Validation of self-reported morbidities of the Korean Atomic Bomb Survivor Cohort.

Objectives: This study aimed to evaluate the agreement of disease status collected through a survey of the Korean Atomic Bomb Survivor Cohort (K-ABC), compared with medical claim records from the Korean National Health Insurance Service (NHIS) database and the Korean Central Cancer Registry (KCCR). Methods: Data on the lifetime physician-diagnosed morbidities of 1,215 K-ABC participants were collected through an interviewer-administered questionnaire between 2020 and 2022. Survey data were linked to the NHIS and KCCR databases. Eleven diseases were included for validation. We evaluated the following indicators: sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, the area under the curve (AUC), and the kappa coefficient. Results: The mean (standard deviation) age was 62.1 (18.7) years, and 42.6% of the participants were aged ≥70 years. Hypertension and cataracts showed the highest prevalence rates (33.8% and 28.8%, respectively). Hypertension, diabetes, and cancer demonstrated high sensitivity (>0.8) and specificity (>0.9), whereas diabetes, cancer, myocardial infarction, angina pectoris, and asthma exhibited high accuracy (>0.9). In contrast, arthritis, allergic rhinitis, and asthma showed low sensitivity (<0.4) and kappa values (<0.3). In the participants aged ≥70 years, the kappa value was ≥0.4 for all diseases except arthritis, allergic rhinitis, and asthma. Conclusion: The results from this initial analysis showed relatively high agreement between the survey and NHIS/KCCR databases, especially for hypertension, diabetes, and cancer. Our findings suggest that the information on morbidities collected through the questionnaires in this cohort was valid for both younger and older individuals.

Accounting for time-varying exposures and covariates in the relationship between obesity and diabetes: analysis using parametric g-formula.

BACKGROUND: Previous studies investigating the association between obesity and diabetes often did not consider the role of time-varying covariates affected by previous obesity status. This study quantified the association between obesity and diabetes using parametric g-formula. METHODS: We included 8924 participants without diabetes from the Korean Genome and Epidemiology Study-Ansan and Ansung study(2001-2002)-with up to the seventh biennial follow-up data from 2015 to 2016. Obesity status was categorised as normal (body mass index (BMI) <23.5 kg/m2), overweight (23.5-24.9 kg/m2), obese 1 (25.0-27.4 kg/m2) and obese 2 (≥27.5 kg/m2). Hazard ratios (HRs) comparing baseline or time-varying obesity status were estimated using Cox models, whereas risk ratio (RR) was estimated using g-formula. RESULTS: The Cox model for baseline obesity status demonstrated an increased risk of diabetes in overweight (HR 1.85; 95% CI=1.48-2.31), obese 1 (2.40; 1.97-2.93) and obese 2 (3.65; 2.98-4.47) statuses than that in normal weight status. Obesity as a time-varying exposure with time-varying covariates had HRs of 1.31 (1.07-1.60), 1.55 (1.29-1.86) and 2.58 (2.14-3.12) for overweight, obese 1 and obese 2 statuses. Parametric g-formula comparing if everyone had been in each obesity category versus normal over 15 years showed increased associations of RRs of 1.37 (1.34-1.40), 1.78 (1.76-1.80) and 2.42 (2.34-2.50). CONCLUSIONS: Higher BMI classification category was associated with increased risk of diabetes after accounting for time-varying covariates using g-formula. The results from g-formula were smaller than when considering baseline obesity status only but comparable with the results from time-varying Cox model.

Mammographic breast features and risk of cardiovascular diseases in korean women.

BACKGROUND: There is a growing amount of evidence on the association between cardiovascular diseases (CVDs) and breast calcification. Thus, mammographic breast features have recently gained attention as CVD predictors. OBJECTIVE: This study assessed the association of mammographic features, including benign calcification, microcalcification, and breast density, with cardiovascular diseases. METHODS: This study comprised 6,878,686 women aged ≥40 who underwent mammographic screening between 2009 and 2012 with follow-up until 2020. The mammographic features included benign calcification, microcalcification, and breast density. The cardiovascular diseases associated with the mammographic features were assessed using logistic regression. RESULTS: The prevalence of benign calcification, microcalcification, and dense breasts were 9.6 %, 0.9 % and 47.3 % at baseline, respectively. Over a median follow-up of 10 years, benign calcification and microcalcification were positively associated with an increased risk of chronic ischaemic heart disease whereas breast density was inversely associated with it; the corresponding aOR (95 % CI) was 1.14 (1.10-1.17), 1.19 (1.03-1.15), and 0.88 (0.85-0.90), respectively. A significantly increased risk of chronic ischaemic heart disease (IHD) was observed among women with benign calcifications (aHR, 1.14; 95 % CI 1.10-1.17) and microcalcifications (aOR, 1.19; 95 % CI 1.06-1.33). Women with microcalcifications had a 1.16-fold (95 % CI 1.03-1.30) increased risk of heart failure. CONCLUSIONS: Mammographic calcifications were associated with an increased risk of chronic ischaemic heart diseases, whereas dense breast was associated with a decreased risk of cardiovascular disease. Thus, the mammographic features identified on breast cancer screening may provide an opportunity for cardiovascular disease risk identification and prevention.

Development of a model to predict the age at breast cancer diagnosis in a global population.

Knowing the mean age at diagnosis of breast cancer (BC) in a country is important for setting up an efficient BC screening program. The aim of this study was to develop and validate a model to predict the mean age at diagnosis of BC at the country level. To develop the model, we used the CI5plus database from the IARC, which contains incidence data for 122 selected populations for a minimum of 15 consecutive years from 1993 to 2012 and data from the World Bank. The standard model was fitted with a generalized linear model with the age of the population, growth domestic product per capita (GDPPC) and fertility rate as fixed effects and continent as a random effect. The model was validated in registries of the Cancer Incidence in Five Continents that are not included in the CI5plus database (1st validation set: 1950-2012) and in the most recently released volume (2nd validation set: 2013-2017). The intercept of the model was 30.9 (27.8-34.1), and the regression coefficients for population age, GDPPC and fertility rate were 0.55 (95% CI: 0.53-0.58, p < 0.001), 0.46 (95% CI: 0.26-0.67, p < 0.001) and 1.62 (95% CI: 1.42-1.88, p < 0.001), respectively. The marginal R2 and conditional R2 were 0.22 and 0.81, respectively, suggesting that 81% percent of the variance in the mean age at diagnosis of BC was explained by the variance in population age, GDPPC and fertility rate through linear relationships. The model was highly accurate, as the correlations between the predicted age from the model and the observed mean age at diagnosis of BC were 0.64 and 0.89, respectively, and the mean relative error percentage errors were 5.2 and 3.1% for the 1st and 2nd validation sets, respectively. We developed a robust model based on population age and continent to predict the mean age at diagnosis of BC in populations. This tool could be used to implement BC screening in countries without prevention programs.

Glycemic status, insulin resistance, and mortality from lung cancer among individuals with and without diabetes.

BACKGROUND: The effects of glycemic status and insulin resistance on lung cancer remain unclear. We investigated the associations between both glycemic status and insulin resistance, and lung cancer mortality, in a young and middle-aged population with and without diabetes. METHODS: This cohort study involved individuals who participated in routine health examinations. Lung cancer mortality was identified using national death records. Cox proportional hazards models were used to calculate hazard ratios (HRs) with 95% CIs for lung cancer mortality risk. RESULTS: Among 666,888 individuals (mean age 39.9 ± 10.9 years) followed for 8.3 years (interquartile range, 4.6-12.7), 602 lung cancer deaths occurred. Among individuals without diabetes, the multivariable-adjusted HRs (95% CI) for lung cancer mortality comparing hemoglobin A1c categories (5.7-5.9, 6.0-6.4, and ≥ 6.5% or 39-41, 42-46, and ≥ 48 mmol/mol, respectively) with the reference (< 5.7% or < 39 mmol/mol) were 1.39 (1.13-1.71), 1.72 (1.33-2.20), and 2.22 (1.56-3.17), respectively. Lung cancer mortality was associated with fasting blood glucose categories in a dose-response manner (P for trend = 0.001) and with previously diagnosed diabetes. Insulin resistance (HOMA-IR ≥ 2.5) in individuals without diabetes was also associated with lung cancer mortality (multivariable-adjusted HR, 1.41; 95% CI, 1.13-1.75). These associations remained after adjusting for changing status in glucose, hemoglobin A1c, insulin resistance, smoking status, and other confounders during follow-up as time-varying covariates. CONCLUSIONS: Glycemic status within both diabetes and prediabetes ranges and insulin resistance were independently associated with an increased risk of lung cancer mortality.

Mental COP: Mental Health Cohort Of Police officers in Korea.

PURPOSE: This cohort study addresses the need for comprehensive and longitudinal research on police officers' mental health, focusing on the relationship between occupational factors, individual characteristics and mental health status or suicidality. The Mental COP (Mental health Cohort Of Police officers in Korea) research provides important insights by tracking new police officers over time, contributing to evidence-based interventions and policies to improve their overall mental health and working conditions. PARTICIPANTS: Mental Cop is a prospective open cohort study designed for new police officers for police recruitment, expected to graduate after 8 months of education at the Central Police Academy. To date, 6752 individuals have completed the baseline survey and are enrolled in the cohort. FINDING TO DATE: The study data in Mental COP covered a wide range of issues for first responders, including personal factors, various mental health problems, occupational factors and measured biomarkers of allostatic load, including Heart Rate Variability. The main findings indicate a lower prevalence of mental health problems among those selected as new police officers compared with the general population with notable gender differences. Therefore, closer monitoring of women is required. Furthermore, the study revealed cohort-based differences in mental health, highlighting increased risk related to occupational factors (field training) and the management of vulnerable groups. FUTURE PLANS: Another wave of Mental COP is scheduled for December 2023, with plans for future cohort expansion. Additionally, it will establish a more comprehensive and systematic scientific framework for future investigations by integrating broader medical examinations and National Health Insurance Service Data.

Risk Factors and Mortality Among Women With Interval Breast Cancer vs Screen-Detected Breast Cancer.

Importance: The risk factors for interval breast cancer (IBC) compared with those for screen-detected breast cancer (SBC) and their association with mortality outcomes have not yet been evaluated among Korean women. Objective: To evaluate risk factors associated with IBC and survival among Korean women with IBC compared with those with SBC. Design, Setting, and Participants: This retrospective cohort study used data from the Korean National Health Insurance Service Database. Women who participated in a national mammographic breast cancer screening program between January 1, 2009, and December 31, 2012, were included. Mortality outcomes were calculated from the date of breast cancer diagnosis to the date of death or December 31, 2020. Data were analyzed from March 1 to June 30, 2023. Exposure: Breast cancer diagnosed within 6 to 24 months after a negative screening result (ie, IBC) or within 6 months after a positive screening result (ie, SBC). Main Outcomes and Measures: Risk factors and survival rates for IBC and SBC. Results: This study included 8702 women with IBC (mean [SD] age, 53.3 [8.6] years) and 9492 women with SBC (mean [SD] age, 54.1 [9.0] years). Compared with SBC, the probability of IBC decreased as mammographic density increased. Lower body mass index, menopausal status, hormone replacement therapy (HRT) use, and lack of family history of breast cancer were associated with a higher likelihood of IBC. When stratified by detection time, younger age at breast cancer diagnosis and family history of breast cancer were associated with an increased likelihood of IBC diagnosed at 6 to 12 months but a decreased likelihood of IBC diagnosed at 12 to 24 months. Overall mortality of IBC was comparable with SBC, but total mortality and cancer-related mortality of IBC diagnosed between 6 and 12 months was higher than that of SBC. Conclusions and Relevance: The findings of this cohort study suggest that breast density, obesity, and HRT use were associated with IBC compared with SBC. These findings also suggest that higher supplemental breast ultrasound use among Korean women, especially those with dense breasts, could be attributed to a lower incidence of IBC among women with dense breasts compared with women with SBC, due to greater detection. Finally, overall mortality of IBC was comparable with that of SBC.

Association between obesity and cancer risk in adults with HIV in Korea.

INTRODUCTION: This study aimed to investigate the association between obesity and cancer risk as well as site-specific cancer risks in adults with HIV using a nationwide health screening database in Korea. METHODS: Of the 16,671 adults with a new diagnosis of HIV from 2004 to 2020, 456 incident cancer cases and 1814 individually matched controls by sex, year of birth, year of HIV diagnosis, and follow-up duration (1 : 4 ratio) were included in this nested case-control study. The association between obesity (BMI ≥25 kg/m 2 ) and cancer risks was estimated and presented as odds ratios (ORs) and 95% confidence intervals (95% CIs). RESULTS: Of the 456 cancer incident cases, there were 146 AIDS-defining cancer cases and 310 non-AIDS-defining cancer cases. Compared with nonobese adults with HIV, obese adults with HIV were at higher risk of non-AIDS-defining cancer (OR = 1.478, 95% CI = 1.118-1.955). Otherwise, the overall risk of AIDS-defining cancer (OR = 0.816, 95% CI = 0.520-1.279) and each type of AIDS-defining cancer (Kaposi sarcoma and non-Hodgkin's lymphoma) were not high in obese adults with HIV. Of the specific types of non-AIDS-defining cancers, obesity was associated with an increased risk of colorectal cancer (OR = 3.090, 95% CI = 1.110-8.604) and liver, bile duct, and pancreatic cancers (OR = 2.532, 95% CI = 1.141-5.617). CONCLUSION: Obesity, which is one of the important health concerns in HIV management, was associated with an increased risk of non-AIDS-defining cancer but not AIDS-defining cancer.

Adiposity, Body Composition Measures, and Breast Cancer Risk in Korean Premenopausal Women.

Objective: To investigate the association between body composition parameters and breast cancer (BC) risk in premenopausal women. Design, Setting, and Participants: Prospective cohort study using data from the Kangbuk Samsung Cohort Study. Participants were women aged 20 to 54 years who were enrolled from 2011 to 2019 and followed up for BC development until December 31, 2020. Data were analyzed from June to August 2023. Exposures: Trained nurses conducted anthropometric measurements and assessed body composition using segmental bioelectric impedance analysis. The analysis encompassed adiposity measures such as body mass index (BMI), waist circumference, and body composition parameters, including muscle mass, fat mass, ratio of muscle mass to weight, ratio of fat mass to weight, and fat mass index. Main outcomes and measures: Adjusted hazard ratios (aHR) for BC during the follow-up period. Results: Among 125 188 premenopausal women, the mean (SD) age was 34.9 (6.3) years. During a mean (range) follow-up of 6.7 (0.5-9.9) years, 1110 incident BC cases were identified. The mean (SD) BMI and waist circumference were 21.6 (3.1) and 75.3 (8.2) cm, respectively. Higher BMI and waist circumference were associated with decreased risk, with an aHR of 0.89 (95% CI, 0.84-0.95) per SD increase in BMI and 0.92 (95% CI, 0.86-0.98) per SD increase in waist circumference. A higher ratio of fat mass to weight was associated with decreased BC risk (aHR, 0.92; 95% CI, 0.86-0.99 per SD increase), whereas the opposite trend was observed for the ratio of muscle mass to weight, with an aHR of 1.08 (95% CI, 1.02-1.15) per SD increase. The results remained consistent even after additional adjustments for height in the model. The fat mass index was also inversely associated with BC risk, with an HR of 0.90 (95% CI, 0.85-0.97) per SD increase. Conclusions and Relevance: In this cohort study of premenopausal women, a higher level of adiposity, represented by increased BMI, waist circumference, and fat mass, was consistently associated with decreased breast cancer risk. Conversely, muscle mass and its ratio to weight displayed opposite or inconsistent patterns. These findings suggest an inverse association between excess adiposity and the risk of BC in premenopausal women, confirming earlier findings that BMI is an indirect measure of adiposity.

Ex vivo kidney machine perfusion: meta-analysis of randomized clinical trials.

BACKGROUND: Machine perfusion is an organ preservation strategy used to improve function over simple storage in a cold environment. This article presents an updated systematic review and meta-analysis of machine perfusion in deceased donor kidneys. METHODS: RCTs from November 2018 to July 2023 comparing machine perfusion versus static cold storage in kidney transplantation were evaluated for systematic review. The primary outcome in meta-analysis was delayed graft function. RESULTS: A total 19 studies were included, and 16 comparing hypothermic machine perfusion with static cold storage were analysed. The risk of delayed graft function was lower with hypothermic machine perfusion (risk ratio (RR) 0.77, 95% c.i. 0.69 to 0.86), even in kidneys after circulatory death (RR 0.78, 0.68 to 0.90) or brain death (RR 0.73, 0.63 to 0.84). Full hypothermic machine perfusion decreased the risk of delayed graft function (RR 0.69, 0.60 to 0.79), whereas partial hypothermic machine perfusion did not (RR 0.92, 0.69 to 1.22). Normothermic machine perfusion or short-term oxygenated hypothermic machine perfusion preservation after static cold storage was equivalent to static cold storage in terms of delayed graft function and 1-year graft survival. CONCLUSION: Hypothermic machine perfusion reduces delayed graft function risks and normothermic approaches show promise.

Association between low-dose aspirin and the risk of gastric cancer and adenoma according to a family history of gastric cancer.

This study aimed to evaluate the association between low-dose aspirin use and the risk of GC and gastric adenoma according to a family history of GC. We conducted a population-based study of 7,596,003 participants screened for GC between 2013 and 2014. Aspirin users and non-users were matched in a 1:1 ratio through propensity score matching (PSM). After PSM, 51,818 participants with a family history of GC and 359,840 without a family history of GC were analyzed (mean follow-up periods: 4.9 ± 0.8 and 4.8 ± 0.8 years, respectively). In patients with a family history of GC, aspirin use was significantly associated with a reduced risk of GC (adjusted hazard ratio [aHR]=0.80; 95 % confidence interval [CI]=0.65-0.995) and gastric adenoma (aHR=0.81; 95% CI=0.69-0.94). In those without a family history of GC, aspirin use was associated with a reduced risk of gastric adenoma (aHR = 0.92; 95 % CI = 0.86-0.98), but not with that of GC (aHR = 0.99; 95 % CI = 0.90-1.08). Low-dose aspirin use was associated with a reduced risk of gastric adenoma, regardless of a family history of GC, and may play a role in the early stages of gastric carcinogenesis. However, the association between aspirin and GC was only observed in those with a family history of GC.

An Epidemiological Study on Legionnaires' Disease in Gyeonggi Province, Korea: Occurrence, Infection Routes, and Risk Factors for Mortality (2016-2022).

Background and Objectives: Legionnaires' disease (LD) is an acute respiratory disease with increasing annual numbers of reported domestic and global cases. This study aimed to establish foundational data for the prevention and control of LD by investigating the occurrence and infection routes of reported and suspected cases of LD in Gyeonggi Province, Korea, from January 2016 to December 2022, and by and analyzing the risk factors for death. Materials and Methods: A sex-and-age standardization was performed on LD patients and suspected cases reported in Gyeonggi Province. The monthly average number of confirmed cases was visualized using graphs, and a survival analysis was performed using Kaplan-Meier survival curves. The mortality risk ratio was estimated using the Cox proportional hazards model. Results: The incidence of LD in Gyeonggi Province mirrored the national trend, peaking in July with the highest number of confirmed and suspected cases. While there was no significant difference in survival rates by age, the survival rate was higher for suspected cases when analyzed separately. Comparing the death ratio by infection route, nosocomial infections showed the highest death ratio, and intensive care unit (ICU) admission and the presence of coinfections were significantly correlated with mortality. Factors such as nosocomial infection, admission within 1 to 3 days following diagnosis, and the development of complications were factors contributing to a higher risk of death. Conclusions: The general characteristics of patients with LD were similar to those suggested by previous studies. The proportion of community-acquired infections was lower than in previous studies, but the length of hospital stay was similar for survivors and the deceased, and the mortality rate within 30 days after diagnosis was higher for nosocomial infections. In conclusion, nosocomial infection, a period of up to 3 days from admission to diagnosis, and complications were significantly related to the mortality rate of LD.

Associations between breast cancer risk factors and mammographic breast density in a large cross-section of Korean women.

BACKGROUND: We investigated the association between established risk factors for breast cancer and mammographic breast density in Korean women. METHODS: This large cross-sectional study included 8 460 928 women aged >40 years, who were screened for breast cancer between 2009 and 2018. Breast density was assessed using the Breast Imaging Reporting and Data System. This study used multiple logistic regression analyses of age, BMI, age at menarche, menopausal status, menopausal age, parity, breastfeeding status, oral contraceptive use, family history of breast cancer, physical activity, smoking, drinking and hormone replacement therapy use to investigate their associations with mammographic breast density. Analyses were performed using SAS software. RESULTS: Of 8 460 928 women, 4 139 869 (48.9%) had nondense breasts and 4 321 059 (51.1%) had dense breasts. Factors associated with dense breasts were: earlier age at menarche [<15 vs. ≥15; adjusted odds ratio (aOR), 1.18; 95% confidence interval (CI), 1.17-1.18], premenopausal status (aOR, 2.01; 95% CI, 2.00-2.02), later age at menopause (≥52 vs. <52; aOR, 1.23; 95% CI, 1.22-1.23), nulliparity (aOR, 1.64; 95% CI, 1.63-1.65), never breastfed (aOR, 1.23; 95% CI, 1.23-1.24) and use of hormone replacement therapy (aOR, 1.29; 95% CI, 1.28-1.29). Women with a higher BMI and the use of oral contraceptives were more likely to have nondense breasts. CONCLUSION: Lower BMI, reproductive health and behavioral factors were associated with dense breasts in Korean women. Additional research should investigate the relationship between mammographic breast density, breast cancer risk factors and breast cancer risk.

Strategies to Improve Smoking Cessation for Participants in Lung Cancer Screening Program: Analysis of Factors Associated with Smoking Cessation in Korean Lung Cancer Screening Project (K-LUCAS).

PURPOSE: Smoking cessation intervention is one of the key components of successful lung cancer screening program. We investigated the effectiveness and related factors of smoking cessation services provided to the participants in a population-based lung cancer screening trial. MATERIALS AND METHODS: The Korean Lung Cancer Screening Project (K-LUCAS) is a nationwide, multi-center lung cancer screening trial that evaluates the feasibility of implementing population-based lung cancer screening. All 5,144 current smokers who participated in the K-LUCAS received a mandatory smoking cessation counseling. Changes in smoking status were followed up using a telephone survey in 6 months after lung cancer screening participation. The lung cancer screening's impact on smoking cessation is analyzed by variations in the smoking cessation interventions provided in screening units. RESULTS: Among 4,136 survey responders, participant's motivation to quit smoking increased by 9.4% on average after lung cancer screening. After 6 months from the initial screening, 24.3% of participants stopped smoking, and 10.6% of participants had not smoked continuously for at least 6 months after screening. Over 80% of quitters stated that participation in lung cancer screening motivated them to quit smoking. Low-cost public smoking cessation program combined with lung cancer screening increased the abstinence rates. The smokers were three times more likely to quit smoking when the smoking cessation counseling was provided simultaneously with low-dose computed tomography screening results than when provided separately. CONCLUSION: A mandatory smoking cessation intervention integrated with screening result counselling by a physician after participation in lung cancer screening could be effective for increasing smoking cessation attempts.

Causes of death and associated factors with death after liver transplantation: a nationwide database study.

BACKGROUND/AIMS: This study investigated overall, 1-year, and 5-year mortality rate, the causes of death, and associated factors with death in liver transplantation recipients. METHODS: A total of 11,590 liver transplant recipients identified from National Health Insurance Service database between 2006 and 2017 were included. Factors associated with all-cause of death were analyzed by Cox proportional regression models. Cumulative mortality rate according to the underlying indication was estimated by Kaplan-Meier method. RESULTS: The 12-year survival rate for all liver transplant recipients was 68%. In the overall, 1-year, and 5-year mortality of liver transplant recipients, hepatic death was the highest contributing risk, accounting for >65% of the causes of death. Deaths from cirrhosis and liver failure accounted for a high proportion of deaths within 1 year after transplantation, and deaths from malignant tumors such as hepatocellular carcinoma were high among late-stage deaths. DISCUSSION: Although the most common cause of death from liver transplantation is due to primary disease, there was a difference in the pattern of major causes of death according to the period from transplantation to death. If appropriate medical intervention is performed at each period after transplantation, the survival rate can be improved.

Longitudinal Changes in Smoking Behaviors and Cancer-Related Mortality Risk in Middle-Aged Korean Women.

PURPOSE: This study investigated association between smoking habit change and cancer-related mortality risk in Korean women. MATERIALS AND METHODS: Study population were women aged ≥ 40 years who underwent two biennial cancer screenings during 2009-2012 and were followed up until 2020. Participants were grouped into sustained nonsmokers, sustained quitters, new quitters, relapsers/smoking initiators, and sustained smokers. Outcomes included all-cause and cancer-related deaths. Cox regression and competing risk analysis was used to assess association between smoking habit change and mortality risk. RESULTS: Of 2,892,590 women, 54,443 death cases were recorded (median follow-up of 9.0 years). Compared with sustained nonsmokers, mortality risk from all causes and cancer-related causes increased in all other smoking groups. Cancer-related risk increased 1.22-fold among sustained quitters (95% confidence interval [CI], 1.10 to 1.36), 1.56-fold (95% CI, 1.40 to 1.75) in new quitters, 1.40-fold (95% CI, 1.21 to 1.62) in relapsers/smoking initiators, and 1.61-fold (95% CI, 1.46 to 1.78) in sustained smokers compared with sustained nonsmokers. Women who were sustained smokers with higher smoking intensity had a higher mortality risk in terms of hazard ratios compared to nonsmokers (< 5 pack-years 2.12-fold, 5-10 pack-years 2.15-fold, and > 10 pack-years 2.27-fold). CONCLUSION: Quitting smoking earlier is critical for preventing death from all causes and cancer among female smokers.

Temporal Trend in Uptake of the National General Health Checkups and Cancer Screening Program among Korean Women with Breast Cancer.

PURPOSE: This study assessed the temporal trends of uptake of national general health and cancer screening among women with breast cancer in Korea between 2009 and 2016. MATERIALS AND METHODS: We retrospectively analyzed the claims data from the Korean National Health Insurance Service database. Participants included 101,403 breast cancer patients diagnosed between 2009 and 2016. Information on participation in national screening programs, including breast cancer screening, general health, and gastric, colorectal, and cervical cancers, up to 2020 was collected. Screening participation rates within the first 2 and 5 years postdiagnosis were calculated by diagnosis year and fitted with joinpoint regression models to assess temporal trends. RESULTS: Overall, the participation rate in breast cancer screening within 2 years postdiagnosis increased from 10.9% to 14.0% from 2009-2016, with an annual percentage change (APC) of 3.7% (p < 0.05). The participation rate in breast cancer screening was lower than that in general health checkup and screening for other cancers within 2 and 5 years postdiagnosis. A steady increase in screening trends was also observed for general health, gastric, colorectal, and cervical cancers, with APC of 5.3%, 5.7%, 6.9%, and 7.6% in the 2-year postdiagnosis rate, and APC of 3.6%, 3.7%, 3.7%, and 4.4% in 5-year postdiagnosis rate, respectively. The screening rate was highest among age groups 50-59 and 60-69 in 2009 and significant upward trends were observed in all age groups for general health checkup and gastric, colorectal, and cervical cancer screening. CONCLUSION: Among female breast cancer survivors in Korea, the uptake rate of screenings for general health and various cancers, including breast, gastric, colorectal, and cervical cancers, has shown a gradual increase in recent years.

Secondary Malignancies in Multiple Myeloma in Korean Patients: A Nationwide Population-Based Study.

PURPOSE: This study investigated the incidence of secondary malignancy in multiple myeloma (MM) patients compared with that in the general population using a population-based database covering all residents in Korea. MATERIALS AND METHODS: Based on the national health insurance system in Korea, all people primarily diagnosed with MM between January 1, 2010 to December 31, 2018 were identified. A total of 9,985 MM patients aged ≥ 20 years in Korea were included. RESULTS: Among them, 237 (2.4%) developed secondary malignancies by 2018. The standardized incidence rates (SIRs) of all secondary malignancies in MM patients were 0.87 (95% confidence interval [CI], 0.76 to 0.98), with a higher incidence of hematologic malignancies than in the general population with an SIR of 3.80 (95% CI, 2.61 to 5.00). The incidence rates of both lymphoid malignancy (SIR, 3.56; 95% CI, 2.31 to 4.82) and myeloid malignancy (SIR, 3.78; 95% CI, 1.16 to 6.39) were higher in MM patients than in the general population. In contrast, a lower incidence of solid cancer was observed in MM patients than in the general population (SIR, 0.76, 95% CI, 0.65 to 0.86). There was no significant difference in survival in MM patients without secondary malignancies, with hematologic malignancy, and with solid cancer (p=0.413). CONCLUSION: MM patients had a greater risk of secondary malignancies, especially hematologic malignancies, than the general population. Future studies with a focus on analyzing patients' history, treatment details, and genetic information in various stages of MM patients are needed to better understand the mechanism behind this increased risk.

A systematic review and meta-analysis of blood transfusion rates during liver resection by country.

Purpose: This study aimed to determine the blood transfusion rates during liver resection by country to prepare a basis for patient blood management policy. Methods: Relevant articles from January 2020 to December 2022 were identified through an electronic database search. Meta-analyses were performed using fixed- or random-effects models. Study heterogeneity was assessed using the Q-test and I2 test. Publication bias was evaluated using funnel plots and Egger's and Begg's tests. Results: Of 104 studies (103,778 participants), the mean transfusion rate was 16.20%. Korea's rate (9.72%) was lower than Western (14.97%) and other Eastern nations (18.61%). Although open surgery rates were alike (approximately 25%) globally, Korea's minimally invasive surgery rate was lower (6.28% vs. ≥10%). Odds ratios (ORs) indicated a higher transfusion risk in open surgeries than minimally invasive surgery, especially in Korea (8.82; 95% confidence interval [CI], 5.55-14.02) compared to other Eastern (OR, 2.57) and Western countries (OR, 2.20). For liver resections due to hepatocellular carcinoma and benign diseases, Korea's rates (10.86% and 15.62%) were less than in Eastern (18.90% and 29.81%) and Western countries (20.15% and 25.22%). Conclusion: Korea showed a lower transfusion rate during liver resection than other countries. In addition to the patient's characteristics, including diagnosis and surgical methods, differences in the medical environment affect blood transfusion rates during liver resection.

Mammographic breast density and cardiovascular disease risk in women.

AIMS: We aimed to determine the predictive role of mammographic breast density in addition to the Framingham Risk Score (FRS) on subsequent CVD events in women. METHODS AND RESULTS: This cohort study included 4,268,579 women aged ≥40 years who underwent mammography screening between 2009 and 2010 with follow-up until 2020. Breast density was reported following the Breast Imaging Reporting and Data System. Primary outcomes included coronary heart disease, cerebrovascular disease, peripheral arterial disease, and heart failure. The incremental predictive ability of breast density added to the FRS model was assessed using the ROC and net reclassification index (NRI) among all women and strata based on FRS risk categories (<5% as low-risk, 5%-10% as moderate-risk, and ≥10% as high-risk). In total, 135,475 CVD events were recorded after a median follow-up of 10.9 years. A lower category of breast density was associated with a higher risk of CVD. Compared to the extremely dense breast group, the hazard ratios (95% CI) for CVDs were 1.12 (1.09-1.14), 1.19 (1.17-1.22), and 1.29 (1.26-1.32) in women with heterogeneously dense, scattered fibroglandular densities, and almost entirely fat breast density, respectively. Adding breast density to the FRS showed a slight improvement in AUROC but a modest improvement in NRI; the C-statistic difference was 0.083% (95% CI 0.069-0.096) with a 7.15% (6.85-7.69) increase in NRI, with the strongest improvement observed in the low-risk group. CONCLUSIONS: Mammographic breast density is an independent predictor of incident CVD among women. The addition of mammographic breast density to FRS improves the prediction of CVDs, especially in low-risk individuals.