Cost-effectiveness of expanding national health insurance coverage for composite resin restorations in cancer patients in South Korea.

OBJECTIVES: Cancer patients often have compromised oral health, making them vulnerable to severe dental caries and restoration failures. Due to the nature of cervical or anterior caries in cancer patients, the use of adequate restorative materials is important. However, public dental insurance coverage for composite treatments varies among countries and only glass ionomer cements (GICs) are covered in all age groups in South Korea. This study examined the cost-effectiveness of expanding national health insurance coverage to include resin composite (RC) restorations as compared with GIC in cancer patients. METHODS: Data from cancer patients who received direct restoration using GIC were identified from the National Health Screening Cohort. The relative effect of RC compared to GIC was determined through a meta-analysis, which was then utilized in calculating corresponding transition probabilities within a multi-state model. A Markov-chain Monte Carlo microsimulation was performed to estimate useful life-years and total treatment costs at the tooth level. The incremental cost-effectiveness ratio (ICER) of RC versus GIC was calculated, considering scenarios with and without expanded national health insurance coverage. The robustness of the results was confirmed through various sensitivity analyses. RESULTS: Between the two materials, RC resulted in a 0.4-year longer useful life. From a limited societal perspective, it cost $9.6 less with expanded coverage but $24.3 more without expansion, resulting in an ICER of -$25.2 and $63.9 per tooth-year, respectively. From a patient's perspective, the ICER values were -$72.7 versus $138.8 per tooth-year, respectively, translating into $200 more in savings with the expansion. Various sensitivity analyses consistently demonstrated a smaller ICER when insurance coverage was expanded. CONCLUSIONS: The expansion of national health insurance coverage to include RC restorations for cancer patients appears to be clearly cost-effective. This emphasizes the need for further policy considerations to ensure access to dental care for cancer patients. CLINICAL SIGNIFICANCE: Timely management of dental caries is crucial for cancer patients, as untreated caries can escalate into severe oral conditions, negatively impacting treatment outcomes and increasing care costs. Expanding a national health insurance coverage for cancer patients in the treatment of early dental lesions is necessary to prevent advanced dental diseases.

Age at menarche by birth cohort: A pooled analysis of half a million women in Asia.

OBJECTIVES: To evaluate changes in the age at menarche in Asian populations. STUDY DESIGN: Retrospective cohort study. METHODS: We included 548,830 women from six countries in Asia. The data were sourced from 20 cohorts participating in the Asia Cohort Consortium (ACC) and two additional cohort studies: Japan Multi-institutional Collaborative Cohorts (J-MICC), and Japan Nurse Health Study (JNHS) with data on age at menarche. Joinpoint regression was used to evaluate changes in age at menarche by birth year and by country. RESULTS: The study includes data from cohorts in six Asian countries namely, China, Iran, Japan, Korea, Malaysia and Singapore. Birth cohorts ranged from 1873 to 1995. The mean age of menarche was 14.0 years with a standard deviation (SD) of 1.4 years, ranged from 12.6 to 15.5 years. Over 100 years age at menarche showed an overall decrease in all six countries. China showed a mixed pattern of decrease, increase, and subsequent decrease from 1926 to 1960. Iran and Malaysia experienced a sharp decline between about 1985 and 1990, with APC values of -4.48 and -1.24, respectively, while Japan, South Korea, and Singapore exhibited a nearly linear decline since the 1980s, notably with an APC of -3.41 in Singapore from 1993 to 1995. CONCLUSIONS: Overall, we observed a declining age at menarche, while the pace of the change differed by country. Additional long-term observation is needed to examine the contributing factors of differences in trend across Asian countries. The study could serve as a tool to strengthen global health campaigns.

Genetically predicted dietary intake and risks of colorectal cancer: a Mendelian randomisation study.

BACKGROUND: Effects of confounders on associations between diet and colorectal cancer (CRC) in observational studies can be minimized in Mendelian randomization (MR) approach. This study aimed to investigate observational and genetically predicted associations between dietary intake and CRC using one-sample MR. METHODS: Using genetic data of over 93 million variants, we performed a genome-wide association study to find genomic risk loci associated with dietary intake in participants from the UK Biobank. Then we calculated genetic risk scores of diet-related variants and used them as instrumental variables in the two-stage least square MR framework to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) for associations. We also performed observational analyses using age as a time-scale in Cox proportional hazard models. RESULTS: Allele scores were calculated from 399 genetic variants associated with the consumption of of red meat, processed meat, poultry, fish, milk, cheese, fruits, vegetables, coffee, tea, and alcohol in participants from the UK Biobank. In MR analysis, genetically predicted fruit intake was significantly associated with a 21% decreased risk of CRC (HR = 0.79, 95% CI = 0.66-0.95), and there was a marginally inverse association between vegetable intake and CRC (HR = 0.85, 95% CI = 0.71-1.02). However, null findings were observed in multivariable analysis, with HRs (95% CIs) of 0.99 (0.98-1.01) and 0.99 (0.98-1.00) per increment of daily servings of fruits and vegetables, respectively. CONCLUSION: Dietary habits were attributable to genetic variations, which can be used as instrumental variables in the MR framework. Our study supported a causal relationship between fruit intake and a decreased risk of CRC and suggested an effective strategy of consuming fruits in the primary prevention of CRC.

Impact of body mass index and waist-to-hip ratio on mortality in middle-aged Koreans: A prospective cohort study based on a Health Examinees study.

Objectives: We aimed to assess the impact of obesity on mortality in middle-aged Koreans using data from a Health Examinees study. Methods: We used data from the participants who had complete information on body size and gave informed consent for the linkage of their data with the national death certificate data. Cox proportional hazard model was used to estimate the hazard ratios (HRs) and 95% confidence intervals (CIs) of body mass index (BMI) and waist-to-hip ratio (WHR) for all-cause, cardiovascular, and cancer mortality. Results: A total of 115,961 participants were included in the study. The results showed a U-shaped association between BMI and mortality, indicating that both men and women with BMIs of less than 21 kg/m2 and greater than or equal to 30 kg/m2 are at increased risk. The results showed that men with a BMI of less than 18.5 kg/m² had a significantly higher risk of all-cause mortality (adjusted HR: 2.24 [95% CI: 1.73-2.91]) and cardiovascular mortality (2.27 [1.23-4.20]). Similarly, men with a WHR of less than 0.80 (1.38 [1.08-1.77]), 0.90 to less than 0.95 (1.15 [1.02-1.29]), and greater than or equal to 0.95 (1.28 [1.11-1.47]) showed an increased risk of all-cause mortality. In women, a BMI of less than 18 kg/m² was linked to a higher risk of cardiovascular mortality (2.67 [1.13-6.33]). Conclusion: Being underweight was associated with an increased risk of mortality in both sexes, and the lowest risk of death was found in men who were slightly overweight with a BMI of 23-25 kg/m2.

Association of female reproductive and hormonal factors with gallbladder cancer risk in Asia: A pooled analysis of the Asia Cohort Consortium.

The female predominance of gallbladder cancer (GBC) has led to a hypothesis regarding the hormone-related aetiology of GBC. We aimed to investigate the association between female reproductive factors and GBC risk, considering birth cohorts of Asian women. We conducted a pooled analysis of 331,323 women from 12 cohorts across 4 countries (China, Japan, Korea, and Singapore) in the Asia Cohort Consortium. Cox proportional hazard models were used to estimate the hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) to assess the association between reproductive factors (age at menarche, parity, age at first delivery, breastfeeding, and age at menopause) and GBC risk. We observed that a later age at menarche was associated with an increased risk of GBC (HR 1.4, 95% CI 1.16-1.70 for 17 years and older vs. 13-14 years), especially among the cohort born in 1940 and later (HR 2.5, 95% CI 1.50-4.35). Among the cohort born before 1940, women with a later age at first delivery showed an increased risk of GBC (HR 1.56, 95% CI 1.08-2.24 for 31 years of age and older vs. 20 years of age and younger). Other reproductive factors did not show a clear association with GBC risk. Later ages at menarche and at first delivery were associated with a higher risk of GBC, and these associations varied by birth cohort.

Association between reproductive factors with lung cancer incidence and mortality: A pooled analysis of over 308,000 females in the Asia cohort consortium.

Previous studies have investigated the association between reproductive factors and lung cancer risk; however, findings have been inconsistent. In order to assess this association among Asian women, a total of 308,949 female participants from 11 prospective cohorts and four Asian countries (Japan, Korea, China, and Singapore) were included. Cox proportional hazards regression models were used to estimate the hazard ratios (HR) and 95% confidence intervals (CIs). A total of 3,119 primary lung cancer cases and 2247 lung cancer deaths were identified with a mean follow-up of 16.4 years. Parous women had a lower risk of lung cancer incidence and mortality as compared with nulliparous women, with HRs of 0.82 (95% CI = 0.70-0.96) and 0.78 (95% CI = 0.65-0.94). The protective association of parity and lung cancer incidence was greater among ever-smokers (HR = 0.66, 95% CI = 0.49-0.87) than in never-smokers (HR = 0.90, 95% CI = 0.74-1.09) (P-interaction = 0.029). Compared with age at first delivery ≤20 years, older age at first delivery (21-25, ≥26 years) was associated with a lower risk of lung cancer incidence and mortality. Women who ever used hormone replacements had a higher likelihood of developing non-small cell lung cancer (HR = 1.31, 95% CI = 1.02-1.68), compared to those who never used hormone replacements. Future studies are needed to assess the underlying mechanisms, the relationships within these female reproductive factors, and the potential changes in smoking habits over time.

Genome-Wide Interaction Study of Dietary Intake and Colorectal Cancer Risk in the UK Biobank.

Importance: Candidate gene analysis approaches have shown that colorectal cancer (CRC) risk attributable to diet may differ according to genotype. A genome-wide approach further allows for the exploration of underlying pathways for associations between diet and CRC risk across the genome. Objectives: To identify genetic variants that modify diet-CRC associations and to further explore the underlying pathways in the cause of CRC. Design, Setting, and Participants: This nested case-control study used data on White British participants from the prospective cohort UK Biobank. Participants were recruited between March 13, 2006, and October 1, 2010, and data were censored June 25, 2021. Exposures: The average frequency intake of 11 dietary factors in the year preceding baseline was obtained via a touchscreen questionnaire. After quality control for more than 93 million variants of imputed genetic data, 4 122 345 variants remained. Main Outcomes and Measures: Colorectal cancer cases were identified according to the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision. Genome-wide interaction analysis was performed to test interactions between dietary factors and variants using a conditional logistic regression model. Summary statistics of interactions at the variant level were used to calculate empirical P values for interactions at gene and gene-set levels in gene-based and gene-set enrichment analyses. Results: A total of 4686 participants with CRC (mean [SD] age, 60.7 [6.6] years; 2707 men [57.8%]) received a new diagnosis during a median of 12.4 years (IQR, 11.6-13.1 years) of follow-up. Once a case was detected, 3 matched controls were identified, for a total of 14 058 controls (mean [SD] age, 60.4 [6.6] years; 8121 men [57.8%]). A total of 324 variants were identified that interacted with diet consumption at the suggestive threshold (P < 1 × 10-5). In gene-based analysis, aggregation of multiple EPDR1 gene variants was found to interact with fish intake regarding CRC risk. Furthermore, gene-set enrichment analysis found that several sets of protein-coding genes, which were overrepresented with particular functions and pathways, interacted with the consumption of milk (ART), cheese (OR), tea (KRT), and alcohol (PRM and TNP). Conclusions and Relevance: In this nested case-control study, the risk of CRC associated with fish intake was modified by multiple single-nucleotide polymorphisms of the EPDR1 gene. The findings further suggested possible functions and pathways that might link the consumption of milk, cheese, tea, and alcohol with CRC development.

Differential patterns of reproductive and lifestyle risk factors for breast cancer according to birth cohorts among women in China, Japan and Korea.

BACKGROUND: The birth cohort effect has been suggested to influence the rate of breast cancer incidence and the trends of associated reproductive and lifestyle factors. We conducted a cohort study to determine whether a differential pattern of associations exists between certain factors and breast cancer risk based on birth cohorts. METHODS: This was a cohort study using pooled data from 12 cohort studies. We analysed associations between reproductive (menarche age, menopause age, parity and age at first delivery) and lifestyle (smoking and alcohol consumption) factors and breast cancer risk. We obtained hazard ratios (HRs) with 95% confidence intervals (CIs) using the Cox proportional hazard regression analysis on the 1920s, 1930s, 1940s and 1950s birth cohorts. RESULTS: Parity was found to lower the risk of breast cancer in the older but not in the younger birth cohort, whereas lifestyle factors showed associations with breast cancer risk only among the participants born in the 1950s. In the younger birth cohort group, the effect size was lower for parous women compared to the other cohort groups (HR [95% CI] 0.86 [0.66-1.13] compared to 0.60 [0.49-0.73], 0.46 [0.38-0.56] and 0.62 [0.51-0.77]). Meanwhile, a higher effect size was found for smoking (1.45 [1.14-1.84] compared to 1.25 [0.99-1.58], 1.06 [0.85-1.32] and 0.86 [0.69-1.08]) and alcohol consumption (1.22 [1.01-1.48] compared to 1.10 [0.90-1.33], 1.15 [0.96-1.38], and 1.07 [0.91-1.26]). CONCLUSION: We observed different associations of parity, smoking and alcohol consumption with breast cancer risk across various birth cohorts.

A 6-month exercise intervention clinical trial in women: effects of physical activity on multi-omics biomarkers and health during the first wave of COVID-19 in Korea.

BACKGROUND: Coronavirus disease 2019 (COVID-19) was first reported in December 2019 and the first case in Korea was confirmed on January 20, 2020. Due to the absence of therapeutic agents and vaccines, the Korean government implemented social distancing on February 29, 2020. This study aimed to examine the effect of physical activity (PA) on health through changes in multi-omics biomarkers with a 6-month of exercise intervention during the first wave of COVID-19 in Korea. METHODS: Twenty-seven healthy middle-aged women were recruited and 14 subjects completed the exercise intervention. The mean age (± SD) was 46.3 (± 5.33) and the mean BMI (± SD) was 24.9 (± 3.88). A total of three blood and stool samples were collected at enrollment, after period 1, and after period 2 (3-month intervals). The amount of PA was measured with an accelerometer and by questionnaire. Clinical variables were used, including blood pressure, grip strength, flexibility, and blood glucose levels and lipid markers obtained from laboratory tests. The concentration of blood metabolites was measured by targeted metabolomics. Fecal microbiome data were obtained by 16 S rRNA gene amplicon sequencing. RESULTS: During the second half period (period 2), Coronavirus disease 2019 occurred and spread out in Korea, and PA decreased compared with the first half period (period 1) (185.9 ± 168.73 min/week to 102.5 ± 82.30 min/week; p = 0.0101). Blood pressure, hemoglobin A1c (HbA1c), and low-density lipoprotein cholesterol (LDL-C) decreased in period 1 (p < 0.05) and tended to increase again during period 2 (p < 0.05). Forty metabolites were changed significantly during period 1 (FDR p < 0.05), and we found that 6 of them were correlated with changes in blood pressure, HbA1c, and LDL-C via network analysis. CONCLUSIONS: Our results may suggest that exercise improves health through changes in biomarkers at multi-omics levels. However, reduced PA due to COVID-19 can adversely affect health, emphasizing the necessity for sustained exercise and support for home-based fitness to maintain health. TRIAL REGISTRATION: The trial is retrospectively registered on ClinicalTrials.gov (NCT05927675; June 30, 2023).

Assessments of dietary intake and polygenic risk score in associations with colorectal cancer risk: evidence from the UK Biobank.

BACKGROUND: This study aimed to explore the potential interaction between dietary intake and genetics on incident colorectal cancer (CRC) and whether adherence to healthy dietary habits could attenuate CRC risk in individuals at high genetic risk. METHODS: We analyzed prospective cohort data of 374,004 participants who were free of any cancers at enrollment in UK Biobank. Dietary scores were created based on three dietary recommendations of the World Cancer Research Fund (WCRF) and the overall effects of 11 foods on CRC risks using the inverse-variance (IV) method. Genetic risk was assessed using a polygenic risk score (PRS) capturing overall CRC risk. Cox proportional hazard models were used to calculate hazard ratios (HRs) and 95% CIs (confidence intervals) of associations. Interactions between dietary factors and the PRS were examined using a likelihood ratio test to compare models with and without the interaction term. RESULTS: During a median follow-up of 12.4 years, 4,686 CRC cases were newly diagnosed. Both low adherence to the WCRF recommendations (HR = 1.12, 95% CI = 1.05-1.19) and high IV-weighted dietary scores (HR = 1.27, 95% CI = 1.18-1.37) were associated with CRC risks. The PRS of 98 genetic variants was associated with an increased CRC risk (HRT3vsT1 = 2.12, 95% CI = 1.97-2.29). Participants with both unfavorable dietary habits and a high PRS had a more than twofold increased risk of developing CRC; however, the interaction was not significant. Adherence to an overall healthy diet might attenuate CRC risks in those with high genetic risks (HR = 1.21, 95% CI = 1.08-1.35 for high vs. low IV-weighted dietary scores), while adherence to WCRF dietary recommendations showed marginal effects only (HR = 1.09, 95% CI = 1.00-1.19 for low vs. high WCRF dietary scores). CONCLUSION: Dietary habits and the PRS were independently associated with CRC risks. Adherence to healthy dietary habits may exert beneficial effects on CRC risk reduction in individuals at high genetic risk.

Sleep Duration, Comorbidities, and Mortality in Korean Health Examinees: A Prospective Cohort Study.

OBJECTIVES: The association between long sleep duration and mortality is frequently attributed to the confounding influence of comorbidities. Nevertheless, past efforts to account for comorbidities have yielded inconsistent outcomes. The objective of this study was to evaluate this relationship using a large prospective cohort in Korea. METHODS: The study included 114 205 participants from the Health Examinees Study, who were followed for a median of 9.1 years. A composite comorbidity score was developed to summarize the effects of 21 diseases. Using Cox proportional hazards regression, hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause, cancer, and cardiovascular mortality associated with sleep duration were estimated. These estimates were adjusted for socio-demographic factors, lifestyle factors, body mass index, and comorbidity score. Additionally, a stratified analysis by subgroups with and without comorbidities was conducted. RESULTS: Throughout the follow-up period, 2675 deaths were recorded. After all adjustments, an association was observed between a sleep duration of 8 hours or more and all-cause mortality (HR, 1.10; 95% CI, 1.01 to 1.20). However, no such association was detected in the stratified analysis for the subgroups based on comorbidity status. CONCLUSIONS: Long sleep duration was found to be associated with all-cause mortality among Koreans, even after adjusting for comorbidities. Additional studies are required to explore the mechanism underlying the association between sleep duration and major causes of mortality.

Reproductive Factors and Endometrial Cancer Risk Among Women.

Importance: Despite evidence of an association between reproductive factors and endometrial cancer risk, prospective studies have been conducted mainly in non-Asian countries. Objective: To assess the association between reproductive factors, such as number of deliveries, age at menarche, or menopause, and endometrial cancer risk. Design, Setting, and Participants: This cohort study used pooled individual data from 13 prospective cohort studies conducted between 1963 and 2014 in the Asia Cohort Consortium. Participants were Asian women. Data analysis was conducted from September 2019 to April 2023. Exposures: Reproductive factors were assessed using a questionnaire in each cohort. Main Outcomes and Measures: The main outcome was time to incidence of endometrial cancer. A Cox proportional hazards model was used to calculate hazard ratios (HRs) and 95% CIs. Results: A total of 1005 endometrial cancer cases were detected among 332 625 women (mean [SD] age, 54.3 [10.4] years) during a mean (SD) of 16.5 (6.4) years of follow-up. Increasing number of deliveries was associated with a decreased endometrial cancer risk in a dose-response manner (≥5 deliveries vs nulliparous [reference]: HR, 0.37; 95% CI, 0.26-0.53; P for trend < .001). Compared with menarche at younger than 13 years, menarche at 17 years or older had an HR of 0.64 (95% CI, 0.48-0.86; P for trend < .001). Late menopause (age ≥55 years) showed an HR of 2.84 (95% CI, 1.78-4.55; P for trend < .001) compared with the youngest age category for menopause (<45 years). Age at first delivery, hormone therapy, and breastfeeding were not associated with endometrial cancer risk. Conclusions and Relevance: This large pooled study of individual participant data found that late menarche, early menopause, and a higher number of deliveries were significantly associated with a lower risk of endometrial cancer. These convincing results from Asian prospective studies add to the growing body of evidence for the association between reproductive factors and endometrial cancer.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research and Korean Cancer Prevention Guidelines and cancer risk: a prospective cohort study from the Health Examinees-Gem study.

OBJECTIVES: The purpose of this study was to explore the association between adherence to 2 cancer prevention recommendations and cancer risk. METHODS: In total, 104,386 individuals aged 40-69 years old who were recruited between 2004 and 2013 in the Health Examinees-Gem study were included. Adherence scores were constructed based on 8 items from the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations, including body weight, physical activity, diet, alcohol consumption and breastfeeding, and on 6 items from the Korean cancer prevention guidelines (smoking status, eating vegetables and fruits, salty foods, alcohol intake, physical activity, and body weight). A Cox proportional hazards model was used to estimate the associations between adherence scores and the risk of total and 5 major cancers. RESULTS: The multivariable hazard ratio (HR) for total cancer with the high adherence score versus the lowest score (4.25-7.00 vs. 0.00-3.25) for the WCRF/AICR guidelines was 0.91 (95% confidence interval [CI], 0.82 to 1.00) in men. A reduced breast cancer risk was observed among women with the highest score. Men within the highest category of the Korean cancer prevention guideline score (3.25-6.00) had an HR of 0.80 (95% CI, 0.73 to 0.88) for developing total cancer compared to men within the lowest score (0.00-2.50). The higher adherence group among men showed lower risks of developing stomach, colorectal, and lung cancers. CONCLUSIONS: Adhering to guidelines for cancer prevention can help to reduce the risk of developing cancer in Korean men. The association might differ by cancer type and gender.

Bidirectional associations between periodontal disease and systemic diseases: a nationwide population-based study in Korea.

To evaluate the associations of periodontal disease (PD) with systemic diseases, including diabetes mellitus (DM) and cardiovascular disease (CVD), as well as the reciprocal association. The CVD included the cases of coronary heart disease and heart failure. A prospective study was conducted from 2007 to 2019 using linked data from three databases in Korea. Three separate study groups were formed to individually determine the risks of PD (n = 10,533), DM (n = 14,523) and CVD (n = 14,315). All diseases were confirmed based on physicians' diagnoses using medical records and self-reports. Cox proportional hazard regression was applied with 95% confidence intervals (CIs) to obtain hazard ratios (HRs). PD was significantly associated with an elevated risk of DM (HR [95% CI]: 1.22 [1.07-1.39]) after full adjustment for age, sex, lifestyle factors, body mass index, dental behaviour and CVD. PD was also found to increase the risk of CVD (1.27 [1.03-1.57]), whereas CVD increased the risk of PD (1.20 [1.09-1.32]) after full adjustment for other covariates including DM. This study found a bidirectional association between PD and CVD, as well as a positive association of PD with DM.

Impact of pre- and post-diagnosis physical activity on the mortality of patients with cancer: Results from the Health Examinees-G study in Korea.

BACKGROUND: Physical activity (PA) is recommended to improve the survival of cancer patients. However, the prognostic impact of specific PAs is not well understood. Therefore, we investigated the associations of the duration, type, intensity, and number of PAs one participates in pre- and post-diagnosis with mortality in Korean patients with cancer. METHODS: Among the participants aged 40-69 years recruited from the Health Examines study, those diagnosed with cancer after baseline (n = 7749) and within 10 years before baseline (n = 3008) were included in the analyses for pre- and post-diagnosis PA, respectively. Duration, intensity, type, and number of leisure-time physical activities participated in were assessed using questionnaires. The Cox proportional hazard model was used to characterize the association between PA and cancer-specific mortality, adjusting for demographics, behaviors, comorbidities, and cancer stage based on the Surveillance, Epidemiology, and End Results program. RESULTS: Pre-diagnosis, patients participating in vigorous-intensity activities (hazard ratio [HR]: 0.70, 95% confidence interval [CI]: 0.61-0.82), walking (HR: 0.85, 95% CI: 0.74-0.97), climbing (HR: 0.65, 95% CI: 0.55-0.77), sports (HR: 0.39, 95% CI: 0.25-0.61), and more than two activities (HR: 0.73, 95% CI: 0.63-0.86) had significantly lower all-cause mortality. Importantly, these associations were only found in patients with colorectal cancer participating in vigorous-intensity activities (HR: 0.40, 95% CI: 0.23-0.70). Post-diagnosis, only patients who performed more than two activities (HR: 0.65, 95% CI: 0.44-0.95) had significantly lower all-cause mortality. Similar associations were found for cancer mortality, both pre- and post-diagnosis. CONCLUSION: Specific characteristics of PA pre- and post-diagnosis may influence the survival of cancer patients.

Associations between Physical Activity and Incidence of Cancer among Overweight Adults in Korea: Results from the Health Examinees-G Study.

Although the protective effects of physical activity against several cancers are well established, evidence is inconsistent concerning Asian populations. Therefore, we assessed the association between the characteristics of physical activity and overall and type-specific cancer incidence in Koreans and examined the differences in association according to obesity status. Using prospective data from 112,108 participants in the Health Examinees study-G from 2004 to 2013, we evaluated the association between leisure-time physical activity (LTPA) and the incidence of overall and type-specific cancers using the Cox proportional hazards model. Self-reported LTPA participation, duration per week, intensity, type, and diversity were assessed. The incidence of overall and type-specific cancers, including colorectal, gastric, lung, breast, and prostate cancer and 13 obesity-related cancers, was identified using the Korea Central Cancer Registry from 1999 to 2018. Analyses were also stratified according to obesity status. In overweight males, participation in vigorous LTPA [HR, 0.84; 95% confidence interval (CI), 0.72-0.97] and walking (HR, 0.84; 95% CI, 0.72-0.98) were associated with a lower risk of cancer overall. Regarding cancer types, climbing was marginally associated with a lower risk of colorectal cancer in overweight males (HR, 0.61; 95% CI, 0.37-1.00). In normal-weight females, although there was an increased risk in those performing recreational activities, this risk was attenuated when those diagnosed with thyroid cancer were excluded. In the analysis for 13 obesity-related cancers, consistent associations were found. These findings suggest the need for greater public awareness regarding physical activity among overweight individuals within the Asian population. PREVENTION RELEVANCE: Overall cancer risk is associated with leisure-time physical activity such as duration, intensity, type, and diversity in overweight males, but not in the general population. The decreased risk was most noticeable for colorectal cancer. Our results suggest that physical activity may reduce the risk of cancer among overweight Asian males.

Dynamic changes in clinical biomarkers of cardiometabolic diseases by changes in exercise behavior, and network comparisons: a community-based prospective cohort study in Korea.

OBJECTIVES: Lifestyles, including exercise behaviors, change continually over time. This study examined whether the clinical biomarkers (CBs) related to cardiometabolic diseases (CMDs) and their relationships differed with changes in exercise behavior. METHODS: The Ansan-Ansung cohort study (third to fifth phases; n=2,668) was used in the current study. Regular exercise behavior was investigated using a yes/no questionnaire. Changes in exercise behavior were classified into 4 groups: Y-N, N-Y, Y-Y, and N-N, with "Y" indicating that a participant regularly engaged in exercise at a given time point and "N" indicating that he or she did not. Fourteen CBs related to CMDs were used, and the associations between changes in exercise behavior and relative changes in CBs were examined. CB networks were constructed and topological comparisons were conducted. RESULTS: Y-N was associated with increases in fasting blood sugar and insulin levels in men, and increased total cholesterol and low-density lipoprotein cholesterol levels in women. Meanwhile, N-Y was inversely associated with body fat percentage, visceral fat percentage, fasting insulin, and triglyceride level. Waist circumference played a central role in most networks. In men, more edges were found in the N-Y and Y-Y groups than in the N-N and Y-N groups, whereas women in the N-Y and Y-Y groups had more edges than those in the N-N and Y-N groups. CONCLUSIONS: Consistent exercise or starting to engage in regular exercise had favorable effects on CBs related to CMDs, although their network patterns differed between the sexes.

Stratifying the risk of ovarian cancer incidence by histologic subtypes in the Korean Epithelial Ovarian Cancer Study (Ko-EVE).

INTRODUCTION: This study aimed to verify the association between ovarian cancer (OC) and reproductive- and lifestyle-related risk factors stratified by the subtype of OC. METHODS: In this matched case-control study derived from the Korean epithelial ovarian cancer study (Ko-EVE), we calculated the risk of OC subtypes using odds ratios (ORs) and 95% confidence intervals (95% CIs) in a logistic regression model. RESULTS: As a result of matching, 531 cases and 2,124 controls were selected. Smoking had positive association with high-grade serous (HGS) OC (OR = 2.69, 95% CI = 1.15-6.30), whereas alcohol consumption had positive association with mucinous type (MUC) (OR = 3.63, 95% CI = 1.39-9.49). Obesity (≥30 kg/m2 ) was associated with clear cell type (CLC) (OR = 4.57, 95% CI = 1.06-19.77). Spontaneous abortion was negatively associated with CLC (OR = 0.34, 95% CI = 0.13-0.90), in contrast to HGS (OR = 1.43, 95% CI = 0.96-2.15). Tubal ligation, hysterectomy, and oophorectomy were associated with decreased risk of HGS (OR = 0.14, 95% CI = 0.05-0.39; OR = 0.23, 95% CI = 0.07-0.73; OR = 0.28, 95% CI = 0.08-0.97, respectively). Early menarche was strongly associated with increased risk of CLC, but not MUC (OR = 6.11, 95% CI = 1.53-24.42; OR = 3.23, 95% CI = 0.98-10.86). Further, childbirth (≥2 times) was negatively associated with endometrioid type OC and CLC (OR = 0.11, 95% CI = 0.04-0.35; OR = 0.12, 95% CI = 0.02-0.37, respectively). Oral contraceptives and hormone replacement therapy were negatively associated with OC (OR = 0.61, 95% CI = 0.40-0.93; OR = 0.51, 95% CI = 0.32-0.80, respectively), and similar negative associations were also observed in HGS (OR = 0.69; OR = 0.60, respectively). Associations between family history of breast cancer and OC, regular exercise (≥5/week), and artificial abortion and OC were similar across all subtypes (OR = 3.92; OR = 0.41; OR = 0.72, respectively). CONCLUSION: A heterogeneous association between some risk factors and the incidence of each subtype of epithelial OC was observed, suggesting that the carcinogenic mechanisms of each subtype may be partly different.

A time-dependent subdistribution hazard model for major dental treatment events in cancer patients: a nationwide cohort study.

BACKGROUND: Dental care in cancer patients tends to be less prioritized. However, limited research has focused on major dental treatment events in cancer patients after the diagnosis. This study aimed to examine dental treatment delays in cancer patients compared to the general population using a national claims database in South Korea. METHOD: The Korea National Health Insurance Service-National Sample Cohort version 2.0, collected from 2002 to 2015, was analyzed. Treatment events were considered for stomatitis, tooth loss, dental caries/pulp disease, and gingivitis/periodontal disease. For each considered event, time-dependent hazard ratios and associated 95% confidence intervals were calculated by applying a subdistribution hazard model with time-varying covariates. Mortality was treated as a competing event. Subgroup analyses were conducted by type of cancer. RESULTS: The time-dependent subdistribution hazard ratios (SHRs) of stomatitis treatment were greater than 1 in cancer patients in all time intervals, 2.04 within 30 days after cancer diagnosis, and gradually decreased to 1.15 after 5 years. The SHR for tooth loss was less than 0.70 within 3 months after cancer diagnosis and increased to 1 after 5 years. The trends in SHRs of treatment events for other dental diseases were similar to those observed for tooth loss. Subgroup analyses by cancer type suggested that probability of all dental treatment event occurrence was higher in head and neck cancer patients, particularly in the early phase after cancer diagnosis. CONCLUSION: Apart from treatments that are associated with cancer therapy, dental treatments in cancer patients are generally delayed and cancer patients tend to refrain from dental treatments. Consideration should be given to seeking more active and effective means for oral health promotion in cancer patients.

Associations Between Modifiable Risk Factors and Changes in Glycemic Status Among Individuals With Prediabetes.

OBJECTIVE: To examine the associations between modifiable risk factors and glycemic status changes in individuals with prediabetes. RESEARCH DESIGN AND METHODS: A total of 10,358 individuals with prediabetes defined by their fasting blood glucose and HbA1c levels from the Health Examinees-Gem study were included in the present study. Modifiable factors, including BMI, abdominal obesity, smoking status, physical activity, alcohol consumption, diet quality, hypertension, and dyslipidemia, were examined to determine their associations with changes in glycemic status during follow-up. In addition, modifiable-factor scores were calculated, and their association with changes in glycemic status was also analyzed. RESULTS: The median follow-up time for this study was 4 years (range, 1-7 years). BMI ≥25 kg/m2 (adjusted odds ratio [OR] 0.71 [95% CI 0.63-0.79]), abdominal obesity (OR 0.76 [95% CI 0.68-0.86]), heavy drinking (OR 0.74 [95% CI 0.60-0.91]), hypertension (OR 0.71 [95% CI 0.64-0.79]), and dyslipidemia (OR 0.78 [95% CI 0.70-0.85]) were associated with a lower possibility of normoglycemia reversion. BMI ≥25 kg/m2 (OR 1.58 [95% CI 1.29-1.94]), abdominal obesity (OR 1.31 [95% CI 1.11-1.55]), current smoking (OR 1.43 [95% CI 1.07-1.91]), and hypertension (OR 1.26 [95% CI 1.07-1.49]) were associated with a higher probability of type 2 diabetes progression. Having more favorable modifiable factors was also associated with normoglycemia reversion (OR 1.46 [95% CI 1.30-1.64]) and type 2 diabetes progression (OR 0.62 [95% CI 0.49-0.77]). CONCLUSIONS: More favorable modifiable factors were related to a higher probability of returning to normoglycemia and a lower probability of progression to type 2 diabetes.