asia where most of gastric cancer is non-cardia gastric cancer. METHODS: On the basis of 8,997 gastric cancer cases among the Asia Cohort Consortium participants from China, Japan, Korea, and Singapore (N = 538,835), we assessed gastric cancer risk according to BMI by calculating hazard ratios (HR) and 95% confidence intervals (CI) using the Cox proportional hazard regression model. RESULTS: A U-shaped associations between BMI and gastric cancer risk were observed. Gastric cancer risks in underweight group (<18.5 kg/m2) and in obesity group (≥27.5 kg/m2) were higher than reference BMI group (23-24.9 kg/m2; HR, 1.15; 95% CI, 1.05-1.25 for underweight; HR, 1.12; 95% CI, 1.03-1.22 for obesity, respectively). The associations of underweight and obesity with gastric cancer risk were consistent in the analyses for non-cardia gastric cancer, intestinal-type gastric cancer, and late-onset gastric cancer. No significant association of underweight and obesity with the risk of cardia gastric cancer, diffuse-type gastric cancer, and early-onset gastric cancer was observed. In addition, we found that the U-shaped association between BMI and gastric cancer risk remained in nonsmokers, while only underweight was related to increased gastric cancer risk in smokers. CONCLUSIONS: BMI has a U-shaped association with gastric cancer risk in East and Southeast Asian population, especially for the non-cardia gastric cancer, intestinal-type gastric cancer, and late-onset gastric cancer. IMPACT: Future studies with consideration of anatomic location and histology of gastric cancer are needed to establish the association of underweight as well as obesity with gastric cancer risk.

Apnea-hypopnea Index is Correlated with Pulse Rate in Patients with Sleep-related Breathing Disorder without Hypertension, Cardiovascular Disease, or Diabetes Mellitus.

Objective: This study aimed to compare the mean pulse rate (PR) and mean blood pressure (BP) between patients with obstructive sleep apnea (OSA) and those with simple snoring (SS) during a 24-hour period, and to investigate the correlation between apnea-hypopnea index (AHI), PR, and BP in sleep-related breathing disorder (SRBD) patients with and without hypertension, diabetes mellitus (DM), and cardiovascular diseases (CVDs). Methods: Ninety SRBD patients underwent full-night polysomnography, and ambulatory BP and PR were monitored for 24 hours. Participants were classified into OSA (AHI ≥ 5) and control (SS) (AHI < 5) groups, and BP and PR were compared. Participants were also divided into groups with and without hypertension, CVDs, or DM to analyze the correlation between AHI, BP, and PR in each group. Results: Mean PRs during the daytime period and during the whole 24-hour period in the OSA group were significantly higher than those in the SS group after controlling for potential confounders. No significant difference was observed in mean BP between the groups. Partial correlation analysis after controlling for confounders showed significant correlation between AHI and PR during daytime and the 24-hour period in participants without hypertension, DM, or CVDs, but not in participants with these conditions. Conclusion: The significant differences and correlations only in PR (not in BP) found in this study suggest that PR could be an early marker for SRBD in individuals without comorbidities, and that an increased sympathetic tone could be responsible for future occurrence of CVD.

Efficacy and safety of rapid intermittent bolus compared with slow continuous infusion in patients with severe hypernatremia (SALSA II trial): a study protocol for a randomized controlled trial.

BACKGROUND: Hypernatremia is a common electrolyte disorder in children and elderly people and has high short-term mortality. However, no high-quality studies have examined the correction rate of hypernatremia and the amount of fluid required for correction. Therefore, in this study, we will compare the efficacy and safety of rapid intermittent bolus (RIB) and slow continuous infusion (SCI) of electrolyte-free solution in hypernatremia treatment. METHODS: This is a prospective, investigator-initiated, multicenter, open-label, randomized controlled study with two experimental groups. A total of 166 participants with severe hypernatremia will be enrolled and divided into two randomized groups; both the RIB and SCI groups will be managed with electrolyte-free water. We plan to infuse the same amount of fluid to both groups, for 1 hour in the RIB group and continuously in the SCI group. The primary outcome is a rapid decrease in serum sodium levels within 24 hours. The secondary outcomes will further compare the efficacy and safety of the two treatment protocols. CONCLUSION: This is the first randomized controlled trial to evaluate the efficacy and safety of RIB correction compared with SCI in adult patients with severe hypernatremia.

Association Between Subjective-Objective Discrepancy of Sleeping Time and Health-Related Quality of Life: A Community-Based Polysomnographic Study.

OBJECTIVE: This study aimed to investigate the existence of a difference in quality of life (QOL) between individuals with and without significant subjective-objective discrepancy (SOD) in total sleep time (TST). METHODS: From the Sleep Heart Health Study 2, 2540 individuals who had completed polysomnography, a morning sleep survey, and the 36-item Short-Form Health Survey (SF-36) were included in the analyses. The participants were classified as normoestimators (estimation of TST <±60 minutes), underestimators (underestimation of TST ≥60 minutes), or overestimators (overestimation of TST ≥60 minutes). The standardized SF-36 QOL scores were compared among the three groups. An adjusted partial correlation analysis was conducted between SOD and QOL. RESULTS: Of the 2540 participants, 1617 (63.7%), 433 (17.0%), and 490 (19.3%) were assigned to the normoestimator, underestimator, and overestimator groups, respectively. The bodily pain and social functioning components of the SF-36 score were significantly lower in the underestimators than in the normoestimators, whereas the physical functioning component was significantly lower in the overestimators than in the normoestimators. The absolute value of SOD in the TST showed a significant negative correlation with the physical and mental components of the SF-36. CONCLUSIONS: QOL was significantly better in the normoestimator than in the other groups and linearly correlated with the absolute value of SOD. This study suggests that a high prevalence of positive and negative sleep misperception in a community population can be a potential factor associated with poor QOL and potential comorbidities.

Sex and Economic Disparity Related to Reperfusion Therapies for Patients with Acute Ischemic Stroke in South Korea across a 10-Year Period: A Nationwide Population-Based Study Using the National Health Insurance Database.

A complete enumeration study was conducted to evaluate trends related to reperfusion therapies (intravenous thrombolysis (IVT) and endovascular treatment (EVT)) in acute ischemic stroke (AIS) in South Korea, according to sex, economic status, and age, over a 10-year period retrospectively, using the National Health Information Database (NHIS-2020-1-481). This study included AIS patients aged ≥20 years who were hospitalized in a general hospital or tertiary hospital for ≥4 days and underwent brain imaging during the same period. Study participants were classified by sex, economic status (Medical Aid beneficiaries and National Health Insurance beneficiaries) and age (20-44, 45-64, 65-79, and ≥80 years). Women showed a significantly lower OR (Odds ratio) than men in IVT (OR: 0.75; 95% CI: 0.73-0.77), EVT (OR: 0.96; 95% CI: 0.93-0.99), and any therapy (OR: 0.82; 95% CI: 0.80-0.84). The Medical Aid beneficiaries showed significantly lower OR in IVT (OR 0.91, 95% CI 0.88-0.95), EVT (OR 0.93, 95% CI 0.89-0.98), and either therapy (OR 0.92, 95% CI 0.90-0.95) than the National Health Insurance beneficiaries. This study showed sex and economic disparity related to reperfusion therapies in patients with AIS in Korea.

Association of coffee drinking with all-cause and cause-specific mortality in over 190,000 individuals: data from two prospective studies.

We examined the association of coffee drinking with all-cause and cause-specific mortality in a pooled analysis of two Korean prospective cohort studies: The Korea National Health and Nutrition Examination Survey and the Korean Genome and Epidemiology Study. We included 192,222 participants, and a total of 6057 deaths were documented. Cox proportional hazards model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs), and the HRs were combined using a random-effects model. Coffee drinking was associated with a lower risk of all-cause mortality [HR (95% CI) = 0.84 (0.77-0.92), for ≥3 cups/day of coffee drinking versus non-drinkers; p for trend = 0.004]. We observed the potential benefit of coffee drinking for mortality due to cardiovascular disease, respiratory disease, and diabetes, but not for cancer mortality. Overall, we found that moderate coffee drinking was associated with a lower risk of death in population-based cohort analysis of Korean adults.

Indoor Tanning and the Risk of Overall and Early-Onset Melanoma and Non-Melanoma Skin Cancer: Systematic Review and Meta-Analysis.

The aim of this study was to examine the association between indoor tanning use and the risk of overall and early-onset (age < 50) melanoma and non-melanoma skin cancer (NMSC). To evaluate the association between indoor tanning and skin cancer, a systematic review of the literature published until July 2021 was performed using PubMed, EMBASE, and MEDLINE. Summary relative risk (RR) from 18 studies with 10,406 NMSC cases and 36 studies with 14,583 melanoma cases showed significant association between skin cancer and indoor tanning (melanoma, RR= 1.27, 95% CI 1.16-1.39; NMSC, RR = 1.40, 95% CI 1.18-1.65; squamous cell carcinoma (SCC), RR = 1.58, 95% CI 1.38-1.81; basal cell carcinoma (BCC), RR = 1.24, 95% CI 1.00-1.55). The risk was more pronounced in early-onset skin cancer (melanoma, RR = 1.75, 95% CI 1.14-2.69; NMSC, RR = 1.99, 95% CI 1.48-2.68; SCC, RR = 1.81, 95% CI 1.38-2.37; BCC, RR = 1.75, 95% CI 1.15-2.77). Moreover, first exposure at an early age (age ≤ 20 years) and higher exposure (annual frequency ≥ 10 times) to indoor tanning showed increasing risk for melanoma (RR = 1.47, 95% CI 1.16-1.85; RR = 1.52, 1.22-1.89) and NMSC (RR = 2.02, 95% CI 1.44-2.83; RR = 1.56, 95% CI 1.31-1.86). These findings provide evidence supporting primary prevention policies regulating modifiable behaviors to reduce the additional risk of skin cancer among younger adults.

The Association between Plasma Concentration of Phytoestrogens and Hypertension within the Korean Multicenter Cancer Cohort.

In order to examine the association between plasma phytoestrogen concentration (genistein, daidzein, equol and enterolactone) and hypertension, we conducted a nested case-control study for 229 hypertension cases including 112 prehypertension and 159 healthy controls derived from the Korean Multi-center Cancer Cohort (KMCC). The concentration of plasma phytoestrogens was measured using time-resolved fluoroimmunoassay. We assessed the association between plasma phytoestrogens and hypertension using logistic regression models using odds ratio (OR) and 95% confidence interval (95%CI). The highest tertile of plasma equol and enterolactone concentration exhibited a significantly decreased risk of hypertension (equol, OR = 0.34, 95%CI 0.20-0.57; enterolactone, OR = 0.32, 95%CI 0.18-0.57), compared with the lowest tertile. Equol and enterolactone showed reduced ORs for prehypertension (the highest tertile relative to the lowest tertile, OR = 0.50, 95%CI 0.26-0.96; OR = 0.38, 95%CI 0.19-0.75, respectively) and hypertension (OR = 0.42, 95%CI 0.22-0.81; OR = 0.28, 95%CI 0.14-0.54, respectively). There was a stronger association in hypertension (the highest tertile relative to the lowest tertile in obesity vs. non-obesity; equol, OR = 0.06 vs. 0.63; enterolactone, OR = 0.07 vs. 0.46; both p-heterogeneity < 0.01). This study suggests that equol and enterolactone may contribute to prevent primarily prehypertension and hypertension, and control cardiovascular disease (CVD) based on the continuum of hypertension and CVD. Further study to assess hypertension risk based on useful biomarkers, including phytoestrogens, may contribute to primary prevention of hypertension.

Correlations among anti-Müllerian hormone levels, body mass index and lipid profile in reproductive-aged women: The Korea Nurses' Health Study.

AIM: This study aimed to evaluate the correlations among anti-Müllerian hormone levels, body mass index and lipid profile in female nurses of reproductive age. DESIGN: This is a descriptive cross-sectional study that used data from the Korea Nurses' Health Study, based on Nurses' Health Study 3 in the United States. METHODS: Participants included 448 female nurses of reproductive age. They provided details about their work experience, shift work, body mass index and history of polycystic ovary syndrome. Serum anti-Müllerian hormone levels and lipid profile were measured using blood samples. Statistical analysis included quantile regression analysis using STATA 13.0. Data were collected between November 2016 and March 2017 from Module 5 of the Korean Nurses' Health Study. RESULTS: Approximately 12% of the participants were underweight, and roughly one-tenth were either overweight or obese. Although linear regression showed no relationship between anti-Müllerian hormone levels and body mass index, quantile regression showed that body mass index, total cholesterol levels and low-density lipoprotein levels were negatively correlated with anti-Müllerian hormone levels at the lower tails of the dependent variable. Meanwhile, high-density lipoprotein levels were positively correlated with anti-Müllerian hormone at the higher percentiles of anti-Müllerian hormone levels. CONCLUSION: These findings suggest the possibility that changes in the lipid profile may influence anti-Müllerian hormone levels in women with diminished ovarian function, rather than obesity itself.

Elevated levels of soluble ST2 but not galectin-3 are associated with increased risk of mortality in hemodialysis patients.

BACKGROUND: The soluble forms of suppression of tumorigenicity-2 (ST2) and galectin-3 have been proposed as novel biomarkers for cardiac fibrosis and heart failure, as well as predictors of cardiovascular events and mortality. However, there are limited data on the association between soluble ST2 and galectin-3 and clinical outcomes in patients with kidney failure on replacement therapy. To determine this, we examined the associations between soluble ST2 and galectin-3 and all-cause mortality and cardiovascular events in patients on hemodialysis. METHODS: This study included maintenance hemodialysis patients (over 18 years old) who consented to preserve their serum in the Biobank at our institution between March 2014 and March 2015. We used Cox proportional hazards regression analysis to evaluate the associations between soluble ST2, galectin-3 levels, and clinical outcomes. The primary outcome was all-cause mortality, the secondary outcome was cardiovascular disease, and patients were followed for both outcomes until March 2018. RESULTS: A total of 296 patients were analyzed in this study. The mean age was 57 ± 13 years, and 53.0% were male. Serum concentration of soluble ST2 was significantly associated with higher mortality, after adjustment for confounding factors, but was not associated with cardiovascular disease. Serum galectin-3 level was not independently associated with either outcome after adjustment. CONCLUSION: Elevated soluble ST2 is independently associated with an increased risk of mortality, but not with cardiovascular disease, in patients on hemodialysis. Elevated galectin-3 was not associated with mortality or cardiovascular disease.

The Effect of Korean Red Ginseng on Symptoms and Inflammation in Patients With Allergic Rhinitis.

Korean red ginseng (KRG) has been traditionally used in Korea for health improvement. However, the clinical effect of KRG intake on the symptoms in patients with allergic rhinitis remains unknown. Our study was performed to identify the clinical effects of KRG on patients with allergic rhinitis and to examine the effect of KRG on allergic inflammatory reaction. We evaluated 60 patients with allergic rhinitis. All the patients were treated for 4 weeks. The patients were divided into 3 groups, according to the medication. Twenty patients were treated with KRG, 20 patients with the placebo, and 20 patients with the antihistamine. The patients recorded their symptoms in a daily symptom diary card. The patients checked the peak nasal inspiratory flow rate 2 times a day. Total serum immunoglobulin E (IgE) and serum-specific IgE were measured by ImmunoCap method before and after 4-week medication. The Th2 cytokines interleukin-4 (IL-4), IL-5, and IL-10 were checked in the serum before and after the 4-week treatment. The eosinophil counts in the nasal smears were checked. Korean red ginseng group has shown the significant improvement in rhinorrhea, nasal itching, and eye itching. Both the antihistamine and KRG groups showed a significant decrease in total IgE level at the end of treatment. The serum IL-4 level and eosinophil counts in the nasal smears were significantly decreased both in the antihistamine and in the KRG groups. In conclusion, KRG might be a useful treatment modality for patients with allergic rhinitis.

Risk factors for herpes zoster in patients with rheumatic diseases: a nationwide cohort study in Korea.

OBJECTIVE: To determine the risk factors for herpes zoster (HZ) in patients with rheumatic diseases in Korea. METHODS: We used the nationwide database of the Health Insurance Review & Assessment Service to analyse patients aged ≥20 years who had visited a hospital more than twice for rheumatic disease as a principal diagnosis from January 2009 to April 2013. HZ was identified using HZ-related Korean Standard Classification of Diseases 6 (KCD-6) codes and the prescription of antiviral agents. The relationship between demographics, comorbidities and medications and HZ risk was analysed by Cox proportional hazards models. RESULTS: HZ developed in 1869 patients. In Cox proportional hazards models, female sex but not age showed an increased adjusted hazard ratio (HR) for HZ. Comorbidities such as haematologic malignancies, hypertension, diabetes mellitus, and chronic lung and liver diseases led to an increased HR. HZ risk was higher in patients with SLE (HR: 4.29, 95% CI: 3.49, 5.27) and Behçet's syndrome (BS, HR: 4.54; 95% CI: 3.66, 5.64) than with RA. The use of conventional DMARDs, immunosuppressants, TNF inhibitors, glucocorticoids and NSAIDs increased the HR. Infliximab and glucocorticoids (equivalent prednisolone dose >15 mg/day) produced the highest HZ risk (HR: 2.91, 95% CI: 1.72, 4.89; HR: 2.85, 95% CI: 2.15, 3.77, respectively). CONCLUSION: Female sex, comorbidities and medications increased HZ risk in patients with rheumatic diseases and even young patients could develop HZ. Compared with RA, SLE and BS are stronger HZ risk factors. Patients with rheumatic diseases and these risk factors are potential target populations for HZ vaccination.

Isoflavone intake on the risk of overall breast cancer and molecular subtypes in women at high risk for hereditary breast cancer.

PURPOSE: We investigated the association between isoflavone (ISF) intake and hereditary breast cancer (BC) risk, particularly by molecular subtype, in East-Asian BRCA1/2 mutation carriers and non-carriers at a high risk of hereditary breast cancer (i.e., family history of BC (FHBC) and early-onset BC [EOBC, age < 40 years]). METHODS: The association between ISF intake and BC risk by molecular subtypes was assessed in 1709 participants (407 BRCA1/2 carriers, 585 FHBC non-carriers, 586 EOBC non-carriers, and 131 unaffected non-carriers) from the Korean Hereditary Breast Cancer Study using hazard ratios (HRs) and 95% confidence intervals (CIs) in weighted Cox regression models. Daily ISF intake was assessed using a validated food frequency questionnaire. We evaluated gene-environment interactions between BRCA1/2 mutation and ISF intake in 1604 BC cases by calculating the case-only odds ratios (CORs) and 95% CIs in logistic regression models. RESULTS: ISF intake was inversely associated with luminal A BC risk in BRCA2 mutation carriers and FHBC non-carriers (HR = 0.14, 95% CI = 0.04-0.50 for high intake [ISF intake ≥ 15.50 mg/day]; HR = 0.27, 95% CI = 0.11-0.69 for high intake, respectively). We observed a reduced risk of triple negative BC (TNBC) in BRCA1 carriers and FHBC non-carriers (HR = 0.09, 95% CI = 0.02-0.40 for high intake; HR = 0.19, 95% CI = 0.05-0.69 for high intake, respectively). In the case-only design, an interaction between BRCA1 mutation carrier status and ISF intake emerged in TNBC patients (COR = 0.39, 95% CI = 0.16-0.95). CONCLUSIONS: This study suggests that ISF intake is inversely associated with BC risk in women at high risk of hereditary BC and that the effect could differ by molecular subtypes.

The Importance of Mandatory COVID-19 Diagnostic Testing Prior to Release from Quarantine.

A 14-day quarantine is implemented in many countries in response to the coronavirus disease pandemic. Korea implemented a mandatory quarantine for those who had close contact with infected patients and those returning from abroad. The present study explored the implications of mandatory coronavirus disease 2019 testing before releasing individuals from the 14-day quarantine in Incheon, Korea. From February 11 to July 5, 2020, 19,296 people were self-quarantined, and 56 (0.3%) of them were confirmed cases of COVID-19. Twenty (35.7%) were identified through the reporting of symptoms during quarantine, and 32 (57.1%) were identified using mandatory pre-release RT-PCR tests. Among the 32, 14 (25%) individuals reported mild symptoms and 18 (32.1%) were asymptomatic. It is suggested that mandatory diagnostic testing prior to release and the symptom-based surveillance after the 14-day quarantine may help control delayed or asymptomatic COVID-19 cases.