Background: Given that the role of serum testosterone on incident cardiovascular disease has been uncertain, it is necessary to find out the relationship between serum testosterone and carotid atherosclerosis. Methods: The study participants included 1,302 Korean adults (873 men and 429 postmenopausal women) who participated in the Healthy Twin Study and were not receiving androgen deprivation therapy. The participants were classified into three groups: men aged <40 and ≥40 years and postmenopausal women. Total testosterone (TT) and sex hormone-binding globulin (SHBG) concentrations were measured using electrochemiluminescence immunoassays, and free testosterone (cFT) levels were calculated using Vermeulen’s method. Carotid intima-media thickness (IMT) was measured at three levels using a high-resolution B-mode ultrasound equipped with a 7-MHz linear transducer. The associations between sex hormone concentrations and carotid IMT were evaluated using a mixed linear regression analysis. Results: After adjusting for cardiovascular risk factors, TT was found to be inversely associated with common carotid IMT in men aged ≥40 years, with a 4.5% decrease in common carotid IMT for every one-standard deviation increase in TT concentration (P=0.0063). In contrast, TT was not significantly associated with carotid IMT in all segments in men aged <40 years and postmenopausal women. Additionally, SHBG and cFT were not associated with carotid IMT in any segment. Conclusion The significant association between TT level and common carotid IMT in men aged ≥40 years suggests that decreased testosterone levels are involved in the development of atherosclerosis in men.

Background: Previous studies have shown a close relationship between skipping breakfast and nutritional deficiency. However, the impact of regular eating, including lunch and dinner, has not been studied well. We explored the correlation between regularity and frequency of daily meals and nutritional status. Methods: We analyzed Korea National Health and Nutrition Examination Surveys between 2016 and 2018. A total of 7,725 adults aged 19–49 years were classified into four groups according to the regularity of meal intake: three-meal regular diet (3MRD), two-meal regular diet, one-meal regular diet, and irregular diet (IRD). Food and nutrient intake was assessed using the 24-hour recall method and estimated by a generalized linear model in complex sample weight variables. Results: In IRD, there were relatively more females who were not married, lived alone, or reported low levels of education. As subjects ate more meals, more people felt thinner and healthier by themselves. Dietary intake of cereal, vegetables, seaweed, and fiber was directly proportional to the number of regular meals as well as essential components such as water, carbohydrates, protein, fat, and micronutrients. Contrarily, alcohol and beverage consumption was inversely proportional to the number of regular meals. Intake level of legumes, fish, fruits, seasonings, milk, oils, sugars, and cholesterol was consistent regardless of meal frequency. Conclusion Our findings suggest that 3MRD showed nutrient adequacy and a healthier profile on body weight, body mass index, waist circumference, blood pressure, serum fasting glucose, total cholesterol, and triglyceride.

Background: We aimed to evaluate the association between metabolic syndrome (MetS) and hearing loss (HL) in light of noise exposure in Korean middle-aged adults. Methods: Subjects were 10,356 adults (4,509 males, 5,847 females) aged 40–80 years, who completed audiometric tests and laboratory examinations as part of the Korea National Health and Nutrition Examination Survey between 2010 and 2012. MetS was defined according to the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP III) and International Diabetes Federation (IDF). Low-frequency HL was defined as pure tone averages >25 decibels (dB) at low frequencies (0.5, 1, and 2 kilohertz [kHz]). High-frequency HL was defined as pure tone averages >25 dB at high frequencies (3, 4, and 6 kHz). Odd ratios (OR) and 95% confidence intervals (CI) of MetS associated with each HL type were estimated using multiple logistic regression analysis after adjusting for covariates and taking into consideration sampling weight. Results: 38.1% and 28.6% met the MetS by NCEP III and IDF criteria, respectively. Prevalence of HL was 29.3% and 63.9% for low- and high-frequency HL, respectively. MetS defined by NCEP III was associated with higher risk of high-frequency HL (OR, 1.35; 95% CI, 1.05–1.73), while MetS by IDF criteria was not. The interaction by the noise exposure on the MetS and high-frequency HL was not significant (P-interaction=0.100). There was no association between MetS and low-frequency HL, regardless of applied diagnostic criteria for MetS. Conclusion Our findings suggest MetS is associated with high-frequency HL in people with exposure to noise.

Background: As indoor activity increases with modern lifestyles changes, reduced exposure to sunlight may lead to reduced vitamin D synthesis. Previous studies demonstrated that increased vitamin D level is associated with decreased risk of colon cancer; therefore, this study attempted to determine the association between vitamin D and colon polyps, which may be precancerous lesions, in participants who underwent colonoscopy exams. Methods: A total of 31,004 participants who underwent routine health checkups, including vitamin D level and colonoscopy, at Samsung Medical Center in South Korea from 2010 to 2018 were included in the study. Colorectal polyps were diagnosed through biopsy after performing colonoscopy exams. Participants were categorized into three groups according to level of vitamin D (deficient: <20 ng/mL), insufficient: 20≤ vitamin D <30 ng/mL, and sufficient: ≥30 ng/mL). We analyzed the presence of colorectal polyps according to vitamin D level, and performed multiple logistic regression analyses for the association between vitamin D level and colorectal polyps. Results: About 50% of participants had colorectal polyps (hyperplastic polyp, n=4,864; adenomatous polyp, n=10,470; adenocarcinoma, n=24). There were no significant associations between vitamin D categories and colorectal polyp and colorectal cancer. However, when further analyzing by type of polyp, the risk of hyperplastic polyps significantly decreased with increasing vitamin D levels (P for trend=0.006). Conclusion We did not find evidence for an association between vitamin D and overall colorectal polyps; however, we observed a trend for decreased odds of hyperplastic polyps with increased vitamin D levels in comparison to vitamin D deficient subjects.

Background: We aimed to evaluate the association between metabolic syndrome (MetS) and hearing loss (HL) in light of noise exposure in Korean middle-aged adults. Methods: Subjects were 10,356 adults (4,509 males, 5,847 females) aged 40–80 years, who completed audiometric tests and laboratory examinations as part of the Korea National Health and Nutrition Examination Survey between 2010 and 2012. MetS was defined according to the National Cholesterol Education Program-Third Adult Treatment Panel (NCEP III) and International Diabetes Federation (IDF). Low-frequency HL was defined as pure tone averages >25 decibels (dB) at low frequencies (0.5, 1, and 2 kilohertz [kHz]). High-frequency HL was defined as pure tone averages >25 dB at high frequencies (3, 4, and 6 kHz). Odd ratios (OR) and 95% confidence intervals (CI) of MetS associated with each HL type were estimated using multiple logistic regression analysis after adjusting for covariates and taking into consideration sampling weight. Results: 38.1% and 28.6% met the MetS by NCEP III and IDF criteria, respectively. Prevalence of HL was 29.3% and 63.9% for low- and high-frequency HL, respectively. MetS defined by NCEP III was associated with higher risk of high-frequency HL (OR, 1.35; 95% CI, 1.05–1.73), while MetS by IDF criteria was not. The interaction by the noise exposure on the MetS and high-frequency HL was not significant (P-interaction=0.100). There was no association between MetS and low-frequency HL, regardless of applied diagnostic criteria for MetS. Conclusion Our findings suggest MetS is associated with high-frequency HL in people with exposure to noise.

Background: As indoor activity increases with modern lifestyles changes, reduced exposure to sunlight may lead to reduced vitamin D synthesis. Previous studies demonstrated that increased vitamin D level is associated with decreased risk of colon cancer; therefore, this study attempted to determine the association between vitamin D and colon polyps, which may be precancerous lesions, in participants who underwent colonoscopy exams. Methods: A total of 31,004 participants who underwent routine health checkups, including vitamin D level and colonoscopy, at Samsung Medical Center in South Korea from 2010 to 2018 were included in the study. Colorectal polyps were diagnosed through biopsy after performing colonoscopy exams. Participants were categorized into three groups according to level of vitamin D (deficient: <20 ng/mL), insufficient: 20≤ vitamin D <30 ng/mL, and sufficient: ≥30 ng/mL). We analyzed the presence of colorectal polyps according to vitamin D level, and performed multiple logistic regression analyses for the association between vitamin D level and colorectal polyps. Results: About 50% of participants had colorectal polyps (hyperplastic polyp, n=4,864; adenomatous polyp, n=10,470; adenocarcinoma, n=24). There were no significant associations between vitamin D categories and colorectal polyp and colorectal cancer. However, when further analyzing by type of polyp, the risk of hyperplastic polyps significantly decreased with increasing vitamin D levels (P for trend=0.006). Conclusion We did not find evidence for an association between vitamin D and overall colorectal polyps; however, we observed a trend for decreased odds of hyperplastic polyps with increased vitamin D levels in comparison to vitamin D deficient subjects.

OBJECTIVES: Emerging evidence indicates that sleep duration is associated with health outcomes. However, the relationship of sleep duration with long-term health is unclear. This study was designed to determine the relationship of sleep duration with mortality as a parameter for long-term health in a large prospective cohort study in Korea. METHODS: The study population included 13 164 participants aged over 20 years from the Korean Multi-center Cancer Cohort study. Information on sleep duration was obtained through a structured questionnaire interview. The hazard ratios (HRs) and 95% confidence intervals (CIs) for mortality were estimated using a Cox regression model. The non-linear relationship between sleep duration and mortality was examined non-parametrically using restricted cubic splines. RESULTS: The HRs for all-cause mortality showed a U-shape, with the lowest point at sleep duration of 7 to 8 hours. There was an increased risk of death among persons with sleep duration of < or =5 hours (HR, 1.21; 95% CI, 1.03 to 1.41) and of > or =10 hours (HR, 1.36; 95% CI, 1.07 to 1.72). In stratified analysis, this relationship of HR was seen in women and in participants aged > or =60 years. Risk of cardiovascular disease-specific mortality was associated with a sleep duration of < or =5 hours (HR, 1.40; 95% CI, 1.02 to 1.93). Risk of death from respiratory disease was associated with sleep duration at both extremes (< or =5 and > or =10 hours). CONCLUSIONS: Sleep durations of 7 to 8 hours may be recommended to the public for a general healthy lifestyle in Korea.
Adult ; Aged ; Body Mass Index ; Cardiovascular Diseases/mortality ; Cause of Death ; *Cohort Studies ; Female ; Humans ; Interviews as Topic ; Middle Aged ; Neoplasms/*mortality ; Proportional Hazards Models ; Prospective Studies ; Questionnaires ; Republic of Korea ; Respiratory Tract Diseases/mortality ; *Sleep ; Waist Circumference

Background: Prostate-specific antigen-based routine screening is not recommended for the general population due to conflicting results with mortality reduction. We aimed to develop a web-based decision aid (DA) for informed decision making for prostate cancer screening. Methods: Using the International Patient Decision Aid Standards (IPDAS) development process model, we developed our DA based on patient and clinician interviews and multidisciplinary expert discussions. The prototype consisted of predicting individual prostate cancer risk and informed decision-making, including knowledge, risk and benefit, cost, personal value, and decision making. We conducted a pilot study on 101 healthy men, evaluating the effectiveness of DA by measuring knowledge, attitude, and intention to screen before and after using the DA, as well as decisional conflict and usefulness after using the DA. Results: Of the 101 participants (median age 60 [50–69] years), 84% had not undergone screening for prostate cancer in the past two years. After using the DA, knowledge on prostate cancer screening increased (mean score [of 10] before versus after: 6.85 ± 1.03 versus 7.57 ± 1.25; P < 0.001), and intention to not screen increased from 27.7% to 51.5% (P < 0.001), but attitude toward screening did not change (P = 0.564). After use of the DA, 79 participants reported no decisional conflict, and the usefulness score was high (mean score [of 100] 77.35 ± 7.69), with 85% of participants reporting that the DA helped with decision making. Conclusion Our web-based DA yielded increased knowledge, decreased screening intention, and high perceived usefulness. These findings indicate potential clinical relevance, especially among younger individuals.

OBJECTIVES: Diabetes and obesity each increases mortality, but recent papers have shown that lean Asian persons were at greater risk for mortality than were obese persons. The objective of this study is to determine whether an interaction exists between body mass index (BMI) and diabetes, which can modify the risk of death by cardiovascular disease (CVD). METHODS: Subjects who were over 20 years of age, and who had information regarding BMI, past history of diabetes, and fasting blood glucose levels (n=16 048), were selected from the Korea Multi-center Cancer Cohort study participants. By 2008, a total of 1290 participants had died; 251 and 155 had died of CVD and stroke, respectively. The hazard for deaths was calculated with hazard ratio (HR) and 95% confidence interval (95% CI) by Cox proportional hazard model. RESULTS: Compared with the normal population, patients with diabetes were at higher risk for CVD and stroke deaths (HR, 1.84; 95% CI, 1.33 to 2.56; HR, 1.82; 95% CI, 1.20 to 2.76; respectively). Relative to subjects with no diabetes and normal BMI (21 to 22.9 kg/m2), lean subjects with diabetes (BMI <21 kg/m2) had a greater risk for CVD and stroke deaths (HR, 2.83; 95% CI, 1.57 to 5.09; HR, 3.27; 95% CI, 1.58 to 6.76; respectively), while obese subjects with diabetes (BMI > or =25 kg/m2) had no increased death risk (p-interaction <0.05). This pattern was consistent in sub-populations with no incidence of hypertension. CONCLUSIONS: This study suggests that diabetes in lean people is more critical to CVD deaths than it is in obese people.
Aged ; Blood Glucose/analysis ; *Body Mass Index ; Cardiovascular Diseases/etiology/*mortality ; Cohort Studies ; Diabetes Complications ; Diabetes Mellitus/*pathology ; Female ; Humans ; Male ; Middle Aged ; Proportional Hazards Models ; Risk Factors ; Stroke/etiology/mortality

Background: Data on the status of long-term follow-up (LTFU) care for childhood cancer survivors (CCSs) in Korea is lacking. This study was conducted to evaluate the current status of LTFU care for CCSs and relevant physicians’ perspectives. Methods: A nationwide online survey of pediatric hematologists/oncologists in the Republic of Korea was undertaken. Results: Overall, 47 of the 74 board-certified Korean pediatric hematologists/oncologists currently providing pediatric hematology/oncology care participated in the survey (response rate = 63.5%). Forty-five of the 47 respondents provided LTFU care for CCSs five years after the completion of primary cancer treatment. However, some of the 45 respondents provided LTFU care only for CCS with late complications or CCSs who requested LTFU care. Twenty of the 45 respondents oversaw LTFU care for adult CCSs, although pediatric hematologists/ oncologists experienced more difficulties managing adult CCSs. Many pediatric hematologists/oncologists did not perform the necessary screening test, although CCSs had risk factors for late complications, mostly because of insurance coverage issues and the lack of Korean LTFU guidelines. Regarding a desirable LTFU care system for CCSs in Korea, 27 of the 46 respondents (58.7%) answered that it is desirable to establish a multidisciplinary CCSs care system in which pediatric hematologists/oncologists and adult physicians cooperate. Conclusion The LTFU care system for CCS is underdeveloped in the Republic of Korea. It is urgent to establish an LTFU care system to meet the growing needs of Korean CCSs, which should include Korean CCSs care guidelines, provider education plans, the establishment of multidisciplinary care systems, and a supportive national healthcare policy.