Previous systematic reviews and meta-analyses of randomized controlled trials have reported controversial findings regarding the effects of melatonin on pain reduction. The aim of this study was to evaluate the efficacy of melatonin on pain among adults using a meta-analysis of randomized, double-blind, placebo-controlled trials (RDBPCTs). PubMed, EMBASE, the Cochrane Library, and the bibliographies of relevant articles were searched up to February 2020. Two of the authors independently evaluated eligibility of the studies based on the pre-determined criteria and extracted data. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) for the pain score change were calculated using a random-effects meta-analysis. Out of 463 that met the initial criteria, a total of 30 trials, which involved 1967 participants with 983 in an intervention group and 984 in a control group, were included in the final analysis. In a random-effects meta-analysis, the use of melatonin reduced chronic pain in all the trials (5 studies, SMD −0.65, 95% CI −0.96 to −0.34, I² = 57.2%) and high-quality trials (4 studies, SMD −0.62, 95% CI −1.01 to −0.23, I² = 49.3%). Moreover, the use of melatonin significantly reduced acute postoperative pain (11 studies, SMD −0.82, 95% CI −1.40 to −0.25, I² = 93.0%). However, the subgroup meta-analysis of high-quality RDBPCTs showed no significant association between them (6 studies, SMD −0.21, 95 % CI −0.66 to 0.24, I² = 82.4%). The current study suggests that melatonin might be used in treatment of chronic pain, while there is no sufficient evidence for acute postoperative or procedural pain. Further trials are warranted to confirm its analgesic effect.

The definition of sarcopenia focuses on muscle mass and function. Sarcopenic obesity is the relative excess of fat tissue with decreased muscle mass. We examined the association between cigarette smoking and sarcopenia according to obesity in middle-aged and elderly Koreans. We conducted a cross-sectional study of 9,385 subjects (age ≥50 years) based on data from the fourth and fifth Korea National Health and Nutrition Examination Surveys (2008-2011). Smoking groups were categorized by smoking status and the number of cigarettes smoked daily. Sarcopenia was defined as weight-adjusted appendicular skeletal muscle mass of 2 standard deviations below the sex-specific mean for young adults. Obesity was defined as fat mass ≥30% for men and ≥40% for women. Subjects were categorized into three groups: sarcopenic obese (SO), sarcopenic non-obese (SNO), and normal. Multiple logistic regression analysis was performed to assess the association between smoking and SNO and SO. Among men, current smokers were more associated with SNO than never-smokers (adjusted odds ratio [OR], 3.34; 95% confidence interval [CI], 1.09-10.26). However, there was no significant association between smoking status and SNO in women or SO in either sex. Among current smokers, moderate smokers (11-20 cigarettes/d) were more likely to be SNO (adjusted OR, 5.81; 95% CI, 1.12-30.31) and heavy smokers (>20 cigarettes/d) were more likely to be SO (adjusted OR, 9.53; 95% CI, 1.65-55.01) than light smokers (<11 cigarettes/d). In men, smoking was positively associated with SNO, and heavy smokers were more likely to be SO than light smokers.

Background: This study aimed to determine the link between water consumption and abdominal obesity in individuals aged 19 years and above, utilizing a sample from the 8th Korea National Health and Nutrition Examination Survey.Methods: Participants were divided into two groups based on their water intake: those meeting adequate intake (≥5 cups for men and ≥4 cups for women) and those with inadequate intake (<5 cups for men and <4 cups for women). Multivariate logistic regression analysis was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs), adjusted for potential confounders.Results: Compared with the inadequate water intake group, the adequate water intake group showed a lower adjusted OR for abdominal obesity (adjusted OR, 0.874; 95% CI, 0.770–0.992). In the subgroup analysis, the adjusted OR for abdominal obesity in the 19–39 age group was 0.712 (95% CI, 0.520–0.974). However, no significant association was observed in the 40–64 and 65 or higher age groups.Conclusion: Our findings indicate that sufficient water consumption may be negatively associated with abdominal obesity in adults, particularly among young adults; however, this association may not extend to older age groups.

Although prior studies showed the association between the amount of alcohol ingestion and the risk of depression and suicide, there has been a lack of research considering changes in alcohol intake over time. This research aimed to assess the associations of alcohol consumption level changes and the risk of depression and suicide among initial nondrinkers. Using data from the National Health Insurance Service in South Korea between 2002 and 2019, a total of 129,446 subjects were included and monitored from January 1, 2011, to December 31, 2019, of which 102,721 were never drinkers and 26,725 were former drinkers. For depression, the follow‐up periods ranged from 0.01 to 9.00 years (mean 8.65, median 9.00 years). Moreover, for suicide, the follow‐up periods ranged from 0.03 to 9.00 years (mean 8.99, median 9.00 years). To ensure robust results, the model was adjusted for several confounders in three steps: Model 1 was adjusted for sociodemographic factors (age and sex), Model 2 included additional lifestyle factors (household income, smoking status, and physical activity) in addition to Model 1 variables, and Model 3 included all variables from Model 2 and incorporated further variables including body mass index (BMI), systolic blood pressure, fasting serum glucose, total cholesterol, and the Charlson Comorbidity Index (CCI). The Cox proportional hazard regression was utilized to estimate the adjusted hazard ratio (aHR) and 95% confidence intervals (CIs) for depression and suicide risk after an increase in alcohol consumption. Individuals who increased alcohol consumption lightly up to one glass per day had a reduced risk of depression (aHR, 0.91; 95% CI, 0.84–0.98) compared with individuals who maintained their nondrinking status at the third medical checkup. Notably, stratified analyses indicated that the associations were only evident in those younger than 60 years and those physically active. Additionally, among former drinkers, those who increased their alcohol intake to four or more glasses per day had an increased risk of depression (aHR, 1.31; 95% CI, 1.04–1.66). However, individuals who initiated drinking between two and four glasses of alcoholic beverages per day were found to have a higher risk of suicide (aHR, 2.25; 95% CI, 1.31–3.87) relative to those who continued to abstain from drinking. Our findings suggest that small increases in alcohol intake among the initial nondrinkers are associated with a reduced risk of depression, whereas moderate‐to‐heavy increments in alcohol consumption are associated with a detrimental risk of suicide. This study has several limitations including the low number of suicide events, reliance on self‐reported alcohol consumption which may introduce underreporting bias, and the exclusion of important confounding variables such as educational attainment and dietary factors. Furthermore, the study population was exclusively Korean, limiting the generalizability of the findings to other ethnic groups.

Metabolic dysfunction-associated steatotic liver disease (MASLD) is distinguished by the buildup of excessive liver fat unrelated to alcohol consumption. However, the role of alcohol consumption on disease progression is debatable. Recently, alcohol flushing syndrome in Asian populations has gained interest, and its role in the risk of developing MASLD is unknown. Therefore, in this cross-sectional study, we investigated the association between alcohol consumption and MASLD in Korean men, considering their alcohol flushing response and utilizing the lipid accumulation product (LAP) score. Data from the Korean National Health and Nutrition Examination Survey (2019–2021) were analyzed. Participants were categorized into non-or-infrequent drinkers and light-to-heavy drinkers and further sub-classified based on alcohol flushing response as non-flushers and flushers. Multivariate logistic regression analysis showed a significant association between alcohol consumption and MASLD risk in both non-flushers (aHR 1.90, 95% CI 1.51–2.40, p < 0.001) and flushers (aHR 2.35, 95% CI 1.94–2.84, p < 0.001) after adjusting for potential confounding factors such as age, exercise, smoking, body mass index, systolic blood pressure, total cholesterol, and fasting plasma glucose. There was a significant interaction between alcohol consumption and alcohol flushing response for MASLD risk (p for interaction < 0.001). These findings emphasize the importance of alcohol flushing as a potential indicator of MASLD risk in Korean men and highlight the need for further research to understand the underlying mechanisms and develop targeted preventive strategies.

Artificial intelligence (AI) shows promise in improving the accuracy and efficiency of lung cancer screening, but its economic value remains uncertain. We developed a decision-analytic model combining a decision tree and Markov model to evaluate five screening strategies in South Korea: no screening, chest X-ray (CXR), AI-assisted CXR, low-dose computed tomography (LDCT), and AI-assisted LDCT. We simulated hypothetical cohorts of 10,000 individuals, stratified by age group and smoking status to reflect the Korean population distribution, and projected their lifetime costs and quality-adjusted life years (QALYs). Analyses applied a 4.5% discount rate and a willingness-to-pay (WTP) threshold of $32,409.9 per QALY. AI-assisted CXR produced incremental cost-effectiveness ratio (ICER) of $8679–$10,030 per QALY, demonstrating cost-effectiveness across all age groups. CXR alone was less favorable, and LDCT-based strategies exceeded the willingness-to-pay (WTP) threshold. These findings suggest AI-assisted CXR offers a scalable, economically viable strategy for lung cancer screening, supporting its integration into national programs.