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.

A kalihinol analog disrupts apicoplast function and vesicular trafficking in P. falciparum malaria

We report the discovery of MED6-189, an analog of the kalihinol family of isocyanoterpene natural products that is effective against drug-sensitive and drug-resistant Plasmodium falciparum strains, blocking both asexual replication and sexual differentiation. In vivo studies using a humanized mouse model of malaria confirm strong efficacy of the compound in animals with no apparent hemolytic activity or toxicity. Complementary chemical, molecular, and genomics analyses revealed that MED6-189 targets the parasite apicoplast and acts by inhibiting lipid biogenesis and cellular trafficking. Genetic analyses revealed that a mutation in PfSec13, which encodes a component of the parasite secretory machinery, reduced susceptibility to the drug. Its high potency, excellent therapeutic profile, and distinctive mode of action make MED6-189 an excellent addition to the antimalarial drug pipeline.

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.

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).

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 Potent Kalihinol Analogue Disrupts Apicoplast Function and Vesicular Trafficking in P. falciparum Malaria

Here we report the discovery of MED6-189, a new analogue of the kalihinol family of isocyanoterpene (ICT) natural products. MED6-189 is effective against drug-sensitive and -resistant P. falciparum strains blocking both intraerythrocytic asexual replication and sexual differentiation. This compound was also effective against P. knowlesi and P. cynomolgi. In vivo efficacy studies using a humanized mouse model of malaria confirms strong efficacy of the compound in animals with no apparent hemolytic activity or apparent toxicity. Complementary chemical biology, molecular biology, genomics and cell biological analyses revealed that MED6-189 primarily targets the parasite apicoplast and acts by inhibiting lipid biogenesis and cellular trafficking. Genetic analyses in P. falciparum revealed that a mutation in PfSec13, which encodes a component of the parasite secretory machinery, reduced susceptibility to the drug. The high potency of MED6-189 in vitro and in vivo, its broad range of efficacy, excellent therapeutic profile, and unique mode of action make it an excellent addition to the antimalarial drug pipeline.

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.

Association of body mass index and bloodstream infections in patients on extracorporeal membrane oxygenation: a single-centre, retrospective, cohort study

BACKGROUND

Obesity is associated with poor clinical outcomes in critically ill patients. However, under some clinical conditions, obesity has protective effects. Bloodstream infections (BSI) are among the most common nosocomial infections associated with extracorporeal membrane oxygenation (ECMO). BSI during ECMO is associated with higher mortality rates and poorer clinical outcomes.

AIM

To analyse whether body mass index (BMI) is associated with BSI during ECMO or with in-hospital mortality.

METHODS

All adult patients who had received ECMO support for >48 h were included in the analysis. The analysis of total duration of ECMO support, in-hospital mortality and BSI was stratified by BMI category. The Cox proportional hazards model was used to compare the risk of BSI among BMI categories.

FINDINGS

In total, 473 patients were enrolled in the study. The average age was 56.5 years and 65.3% were men. The total duration of ECMO was approximately 11.8 days, with a mortality rate of 47.1%. The incidence rates of BSI and candidaemia were 20.5% and 5.5%, respectively. The underweight group required ECMO for respiratory support, whereas the overweight and obese groups required ECMO for cardiogenic support (P<0.0001). No significant difference in BSI rate was found (P=0.784). However, after adjusting for clinical factors, patients in Group 4 (BMI 25.0-<30.0 kg/m2) exhibited lower mortality compared with patients in Group 2 (normal BMI) (P=0.004).

CONCLUSION

BMI was not associated with risk of BSI, but patients with higher BMI showed lower in-hospital mortality associated with ECMO support.

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.

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.

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.

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.

Potential overestimation of cognitive impairment because of hearing loss: impact of test modalities on cognitive test scores

OBJECTIVE

Hearing impairment in older adults may affect cognitive function and increase the risk of dementia. Most cognitive tests are delivered auditorily, and individuals with hearing loss may fail to hear verbal instructions. Greater listening difficulty and fatigue in acoustic conditions may impact test performance. This study aimed to examine the effect of decreased audibility on cognitive screening test performance in older adults.

METHOD

Older adults (n = 63) with different levels of hearing loss completed a standard auditory Mini-Mental State Examination test and a written version of the test.

RESULTS

Individuals with moderate to moderately severe hearing loss (41-70 dB) performed significantly better on the written (24.34 ± 4.90) than on the standard test (22.55 ± 6.25), whereas scores were not impacted for mild hearing loss (less than 40 dB).

CONCLUSION

Hearing evaluations should be included in cognitive assessment, and test performance should be carefully interpreted in individuals with hearing loss to avoid overestimating cognitive decline.

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 (hazard ratio [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.

Impact of tuberculosis on the incidence of osteoporosis and osteoporotic fractures: a nationwide population-based cohort study

OBJECTIVES

Despite the high prevalence of tuberculosis (TB) and the disease burden of osteoporosis and osteoporotic fractures, there is still a lack of well-designed, large-scale studies demonstrating associations among them. We aimed to investigate the effect of TB on the incidence of osteoporosis and osteoporotic fractures.

STUDY DESIGN

This was a nationwide population-based cohort study.

METHODS

This study was conducted using the National Health Insurance Service Database of South Korea. We included patients with newly diagnosed TB aged >40 years from January 2006 to December 2017. An uninfected control for each TB patient was randomly extracted by frequency matching for sex, age, income level, residence, and registration date at a 2:1 ratio. The primary outcome was the incidence of osteoporosis and osteoporotic fractures between the two groups, adjusted for sex, age, income level, residence, comorbidities, body mass index, blood pressure, laboratory tests, alcohol drinking, and smoking. The risk factors associated with osteoporosis or osteoporotic fractures were also investigated.

RESULTS

A total of 164,389 patients with TB and 328,778 matched controls were included (71.9% males). The mean duration of follow-up was 7.00 ± 3.49 years. The incidence of osteoporosis in patients with TB was 6.1 cases per 1000 person-years, which was significantly higher than that in matched controls (adjusted hazard ratio [aHR] 1.349, 95% confidence interval [CI] 1.302-1.398, P < 0.001). The incidence of osteoporotic fractures was also higher in patients with TB than in controls (aHR 1.392, 95% CI 1.357-1.428, P < 0.001). Among fractures, the risk of hip fracture was the highest (aHR 1.703, 95% CI 1.612-1.798, P < 0.001).

CONCLUSIONS

TB independently contributes to the incidence of osteoporosis and osteoporotic fractures, particularly hip fractures.

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.

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

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.

Conclusion

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.

Aggregation tests identify new gene associations with breast cancer in populations with diverse ancestry

BACKGROUND

Low-frequency variants play an important role in breast cancer (BC) susceptibility. Gene-based methods can increase power by combining multiple variants in the same gene and help identify target genes.

METHODS

We evaluated the potential of gene-based aggregation in the Breast Cancer Association Consortium cohorts including 83,471 cases and 59,199 controls. Low-frequency variants were aggregated for individual genes' coding and regulatory regions. Association results in European ancestry samples were compared to single-marker association results in the same cohort. Gene-based associations were also combined in meta-analysis across individuals with European, Asian, African, and Latin American and Hispanic ancestry.

RESULTS

In European ancestry samples, 14 genes were significantly associated (q < 0.05) with BC. Of those, two genes, FMNL3 (P = 6.11 × 10-6) and AC058822.1 (P = 1.47 × 10-4), represent new associations. High FMNL3 expression has previously been linked to poor prognosis in several other cancers. Meta-analysis of samples with diverse ancestry discovered further associations including established candidate genes ESR1 and CBLB. Furthermore, literature review and database query found further support for a biologically plausible link with cancer for genes CBLB, FMNL3, FGFR2, LSP1, MAP3K1, and SRGAP2C.

CONCLUSIONS

Using extended gene-based aggregation tests including coding and regulatory variation, we report identification of plausible target genes for previously identified single-marker associations with BC as well as the discovery of novel genes implicated in BC development. Including multi ancestral cohorts in this study enabled the identification of otherwise missed disease associations as ESR1 (P = 1.31 × 10-5), demonstrating the importance of diversifying study cohorts.