Background
This study examined disparities in 1-year mortality rates between infants born to married and unmarried single-parent families, emphasizing the need for targeted health policies.
Methods
Data from 3,298,263 cases, obtained from the South Korea National Statistical Office (2010–2017), were analyzed. T-tests and chi-square tests were used to assess the demographic characteristics of the study group. The number of deaths per 1,000 live births was calculated, and logistic and multivariable logistic regressions were employed to compare infant mortality rates between family types. Additional stratified analyses, based on gestational age and birth weight, further elucidated the relationship between parental marital status and infant mortality.
Results
Infants from unmarried families exhibited a 3.34-fold higher crude odds ratio (OR) for 1-year mortality (95% confidence interval [CI], 2.56–4.36; P<0.001) than that from married families. After adjusting for confounders, the adjusted OR was 1.40 (95% CI, 1.03–1.92). Stratification by gestational age and birth weight revealed crude ORs of 4.62 (95% CI, 3.34– 6.39) in non-preterm infants (≥37 weeks) and 4.76 (95% CI, 3.46–6.56) in non-low-birth-weight infants (≥2.5 kg), highlighting a more pronounced disparity in infants born at or above normal weight and full term. No significant difference (P>0.05) was found in the crude OR for 1-year mortality rates among low-birth-weight (<2.5 kg) or preterm (<37 weeks) infants between the two-family types.
Conclusion
This study highlights the significant disparity in infant mortality rates based on parental marital status, underscoring the need for enhanced social support and tailored policies for unmarried single-parent families.

Semaglutide, a medication used for type 2 diabetes and weight loss, may have unexpected side effects such as sarcopenia and age-related loss of muscle mass and strength. A 74-year-old male patient with type 2 diabetes and dyslipidemia presented with progressive fatigue over 2 years. He experienced a significant decline in walking endurance and speed despite the absence of joint pain or other obvious causes. He had a history of ocular myasthenia gravis and localized prostate cancer, both of which were well-managed. Further investigation revealed a weight loss of 8 kg after starting semaglutide treatment for diabetes. Physical examinations revealed reduced muscle bulk and strength. Extensive investigations, including blood tests, imaging, and cardiopulmonary exercise testing, have ruled out other potential causes of fatigue. The patient’s fatigue improved after reducing the semaglutide dose and implementing a tailored exercise program that focused on muscle strengthening. This case highlights the potential contribution of semaglutide to muscle mass loss and subsequent fatigue, particularly among older adults.

Chiari malformation type I (CMI) is a structural abnormality characterized by cerebellar tonsil herniation through the foramen magnum, often leading to disrupted cerebrospinal fluid dynamics and syringomyelia. While CMI commonly presents with occipital headaches and neck pain, atypical manifestations, such as bilateral foot drops, are exceedingly rare. We describe a 37-year-old female patient presenting with bilateral foot drop, which was later established to be caused by syringomyelia secondary to CMI. Magnetic resonance imaging revealed an 8 mm tonsillar descent and a syrinx extending to the conus medullaris. The patient refused surgical intervention and opted for conservative management; partial functional recovery was subsequently observed. This report emphasizes the importance of recognizing rare neurological presentations of CMI. To our knowledge, this is the first documented case of CMI with syringomyelia presenting as a bilateral foot drop.

Background
The association between sleep duration and obesity risk among risky drinkers remains controversial. This study aims to investigate the relationship between adequate sleep duration and both central and overall obesity among risky drinkers in Korea, with a focus on identifying potential interventions to reduce obesity rates.
Methods
We analyzed data from 978 individuals, selected from 1,356 risky drinkers—as defined by the World Health Organization criteria—who participated in the 2019–2020 Korea National Health and Nutrition Examination Survey. Participants had no missing values and were engaged in economic activities. Demographic characteristics and key variables by obesity status were examined using frequency analysis and chi-square tests. Multivariable logistic regression analysis was performed to explore the association between sleep duration and obesity. To account for the stratified sampling design, we utilized complex sample analysis with weighted values.
Results
Risky drinkers with adequate sleep duration (7–9 hours) were less likely to be obese based on waist circumference (≥90 cm in males; ≥85 cm in females) (odds ratio [OR], 0.64; 95% confidence interval [CI], 0.48–0.86) and body mass index (≥25 kg/m²) (OR, 0.56; 95% CI, 0.41–0.76). Trend analysis revealed a significant inverse relationship between sleep duration and obesity likelihood (P for trend <0.05). Gender-stratified analysis demonstrated that the association was significant among males and more pronounced in risky drinkers compared to the general population.
Conclusion
This study suggests that adequate sleep duration may play a key role in reducing obesity rates among Korean male risky drinkers. Further longitudinal studies are recommended to strengthen this finding.

Ketone bodies produced by sodium-glucose cotransporter 2 (SGLT2) inhibitors can be advantageous, providing an efficient and stable energy source for the brain and muscles. However, in patients with diabetes, ketogenesis induced by SGLT2 inhibitors may be harmful, potentially resulting in severe diabetic ketoacidosis (DKA). During fasting, ketone body production serves as an alternative and efficient energy source for the brain by utilizing stored fat, promoting mental clarity, and reducing dependence on glucose. The concurrent use of SGLT2 inhibitors during perioperative fasting may further elevate the risk of euglycemic DKA. We describe a case of DKA that occurred during perioperative fasting in a patient receiving empagliflozin, an SGLT2 inhibitor. This case underscores the importance of recognizing the potential risk of DKA in patients with diabetes using SGLT2 inhibitors during perioperative fasting.

Background
Although breakfast provides essential nutrients and energy, skipping this meal has become increasingly common among young adults in Korea. In this study, we examine the relationship between breakfast consumption and body composition.
Methods
We analyzed data from 17,763 students aged 18–39 at Seoul National University (2018–2022). Participants were categorized based on their breakfast frequency: non-skippers, 1 to 3-day skippers, and 4 to 7-day skippers. Measurements included body mass index, waist circumference, body fat percentage, fat mass index (FMI), fat-free mass index (FFMI), and skeletal muscle mass index (SMI). Multivariable logistic and linear regression models adjusted for age, sex, alcohol use, smoking, physical activity, sleep, and food consumption frequencies were used.
Results
Obesity (17.4% vs. 14.8%) and abdominal obesity (10.0% vs. 7.8%) were higher in those skipping breakfast 4 to 7 d/wk compared with non-skippers. Skipping breakfast was not significantly associated with abdominal obesity in either sex. In women, the odds of obesity were higher (odds ratio, 1.57; 95% confidence interval, 1.14–2.15; P=0.006), whereas no significant difference was observed in men. Men who skipped breakfast had increased body fat percentage (coefficient, 0.87; P<0.001) and FMI (coefficient, 0.18; P=0.009) and decreased FFMI and SMI. Women showed increased body fat percentage (coefficient, 0.92; P<0.001) and FMI but no significant differences in FFMI or SMI.
Conclusion
Skipping breakfast adversely affects body composition by increasing body fat percentage and FMI. Further research is needed to confirm these findings and explore the underlying mechanisms.

Background
Insulin resistance (IR) influences lipid metabolism, particularly small dense low-density lipoprotein cholesterol (sdLDL-C), a key feature of diabetic dyslipidemia and a predictor of cardiovascular disease. The single-point insulin sensitivity estimator (SPISE) index is an effective tool for assessing IR. This study explored the relationship between the SPISE index and average low-density lipoprotein cholesterol (LDL-C) particle size in obese Korean adults.
Methods
Cardiovascular risk was assessed in 161 obese individuals. The participants were divided into three groups based on SPISE index tertiles. Steiger’s Z test was used to assess the differences in correlation coefficients among various IR indices and average LDL-C particle size. Multivariate linear regression models were used to determine the independent association between the SPISE index and average LDL-C particle size. Receiver operating characteristic (ROC) curves established the SPISE index cut-off for sdLDL-C particle dominance.
Results
The SPISE index was positively correlated with mean LDL-C particle size after adjusting for confounders. It demonstrated a stronger independent association with average LDL-C particle size (r=0.679, P<0.001) than with fasting insulin, the homeostatic model assessment for IR, and the quantitative insulin sensitivity check index (P<0.001 for all). ROC analysis identified an optimal SPISE index cutoff for sdLDL-C predominance of 4.955, with an area under the curve of 0.745.
Conclusion
Our findings indicate a direct correlation between the SPISE index and average LDL-C particle size, suggesting that the SPISE index may complement labor-intensive IR indices and sdLDL-C measurement techniques for estimating IR-induced sdLDL-C predominance.

Background
Depression is a prevalent mental health disorder that presents substantial public health challenges. Emerging evidence underscores the role of dietary patterns in mitigating depressive symptoms. This study investigated the association between diet quality, assessed using the Recommended Food Score (RFS), and depressive symptoms, evaluated with the Patient Health Questionnaire-9 (PHQ-9), in a sample of Korean adults.
Methods
This cross-sectional study analyzed data from 19,786 participants recruited from a general hospital in Korea, all of whom completed the RFS and PHQ-9 assessments. General characteristics and anthropometric indices were recorded. Statistical analyses included chi-square tests and binary logistic regression to calculate odds ratios (ORs) and 95% confidence intervals for depressive symptoms according to RFS scores, adjusting for potential confounders.
Results
Higher RFS scores were associated with reduced odds of depression in univariate (OR, 0.59; P<0.001) and multivariate (OR, 0.72; P<0.001) analyses. Sociodemographic factors, including older age, higher education, marital status, higher income, professional occupation, and regular exercise, were linked to decreased odds of depression. Conversely, female sex, current smoking, and alcohol consumption were associated with increased odds.
Conclusion
The findings reveal an inverse relationship between diet quality and depressive symptoms among Korean adults, emphasizing the potential of dietary improvements in mental health promotion. Sociodemographic factors significantly influence depression risk. Future studies should adopt longitudinal designs incorporating a wider range of variables to elucidate these complex interactions.

Background
Menstrual hygiene is crucial to a woman’s physical, social, and mental well-being. The menstrual cup offers a safe and effective solution but still requires wider adoption. This study aims to assess awareness, practices, and barriers regarding the use of menstrual cups among women of reproductive age.
Methods
A cross-sectional study was conducted among 246 participants, randomly selected from outpatient settings of a tertiary care hospital in 2022. Non-pregnant menstruating women were included, while those with pelvic infections or cognitive impairments were excluded. After explaining the study’s purpose and ensuring anonymity, data were collected using a structured questionnaire adapted from previous studies conducted in India and abroad. Knowledge and practices were depicted using descriptive statistics, while factors affecting awareness were analyzed using a multivariable binary logistic regression analysis approach.
Results
Approximately 64.2% of participants were aware of menstrual cups, but only three were users. Participants living in urban areas, practicing Hinduism, and marrying after the age of 20 years showed higher awareness. Users rated the cup as comfortable, with no skin irritation, foul odor, or dryness. The primary barrier to use was insufficient knowledge.
Conclusion
There is a gap in awareness and usage of menstrual cups, especially in low- and middle-income countries like India. Preliminary feedback from users is encouraging, suggesting that menstrual cups could offer a cost-effective, eco-friendly, and sustainable way to improve menstrual hygiene.

Background
The use of heated tobacco products (HTPs) among Korean adults has been steadily increasing since they were first introduced in 2017. It is known that smoking combustible cigarettes (CCs) adversely affects the serum lipid profile and increases the risk of cardiovascular disease. However, the health impacts of HTPs remain under- researched. This study, therefore, aims to explore the effects of HTP use on serum lipid levels.
Methods
This study involved 10,309 participants, selected from the Korea National Health and Nutrition Examination Survey VII-1 and VIII conducted between 2018 and 2021. Participants were categorized based on their smoking status: “HTPs ever user” included dual, triple, and past HTP users; “current HTPs only user” for those exclusively using HTPs; “current CCs only user” for those exclusively smoking CCs; and “never smoker.” Logistic regression analysis was used to assess the impact of smoking type on serum lipid concentrations.
Results
The analysis revealed that the “HTPs ever user” group had a higher odds ratio (OR) for elevated total cholesterol compared to the “never smoker” group (OR, 1.40; 95% confidence interval [CI], 1.03–1.92). The likelihood of having high low-density lipoprotein (LDL)-cholesterol was greatest in the “current HTPs only user” group when compared to “never smokers” (OR, 1.71; 95% CI, 1.01–2.89).
Conclusion
The findings indicate that exclusive use of HTPs is linked to an increased level of serum LDL-cholesterol. Further longitudinal studies are necessary to fully determine the health risks associated with HTPs.

Background
Updated reports on the population-based analysis of atopic dermatitis (AD) in Korea are rare. This study aimed to investigate the nationwide prevalence and systemic medication prescription trends of AD in Korea.
Methods
Based on the Korean National Health Insurance database, the prevalence of AD and systemic medication prescription trends in patients with AD were analyzed according to age groups and regional districts from 2010 to 2015.
Results
The prevalence of AD was the highest among patients aged 0–1 year (18.6%–24.5%), decreasing rapidly with increasing age (<2% in patients aged ≥20 years). From 2010 to 2015, the prevalence of AD decreased in children but increased slightly in adolescents and adults. In 2015, the proportion of systemic steroid prescriptions increased from 11.2% in the 0–9 years age group to 41.1% in the 50–59 years age group, while that of systemic antibiotic prescriptions gradually decreased from 6.2% in the 0–9 years age group to 1.8% in the 80–89 years age group. The proportion of systemic steroid prescriptions by region remained consistently high in Gyeongbuk (34.2%– 34.9%) and low in Daejeon (20.2%–22.5%). The annual proportion of systemic cyclosporine prescriptions increased significantly from 0.6% in 2010 to 1.2% in 2015, with the highest rates observed in patients in their 30s (1.5%–2.4%), followed by those in their 20s (1.3%–2.3%) and 40s (1.1%–2.0%).
Conclusion
From 2010 to 2015, the prevalence of AD decreased in children but increased slightly in adolescents and adults. Approximately one-fourth of the patients with AD were prescribed systemic steroids, and the percentage of cyclosporine prescriptions doubled during the study period.

Background
Osteoporosis and hearing impairment are known to be associated, but specific data regarding gender, bone mineral density (BMD) measurement sites, and hearing frequency ranges remain unclear. This study aimed to clarify the relationship between hearing loss and BMD in adults over the age of 50. Additionally, the study sought to determine the frequency ranges of pure tone audiometry (PTA) related to osteoporosis, identify BMD measurement sites, and investigate gender differences.
Methods
A total of 1,523 adults (651 men and 872 women) over the age of 50, who participated in a medical health check-up at a university hospital, were included. PTA was conducted to assess hearing, and BMD was measured using dual-energy X-ray absorptiometry at the lumbar vertebrae (LV) and femur.
Results
In women over the age of 50, a significant association was observed between hearing impairment and osteoporosis (P<0.01), but no such association was found in men. Lumbar BMD (L1–4) in women was significantly associated with hearing loss at 4,000 and 8,000 Hz (both P<0.05), whereas femoral neck and total femur BMD showed no significant relationship. In multiple logistic regression analysis, the odds ratio (OR) between osteoporosis and hearing threshold at 4,000 Hz (OR, 2.078; 95% confidence interval [CI], 1.092–3.954) and 8,000 Hz (OR, 2.648; 95% CI, 1.543–4.544) remained statistically significant in women after adjusting for age and other risk factors.
Conclusion
In women over the age of 50, low BMD at the LV is significantly associated with hearing impairment, particularly at the high frequencies of 4,000 and 8,000 Hz.

Background
The use of e-cigarettes is increasing globally, particularly among young adults. Although several use them to quit smoking, their effects are controversial. The Fagerstrom Test for Nicotine Dependence (FTND) was used to assess nicotine dependence in the smoking cessation process. This study examined changes in FTND scores among young adults using different types of cigarettes over a 1-year period.
Methods
Prospective cohort data were collected from cigarette users at higher education institutions in the lower northern region of Thailand to analyze changes in FTND scores over a 1-year period. E-cigarette users and combined users were compared with conventional cigarette users. A marginal structural model (MSM) with an inverse probability of weighting (IPW) was used to adjust for time-dependent and time-independent confounders.
Results
Of the 133 participants, 58 were e-cigarette users (43.6%), 33 were combined cigarette users (24.8%), and 42 were conventional cigarette users (31.6%). The results revealed that when both time-dependent and time-independent confounders were adjusted using MSM with IPW, e-cigarette users had a 0.20 decrease in the mean FTND score, and combined users had a 0.47 decrease in the mean FTND score compared to conventional cigarette users. However, the difference was not statistically significant.
Conclusion
The use of e-cigarettes or combined cigarettes did not significantly affect nicotine dependence levels in young adults over a 1-year period. Consequently, e-cigarettes should not be recommended to reduce nicotine dependence among young adult cigarette users. Further studies are required to determine whether e-cigarettes affect smoking cessation rates.

Background
Gestational diabetes can lead to complications in pregnant women and neonates. Maternal glycated albumin levels during late pregnancy may help predict complications in both mothers and neonates.
Methods
This study was conducted in 120 singleton pregnant women diagnosed with gestational diabetes who visited Trinium Woman’s Hostipal between July 1, 2020, and June 30, 2022. In this study, the patients’ medical records were retrospectively analyzed. Gestational diabetes was diagnosed using a two-step testing method, and glycated albumin tests were performed during the third trimester of pregnancy. The optimal cutoff value of glycated albumin for predicting maternal complications during pregnancy and neonatal complications was determined using the receiver operating characteristic curve.
Results
A total of 45 patients developed maternal complications, with cesarean section (39 patients) due to fetal cephalopelvic disproportion being the most common. As for the neonatal complications, eight neonates were macrosomic or overweight, while 15 neonates required neonatal intensive care unit admission. Additionally, 13 patients had concurrent complications affecting both the mother and neonate. The glycated albumin level in patients with complications was 12.87%, which was significantly higher than that in patients without complications (glycated albumin, 11.67%) (P<0.001). The optimal cutoff value of glycated albumin for predicting maternal and neonatal complications was 12.45%. The sensitivity, specificity, and Youden index were 66.7 %, 86.7%, and 0.534, respectively.
Conclusion
The third trimester glycated albumin test in mothers with gestational diabetes provides limited predictive value for maternal and neonatal complications.

Background
Family caregivers should focus on maintaining independence when assisting older adults with mobility. This may, however, bring about a counterproductive effect, namely Informal Caregiver-induced Forced Immobility (ICFI). This study explored the perceptions and experiences of older adults and their informal caregivers regarding ICFI.
Methods
This qualitative study used a conventional content analysis approach and was conducted from January to September 2023 in Tabriz, Iran. Twenty older adults (aged 60 years and above) who had used a mobility aid, such as a cane or walker, and 14 informal caregivers were purposefully (purposive sampling) selected to participate in the study. Individual semi-structured interviews were conducted until data saturation was achieved. MAXQDA ver. 20.0 software (VERBI Software, Germany) was used to manage and analyze the data.
Results
Based on the participants’ perceptions, ICFI means that for an older adult, “social interaction/social participation is limited,” “performing activities of daily living is disallowed,” and “engaging in physical activities and exercising is prohibited.”
Conclusion
Our findings revealed the concept of ICFI from various perspectives in Iranian families with older adults, leading to a clearer understanding of this phenomenon. This aspect should be considered when developing intervention strategies for the care of older adults in home and residential care settings by, health practitioners, gerontologists, and policymakers. This research can serve as a foundation for future studies to develop pertinent indicators and tools for measuring ICFI in the hope of providing sufficient evidence to support interventions that aim to prevent or stop ICFI.

Background
The influx of immigrants into Korea has increased in recent years, affecting Korean society and the healthcare system. This study analyzed the frequency of anxiety and depression in immigrants, which negatively affects their quality of life.
Methods
We analyzed data from a 2020 survey on the Health Rights of Migrants and the Improvement of the Medical Security System. Bivariate analyses and a multiple logistic regression model were used to identify the risk factors associated with the presence of anxiety or depression among immigrants.
Results
We included 746 immigrants, 55.9% of whom were female. The overall rate of anxiety or depression was 31.77%, with 38.3% in females, which was significantly higher than the 26.62% in males. The frequency of anxiety and depression was also strongly associated with certain immigrant groups, including immigrants of African or Western Asian origin (over 64%); those with student visas (60.53%); those who self-reported poor health (52%), physical or mental disabilities (69.23%), or chronic diseases (58.43%); and those facing difficulties accessing medical services (59.47%).
Conclusion
This study showed the frequency of feelings of anxiety or depression and associated risk factors among immigrants. These findings may have implications for policymakers in reducing the likelihood of developing anxiety or depression in the future and improving the quality of life of immigrants in Korea.

Background
Although the association between smoking and health-related quality of life (HRQoL) has been established, the effects of tobacco products, including combustible cigarettes (CCs) and non-combustible nicotine or tobacco products (NNTPs), on HRQoL remain unclear. This study examined the association between tobacco use and HRQoL in Korean men.
Methods
Data from the Korea National Health and Nutrition Examination Survey conducted between 2013 and 2020 were analyzed. A total of 16,429 male participants aged ≥19 years completed the European Quality of Life-5 Dimensions (EQ-5D). Impaired HRQoL was defined as scoring in the lowest 20% of the EQ-5D index and having some or extreme problems in the following five domains of the EQ-5D: mobility, self-care, usual activities, pain/ discomfort, and anxiety/depression. Multiple logistic regression was conducted to evaluate the risk of impaired HRQoL in current tobacco users.
Results
Current tobacco users exhibited a significantly higher risk of impaired HRQoL compared with never users (odds ratio [OR], 1.42; 95% confidence interval [CI], 1.05–1.92). Compared to never users, current tobacco users reported more problems with mobility and pain/discomfort (all P<0.05). Moreover, compared with former tobacco users, current tobacco users had a higher risk of impaired HRQoL (OR, 1.60; 95% CI, 1.18–2.17). Compared to former tobacco users, current tobacco users reported more problems with mobility and pain/discomfort (all P<0.05).
Conclusion
Use of CCs and NNTPs is associated with impaired HRQoL in Korean men. Therefore, further interventions for lifestyle modification and smoking cessation treatments are required to reduce the risk of impaired HRQoL among current tobacco users.

Background
Whether land- or aquatic-based rehabilitation is more effective in improving knee osteoarthritis (OA) is still unclear. This study assessed the effectiveness of aquatic-based treatments in patients with knee OA.
Methods
The participants were divided into a land-based exercise group (G1, n=30) and a water-based exercise group (G2, n=30). The exercises were performed for 8 weeks. The primary endpoint was a response to physical therapy, defined as a 20% decrease in the summed score for the Western Ontario and McMaster Universities-Osteoarthritis Index (WOMAC) pain subscale from T1 (before the start of the rehabilitation program) to T2 (8 weeks later). The secondary endpoints included the Visual Analog Scale (VAS) for pain, WOMAC functional and stiffness subscales, Lequesne Index, and Medical Outcome Study Short Form (SF-12) for physical and mental health.
Results
A 20% decrease in the summed WOMAC pain subscale score was noted in 33% of patients in G1 (n=10) and 93% in G2 (n=28) (P<0.001). VAS scores at walking decreased by 14% in G1 vs. 37% in G2 (P<0.001), WOMAC stiffness subscale decreased by 18% in G1 vs. 53% in G2 (P<0.001), and the Lequesne index decreased by 10% in G1 vs. 33% in G2 (P<0.001). Quality of life improvement was greater in G2 than in G1; SF-12 (physical) increased by 2.3 in G1 vs. 5.4 in G2 (P=0.023), and SF-12 (mental) increased by 6.3 in G1 vs. 10.9 in G2 (P=0.022).
Conclusion
Both aquatic and land-based exercises improved pain intensity, functional impairment, degree of handicap, and quality of life impairment caused by OA. However, the improvement was more significant in the aquatic-based exercises group.

Citations

• Effects of Eight Weeks of Aquatic Therapy on Knee Proprioception and Gait Speed Among Female Older Adults with Knee Osteoarthritis: A Randomized Clinical Trial
  Zahra Bagherpoor Kalkhoran, Razieh Khanmohammadi
  Middle East Journal of Rehabilitation and Health Studies.2024;[Epub]     CrossRef

Background
The liver plays an important role in gonadal steroid hormone metabolism, which can affect reproductive health, including the menstrual cycle. However, evidence from large population-based studies is limited. Therefore, this study aimed to investigate the association between liver function markers and menstrual cycle irregularities in premenopausal Korean women using nationwide data.
Methods
This study analyzed Data from the Korea National Health and Nutrition Examination Survey 2010–2011. We investigated 3,045 premenopausal women aged 19–59 years. Liver function markers including serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase, and fatty liver index were analyzed. Multivariable logistic regression analysis was performed to investigate the association between liver function markers and menstrual cycle irregularity while adjusting for confounding factors. Values were presented as odds ratios (ORs) with 95% confidence intervals (CIs). Subgroup analysis was also performed.
Results
Baseline characteristic analysis showed that approximately 14.4% of the study population experienced menstrual cycle irregularity. The mean age was 34.5±0.7 years. The highest quartile of serum ALT and AST levels showed significantly higher ORs for menstrual cycle irregularity (adjusted OR, 1.83; 95% CI, 1.26–2.64 and adjusted OR, 1.67; 95% CI, 1.17–2.39, respectively). A similar result was observed in the subgroup analysis.
Conclusion
Liver function markers were positively associated with menstrual cycle irregularities. In clinical settings, women of reproductive age with relatively decreased liver function should be considered for regular followup of their reproductive health status.

Background
Insulin resistance contributes to the development of cardiovascular disease and type 2 diabetes mellitus. Smoking leads to an increase in triglyceride levels, which, in turn, increases insulin resistance. Although the number of e-cigarette users has increased in recent years, few studies have investigated the association between ecigarette use and insulin resistance. Therefore, this study aimed to determine the association between e-cigarette use and insulin resistance using the triglyceride-glucose (TyG) index in Korean adults.
Methods
This study included 4,404 healthy adults aged ≥20 years who participated in the Korea National Health and Nutrition Examination Survey between 2019 and 2020. Participants were categorized as never-smokers or ecigarette users, and the TyG index was categorized into low- and high-TyG index groups according to the median value (9.22). A logistic regression analysis was performed to determine the association between e-cigarette smoking and insulin resistance.
Results
E-cigarette users had a higher TyG index than never smokers (e-cigarette: mean=3.95; never: mean=9.18; P<0.001). The e-cigarette users had a higher risk of being in the high TyG index group than never-smokers (odds ratio [OR], 1.38; 95% confidence interval [CI], 1.03–1.84). In the subgroup analysis stratified by sex, age, and body mass index, a higher OR for a high TyG index was observed in men (OR, 1.46; 95% CI, 1.03–2.08) and individuals aged 60 years or older (OR, 3.74; 95% CI, 1.14–12.30).
Conclusion
Our findings suggest that e-cigarette use is significantly associated with insulin resistance.

Background
The Korean Journal of Family Medicine (KJFM), which is an official journal of the Korean Academy of Family Medicine, is an English-text medical journal published since 2009. Although nearly 15 years have passed since the journal was launched, to the best of our knowledge, no study has reviewed articles published in the KJFM. Accordingly, we analyzed articles published in the KJFM for the first time.
Methods
Articles published in the KJFM between January 2018 and November 2023 were categorized according to article type. Information about author affiliations, study subjects, research methods, and modes of data collection was then scrutinized. Moreover, we compared the frequencies of subjects, research methods and modes of data collection before, during, and after the coronavirus disease 2019 pandemic.
Results
Original article was the most common article type. Approximately 52% of the articles were published by authors affiliated with departments other than family medicine, and 40% were published by family medicine. Approximately 60% and 38% of the articles were published by Korean authors and authors of international affiliations, respectively. Throughout the pandemic periods, research subjects focusing on “diseases & symptoms” have diminished, while “principles of family medicine” have progressively increased. Additionally, the use of cross-sectional study methods has declined. In terms of data collection, the use of “big data,” “medical records,” and “questionnaires” has decreased, whereas the use of “study results” has increased.
Conclusion
KJFM is journal with wide and international participation covering various research subjects and study methods. We believe that our study provides valuable data for the future direction and development of the KJFM.

Background
No disease-specific, reliable, and valid self-assessment tools exist for athletes with mild coronavirus disease (COVID-19) to self-return to sports. This study aimed to develop a self-assessment screening method for athletes with mild COVID-19.
Methods
Item generation, item reduction, and pretesting were used to develop a questionnaire that served as a screening tool to detect severe post-COVID-19 complications. The questionnaire was validated by both internal and external reviewers, and the final version consisted of 11 items. Face validity was assessed through direct interviews with 11 athletes. Severe COVID-19 complications were identified for criterion validity and correlation analysis. A total score of 11 indicates that there is no risk of severe COVID-19 complications and gradual return to play is recommended; results <11 indicate a need for further evaluation by trained medical personnel. For reliability test, 50 respondents were chosen and asked to answer the questionnaires 7 days after their first responses.
Results
Physical Activity Readiness Questionnaires for post-COVID-19 athletes (PAR-COVID-Q) demonstrated excellent internal consistency (r=1, P<0.05) and test-retest reliability (r=1, P<0.05). A total of 118 athletes scored 11, had normal health screening, normal electrocardiogram and chest X-ray, and successfully returned to sports without any reported complications (r=1, P<0.05). Two athletes scored <11 and underwent further medical evaluation.
Conclusion
The PAR-COVID-Q is a valid and reliable self-assessment tool with a low burden for athletes to return to sports following mild COVID-19.

Background
Circadian misalignment is associated with metabolic syndrome. This study aimed to examine the association between circadian rhythm-disturbing factors and metabolic syndrome.
Methods
We used data from the 7th and 8th Korea National Health and Nutrition Examination Survey conducted between 2016 and 2020, which surveyed 16,253 individuals. Circadian rhythm-disturbing factors were defined as follows: sleep duration outside the reference group (6–8 hours), irregular breakfast, shift work, and physical inactivity. The adjusted odds ratio (aOR) for metabolic syndrome was calculated based on the number of circadian rhythm-disturbing factors present in adults over the age of 19 years.
Results
Among a total of 16,253 participants (mean age 48.2±15 years), metabolic syndrome was found in 5,237 participants (29.3 %). The participants were classified into three categories based on the number of circadian rhythm-disturbing factors as follows: 2,627 (15.6%) did not have any factors, 6,406 (38.13%) had one factor, and 7,220 (46.3%) had two or more factors. Participants with a single circadian rhythm-disturbing factor were 21% more likely to have metabolic syndrome (aOR, 1.21; 95% confidence interval [CI], 1.08–1.36), and participants with two or more factors were 27% more likely to have metabolic syndrome (aOR, 1.27; 95% CI, 1.12–1.43).
Conclusion
Circadian rhythm-disturbing factors were significantly associated with the prevalence of metabolic syndrome in Korean adults. This finding has potential clinical implications for maintaining circadian rhythms by avoiding certain factors to prevent metabolic syndrome. Further studies are required to confirm these findings.

Background
Female workers in Indonesia are vulnerable, because they must work to earn a living while still being responsible for domestic problems. This study analyzes the barriers to the use of modern contraceptives by female workers in Indonesia’s urban areas.
Methods
This cross-sectional survey looked at 21,696 female workers. We used modern contraceptive use as a dependent variable, and age, education, wealth, known modern contraceptives, number of live births, ideal number of children, and insurance ownership as independent variables. In the final test, we employed binary logistic regression.
Results
The results showed that women at all age categories were more likely than those aged 15–19 years not to use modern contraceptives, except those aged 35–39 years, who showed no difference. All other marital types were more likely to use modern contraceptives than married individuals. Rich female workers were 1.139 times more likely than poor workers not to use modern contraceptives (adjusted odds ratio [AOR], 1.139; 95% confidence interval [CI], 1.026–1.264). Female workers who did not know about modern contraceptives were 4.549 times more likely than those who did not to use modern contraceptives (AOR, 4.549; 95% CI, 1.037–19.953). Female workers with more than two children were 9.996 times more likely than those with two or fewer children not to use modern contraceptives (AOR, 9.996; 95% CI, 9.1890–10.875).
Conclusion
This study identified five factors associated with the non-use of modern contraceptives by female workers in Indonesia’s urban areas: young, unmarried, rich, did not know about modern contraceptives, and had more than two children.

Background
The relationship between weight change and quality of life remains controversial. This study aimed to investigate whether changes in body weight among participants in different baseline body mass index categories are associated with physical and mental health functioning.
Methods
We conducted an analysis involving 5,106 adults who participated in the Korean Genome and Epidemiology Study, a cohort comprising Korean adults aged 40 to 69 years. We categorized participants into three groups based on body weight change, and physical and mental health were assessed using the 12-Item Short-Form Health Survey in year 4. We employed logistic regression analysis to assess the association between body weight change and poor functioning at year 4. We also utilized a generalized estimating equation to determine the relationship between weight changes and mental component summary (MCS) scores over the study period for each weight group.
Results
Weight gain in both the normal weight (odds ratio [OR], 1.88; 95% confidence interval [CI], 1.13–3.11; P=0.01) and overweight groups (OR, 1.75; 95% CI, 1.05–2.91; P=0.03) was associated with poor MCS. Normal weight weight-losers were associated with a greater increase (2.69 points; 95% CI, 0.50–4.88) in MCS compared to weightmaintainers. Significant differences in mean MCS were observed for overweight weight-losers, obese weight-gainers, and underweight weight-gainers when compared to weight maintainers in each respective weight group.
Conclusion
Different patterns of relationships between weight change and mental health-related quality of life were observed. Hence, it is crucial to focus on the mental health of middle-aged and older adults when assessing body weight changes.

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.

Background
Malnutrition is common among children under 5 years of age in Indonesia, with the rates varying between urban and rural areas. The minimum acceptable diet (MAD) assesses nutrient quality and quantity. This study aimed to identify the potential variables for MAD in 6–23-month-old children in both urban and rural Indonesia.
Methods
We used the data from the 2017 Indonesia Demographic and Health Survey to conduct this nationally representative study. A total of 4,688 children aged 6–23 months were included in the study. MAD was classified using the 2017 World Health Organization global nutrition monitoring framework. The determinants of MAD were analyzed using multiple logistic regression.
Results
Overall, 45% of children aged 6–23 months received the required MAD, with 47.4% receiving the MAD in urban areas and 35.7% in rural areas. Children’s age, fathers’ age, parents’ education level, mothers’ employment, and wealth index were strongly linked to MAD in both rural and urban homes. The factor specifically related to MAD in urban areas was mother living with her husband. For rural households, mothers’ involvement in decisionmaking and a minimum of four antenatal care (ANC) visits significantly increased the likelihood of their children’s MAD status.
Conclusion
MAD status was determined by increased child age, higher parent education, younger father, working mother, and higher wealth index in children aged 6–23 months in both urban and rural settings. Mothers living with a spouse determined the MAD status only in urban areas. More frequent ANC visits and mother participation in household decisions were other factors related to MAD status in rural areas.

Background
Establishing cost-effective informal care services for lonely older adults living at home in developing countries can be an innovative approach for improving their well-being. This study investigated the effectiveness of an informal home care support intervention program (HoSIP) reducing the loneliness and improving quality of life of lonely community-dwelling older adults.
Methods
This quasi-experimental pre-post study employed a non-randomized control group design with a 12-week intervention period and three follow-up points at the end of the HoSIP. Questionnaires were used to measure feelings of loneliness (20-item UCLA Loneliness Scale), quality of life (Control, Autonomy, Self‐Realization and Pleasure Scale), general health (12-item General Health Questionnaire), social network (six-item Lubben Social Network Scale), social support (12-item Multidimensional Scale of Perceived Social Support), and self-care ability (17-item Self-care Ability Scale for the Elderly). Repeated-measures analysis of variance was used to gauge the effect of the intervention program over time and in comparison to the control group. Data analyses were performed using the IBM SPSS Statistics software (IBM Corp., USA).
Results
We found a significant relationship between the outcome variables, including feelings of loneliness (P<0.001) and quality of life (P<0.001), at different stages of measurement. Despite the positive feasibility results, the implementation of the HoSIP faced challenges due to a lack of facilities (e.g., place restriction for holding educational classes, educational facilities like computers, video projector, and whiteboard at daycare center) and the absence of supporting organizations.
Conclusion
Utilizing the existing capabilities of older adults to provide online and face-to-face care services can be a cost-effective way to improve their quality of life and reduce loneliness. The process of facilitating such informal care services for lonely older adults should be managed by either governmental or non-governmental organizations to reduce the rate of social isolation among this vulnerable population.