National Trends in Physical Activity Among Adults in South Korea Before and During the COVID-19 Pandemic, 2009-2021

Impact of the COVID-19 pandemic on the incidence of cardiometabolic risk factors among workers: results from the Japan Epidemiology Collaboration on Occupational Health study

BACKGROUND

The COVID-19 pandemic and associated restrictions on human activities have greatly changed lifestyles, which might have deteriorated the cardiometabolic profile.

OBJECTIVE

This study aimed to examine the effect of the COVID-19 pandemic on the incidence of cardiometabolic risk factors among Japanese workers in fiscal years (FY) 2020 and 2021 compared with the prepandemic period.

METHOD

This study comprised an average of 71 025 employees in Japan who underwent annual health check-ups for at least two successive years from 2015 to 2021. Annual incidence rates from 2016 to 2021 were assessed for obesity, diabetes, hypertension, dyslipidaemia and metabolic syndrome (MetS). The observed incidence rates in 2020 and 2021 were compared with the predicted incidence based on prepandemic trends (2016 to 2019).

RESULTS

Relative to the prepandemic, the incidence of all the outcomes, except for dyslipidaemia, significantly increased in 2020. Between FY 2016 and 2019, the adjusted mean incidence of obesity, diabetes, hypertension, dyslipidaemia and MetS was 5.0%, 1.4%, 5.3%, 17.4% and 7.6%, respectively. In FY 2020, the adjusted incidence (95% CI) of these outcomes increased to 6.02 (5.80 to 6.24), 1.84 (1.73 to 1.96), 6.62 (6.40 to 6.83), 19.31 (18.83 to 19.78) and 8.51 (8.23 to 8.78), which were higher than the predicted incidence of 5.24 (4.99 to 5.49), 1.54 (1.41 to 1.67), 6.02 (5.76 to 6.27), 18.58 (18.00 to 19.16) and 8.05 (7.71 to 8.38) for 2020, respectively. The incidence returned to the prepandemic levels in FY 2021.

CONCLUSION

Results showed a worsening of the cardiometabolic profile during the initial year of the pandemic, which was reverted in the second year to the levels before the pandemic.

Long-term trends and patterns in ultra-processed food consumption among Korean adults from 1998 to 2022

Ultra-processed foods are linked to adverse health outcomes, making it crucial to monitor consumption trends. Despite rising consumption due to Westernized diets in Asia, long-term studies targeting Asian adults are lacking. Thus, we analyzed ultra-processed food consumption trends among Korean adults from 1998 to 2022. Additionally, we compared intakes before and during the pandemic to evaluate the potential impact of the COVID-19 pandemic. Furthermore, we compared the nutrient profiles of ultra-processed and non-ultra-processed food group intakes. This study used data from the Korea National Health and Nutrition Examination Survey (KNHANES) from 1998 to 2022, classifying food into four NOVA groups. Dietary intake was assessed In 2020-2022, ultra-processed foods had a higher proportion using a single 24-hour recall for 96,447 individuals aged 20 years or older. Sampling weights were applied to adjust for the complex survey design and non-responses. We calculated the weighted means and confidence intervals for the proportion of energy intake by NOVA food groups and various nutrient profiles. The proportion of energy intake from ultra-processed foods among Korean adults steadily increased from 17.41% in 1998-2005 to 26.71% in 2016-2019 (mean difference: 9.30% [95% CI, 8.62-9.98%]), but declined for the first time during the pandemic, falling to 25.33% (mean difference: -1.39% [95% CI, -2.18% to -0.59%]). In 2020-2022, ultra-processed foods had a higher proportion of calories from carbohydrates (62.12% vs. 58.81%) and fats (28.22% vs. 22.31%) but a lower proportion from protein (10.32% vs. 17.26%) compared to non-ultra-processed foods. From 1998 to 2022, the fat content of both ultra-processed and non-ultra-processed foods significantly increased, rising from 26.24 to 28.15% for ultra-processed foods (mean difference: 1.91% [95% CI, 1.33-2.49%]) and from 16.81 to 22.26% for non-ultra-processed foods (mean difference: 5.45% [95% CI, 4.99-5.91%]). This study examined 25-year trends in ultra-processed food consumption among South Koreans, showing a consistent increase in energy intake from ultra-processed foods until the COVID-19 pandemic, during which it declined for the first time. However, this decline may be temporary, underscoring the need for sustained efforts to reduce ultra-processed food consumption.

Association between behavioral and sociodemographic factors and high subjective health among adolescents: a nationwide representative study in South Korea

The need to understand subjective health has increased during the COVID-19 pandemic, given its substantial impact on lifestyle habits and perceptions. Thus, this study aimed to investigate the trends and association of subjective health with demographic and behavioral factors, primarily focusing on the change when the COVID-19 pandemic emerged. This study used data from the Korea Youth Risk Behavior Web-based Survey, comprising 1,190,468 adolescents aged 12-18 years (female, 48.49%). We investigated the trends and association of subjective health with demographic and behavioral factors from 2006 to 2023. A weighted linear regression and joinpoint regression were conducted to evaluate the trend in adolescent subjective health, while logistic regression was used to assess associated factors. A stratification analysis was performed for subgroups to determine variations across different demographic and behavioral groups. The prevalence of reporting high subjective health increased throughout the years before the COVID-19 pandemic; however, subjective health exhibited a decreasing trend during the pandemic. Regarding demographic factors, female sex (ratio of odds ratio [ROR], 0.85 [95% CI, 0.83-0.87]), low-income households (ROR, 0.67 [95% CI, 0.64-0.69]), and low academic achievement (ROR, 0.83 [95% CI, 0.81-0.85]) were associated with less likelihood of reporting high subjective health. Healthier behavioral factors (ROR, breakfast consumption, 1.13 [95% CI, 1.10-1.16]; sufficient fruit intake, 1.12 [95% CI, 1.09-1.15]; sufficient physical activity, 2.02 [95% CI, 1.95-2.09]) were associated with higher subjective health, and the disparities increased during the COVID-19 pandemic. To address the observed decline in subjective health among adolescents during the COVID-19 pandemic, targeted interventions aimed at promoting healthy behaviors among particularly vulnerable demographics are crucial.

Associations between weight-control methods and depression among Korean adolescents: a study based on a national dataset

BACKGROUND/OBJECTIVES

The increasing prevalence of overweight and obesity has become a significant global burden, with more than 40% of the global adult population attempting to lose weight. Previous studies on the impact of weight-control methods on mental health, especially among adolescents, are limited. Thus, this study aimed to investigate the association between various weight-control methods and depression among adolescents, with the goal of informing healthier weight management decisions and promoting effective methods.

SUBJECTS/METHODS

This nationwide study utilized data from the Korea Youth Risk Behavior Web-based Survey, including a sample of 418,254 adolescents collected over 12 yrs (2007-2019). We conducted a weighted complex sample analysis to compare depression rates associated with specific weight-control methods, including exercise, fasting (≥ 24 h), eating less, taking prescription/non-prescription weight-loss medication, taking laxatives or diuretics, vomiting, one-food diet, taking oriental medicine, and diet foods.

RESULTS

Of the 418,254 participants, 45.96% (192,246) were male. Among male participants, fasting (≥ 24 h; weighted odds ratio [wOR], 1.43; 95% confidence interval [CI], 1.36-1.51) and vomiting (wOR, 1.49; 95% CI, 1.35-1.66) were associated with an increased risk of depression. Among female participants, prescribed (wOR, 0.82; 95% CI, 0.74-0.90) and non-prescribed (wOR, 0.89; 95% CI, 0.82-0.97) weight-loss medication reduced the risk of depression. However, fasting (≥ 24 h; wOR, 1.47; 95% CI, 1.41-1.52) and vomiting (wOR, 1.45; 95% CI, 1.36-1.55) significantly increased the risk of depression.

CONCLUSION

The risk of depression varies depending on the weight-control method, with a consistent trend observed across both sexes. Methods such as vomiting, fasting, taking oriental medicine for weight loss, and consuming diet foods increased the risk of depression, while weight-loss medications were associated with reduced depression symptoms in females. These findings highlight the need for further research on weight-control medications and policies that support effective weight management while reducing depressive effects.

Comparison of national trends in physical activity among adolescents before and during the COVID-19 pandemic: A nationally representative serial study in South Korea

Background

The COVID-19 pandemic has dramatically altered daily routines and lifestyle behaviors worldwide, potentially significantly impacting physical activity levels, especially among adolescents. Understanding these changes is crucial for developing targeted interventions to promote health and well-being in this vulnerable population. This paper will explore longitudinal trends of physical activities (PA) in Korean adolescents, focusing on changes between the pre and late-COVID-19 pandemic periods.

Methods

The data used were from the Korea Youth Risk Behavior Web-Based Survey for consecutive years from 2009 to 2022. In this study, we have separated data into the pre-COVID-19 pandemic (2009-2019) and the pandemic. Following the World Health Organization (WHO)'s guideline, we analyzed adolescent self-reported moderate-to-vigorous physical activity (MVPA).

Results

A total of 890,941 adolescents, people aged between 12 and 18 years old. The 14-year trends in MVPA showed an upward trend both before the pandemic (β, 0.005; 95 % confidence interval [CI], 0.004-0.005) and during the pandemic (β, 0.004; 0.002-0.006). Furthermore, the prevalence of MVPA recovered/increased in 2022 (5.61 % in 2020, 5.22 % in 2021, and 6.34 % in 2022). Similar to the MVPA patterns, the mean metabolic equivalent task (MET) score increased during before the pandemic (β, 15.392; 12.523-18.261) and during the pandemic (β, 49.518; 41.948-57.088). However, unlike MVPA patterns, the MET slope changed positively (βdiff, 34.126; 26.031-42.221).

Conclusion

Present findings suggest that Korean adolescents achieving the recommended PA levels by the WHO remained steady despite the pandemic. This stability in PA levels during a significant disruption (i.e. the COVID-19 pandemic) is noteworthy and warrants further investigation into the factors that may have contributed to this resilience, including potential influences from various societal and environmental elements.

Active sport participation and walking before and during COVID-19 pandemic in a large cohort of Polish adults: results of the National Test for Poles' Health

OBJECTIVES

The COVID-19 pandemic has led to significant changes in daily life, including changes in physical activity levels. This study aims to examine the impact of the pandemic on sport participation and walking among Polish adults.

MATERIAL AND METHODS

The data was collected using the National Test for Poles' Health, a large-scale online survey. The survey was conducted before and 1 year after the pandemic onset in Poland (March 2020 and March 2021), with >300 000 participants in each year.

RESULTS

The results revealed that the percentage of respondents engaging in at least 2 h/week of sport increased by 2.3% (from 24.6% to 26.9%) (p < 0.0001) and percentage of respondents not engaging in any sport decreased by 2.5% (from 48.0% to 45.5%) (p < 0.0001). These trends were observed across different age, sex, dwelling-place, education level, and employment groups. Percentage of respondents declaring they spend >2 h/day on walking also increased, from 5.6% to 6.6% (p < 0.0001). Furthermore, a positive association was found between sport participation and walking time (p < 0.0001).

CONCLUSIONS

The findings suggest a slight improvement in physical activity levels among Polish adults during the pandemic, which may be attributed to factors such as increased time available due to remote work and the prioritization of health during the crisis. Further research is needed to explore the long-term consequences of the pandemic on physical activity and public health. Int J Occup Med Environ Health. 2024;37(4):468-81.

Association Between Sociodemographic Factors and Vaccine Acceptance for Influenza and SARS-CoV-2 in South Korea: Nationwide Cross-Sectional Study

Background

The imperative arises to study the impact of socioeconomic factors on the acceptance of SARS-CoV-2 and influenza vaccines amid changes in immunization policies during the COVID-19 pandemic.

Objective

To enhance targeted public health strategies and improve age-specific policies based on identified risk factors, this study investigated the associations between sociodemographic factors and vaccination behaviors during the COVID-19 pandemic, with emphasis on age-specific vaccine cost policies.

Methods

This study analyzed data from the Korean Community Health Survey 2019-2022 with 507,964 participants to investigate the impact of age-specific policies on vaccination behaviors during the pandemic period. Cohorts aged 19-64 years and 65 years or older were stratified based on age (years), sociodemographic factors, and health indicators. The cohorts were investigated to assess the influence of relevant risk factors on vaccine acceptance under the pandemic by using weighted odds ratio and ratio of odds ratio (ROR).

Results

Among 507,964 participants, the acceptance of the SARS-CoV-2 vaccine (COVID-19 vaccine) was higher among individuals with factors possibly indicating higher socioeconomic status, such as higher education level (age 19-64 years: ROR 1.34; 95% CI 1.27-1.40 and age ≥65 years: ROR 1.19; 95% CI 1.01-1.41) and higher income (age 19-64 years: ROR 1.67; 95% CI 1.58-1.76 and age ≥65 years: ROR 1.21; 95% CI 1.06-1.38) for both age cohorts compared to influenza vaccine acceptance before the pandemic. In the context of influenza vaccination during the pandemic, the older cohort exhibited vaccine hesitancy associated with health care mobility factors such as lower general health status (ROR 0.89; 95% CI 0.81-0.97).

Conclusions

SARS-CoV-2 vaccination strategies should focus on reducing hesitancy among individuals with lower social participation. To improve influenza vaccine acceptance during the pandemic, strategies for the younger cohort should focus on individuals with lower social participation, while efforts for the older cohort should prioritize individuals with limited access to health care services.

Sex-Specific Trends in the Prevalence of Osteoarthritis and Rheumatoid Arthritis From 2005 to 2021 in South Korea: Nationwide Cross-Sectional Study

BACKGROUND

Osteoarthritis and rheumatoid arthritis (RA) are prevalent chronic joint disorders, with prevalence rates varying by sex. However, few studies have comprehensively documented the factors contributing to the sex-specific prevalence of osteoarthritis and RA, including sociological factors and the impact of the COVID-19 pandemic.

OBJECTIVE

This study aims to identify long-term trends in the sex-specific prevalence of osteoarthritis and RA from 2005 to 2021 while examining the factors that serve as vulnerabilities specific to each sex within the context of the COVID-19 pandemic.

METHODS

Data were collected from a nationally representative sample of 110,225 individuals through the Korea National Health and Nutrition Examination Survey from 2005 to 2021. The study included patients aged 19 years and older diagnosed with osteoarthritis or RA in South Korea. Data were analyzed using weighted trends to accurately represent the sample population, with a 95% CI. Weighted logistic and regression models were used to identify vulnerable groups at risk of osteoarthritis or RA during the pandemic to assess sex-specific trends.

RESULTS

In total, 110,225 individuals (n=48,410, 43.92% male participants) were analyzed from 2005 to 2021, with prevalence rates remaining stable over time and higher in female than in male participants. Notably, during the pandemic, female participants aged 60 years and older exhibited a prevalence of osteoarthritis that was 4.92 times greater than male participants and a prevalence of RA that was 6.44 times greater (osteoarthritis: prevalence ratio [PR] 69.78, 95% CI 41.66-116.88; RA: PR 17.27, 95% CI 8.75-34.07). In terms of osteoarthritis, male participants did not show a significant association with BMI (PR 1.40, 95% CI 1.21-1.61; P=.47), whereas female participants exhibited a significantly higher vulnerability within the obese group (PR 1.68, 95% CI 1.55-1.83; P<.001). Regarding RA, lower education levels were associated with increased vulnerability, with male participants showing a greater risk than female participants (male participants: PR 2.29, 95% CI 1.61-3.27 and female participants: PR 1.50, 95% CI 1.23-1.84).

CONCLUSIONS

This study reveals that women in South Korea have a higher prevalence of osteoarthritis and RA than men. Understanding these sex-specific trends and identifying vulnerability factors can enhance preventive efforts and patient care.

National trends in type 2 diabetes mellitus stratified by central adiposity using waist-to-height ratio in South Korea, 2005-2022

Studies investigating the association between type 2 diabetes mellitus and central adiposity are lacking. Therefore, this study aimed to investigate trends in type 2 diabetes mellitus stratified by central adiposity using waist-to-height ratio (WHtR). Trends in type 2 diabetes mellitus were examined by central adiposity, using WHtR, with data from the Korea National Health and Nutrition Examination Survey (2005-2022). Individuals aged 30 years and over who participated in the survey were selected. Type 2 diabetes mellitus was identified based on serum glucose or HbA1c levels, the use of diabetes medications, or a prior diagnosis by a physician. Weighted β-coefficients or odd ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess changes in disease prevalence. A total of 79,368 participants were included in the database (female: 45,163 [56.9%]). from 2005 to 2022, the prevalence of type 2 diabetes mellitus increased from 3.3 to 5.8% in the healthy central adiposity group, from 11.2 to 17.1% in the increased central adiposity group, and from 18.0 to 26.7% in the high central adiposity group. Males, older population, lower education level, lower household income, and smoking are associated with a higher risk of type 2 diabetes. In the high central adiposity group, overweight and obese individuals had higher susceptibility than underweight or normal-weight individuals, with ORs of 5.85 (95% CI, 2.54-13.47) and 8.24 (3.79-17.94), respectively. The prevalence of type 2 diabetes mellitus has increased in all central adiposity groups in the past decade. This underscores the need for tailored interventions to address disparities and improve diabetes management in at-risk populations.

Psychosocial alterations during the COVID-19 pandemic and the global burden of anxiety and major depressive disorders in adolescents, 1990-2021: challenges in mental health amid socioeconomic disparities

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic, a global health crisis, profoundly impacted all aspects of daily life. Adolescence, a pivotal stage of psychological and social development, is heavily influenced by the psychosocial and socio-cultural context. Hence, it is imperative to thoroughly understand the psychosocial changes adolescents experienced during the pandemic and implement effective management initiatives.

DATA SOURCES

We examined the incidence rates of depressive and anxiety disorders among adolescents aged 10-19 years globally and regionally. We utilized data from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 to compare pre-pandemic (2018-2019) and pandemic (2020-2021) periods. Our investigation covered 204 countries and territories across the six World Health Organization regions. We conducted a comprehensive literature search using databases including PubMed/MEDLINE, Scopus, and Google Scholar, employing search terms such as "psychosocial", "adolescent", "youth", "risk factors", "COVID-19 pandemic", "prevention", and "intervention".

RESULTS

During the pandemic, the mental health outcomes of adolescents deteriorated, particularly in terms of depressive and anxiety disorders. According to GBD 2021, the incidence rate of anxiety disorders increased from 720.26 [95% uncertainty intervals (UI) = 548.90-929.19] before the COVID-19 pandemic (2018-2019) to 880.87 per 100,000 people (95% UI = 670.43-1132.58) during the COVID-19 pandemic (2020-2021). Similarly, the incidence rate of major depressive disorder increased from 2333.91 (95% UI = 1626.92-3138.55) before the COVID-19 pandemic to 3030.49 per 100,000 people (95% UI = 2096.73-4077.73) during the COVID-19 pandemic. This worsening was notably pronounced in high-income countries (HICs). Rapid environmental changes, including heightened social anxiety, school closures, economic crises, and exacerbated racism, have been shown to adversely affect the mental well-being of adolescents.

CONCLUSIONS

The abrupt shift to remote learning and the absence of in-person social interactions heightened feelings of loneliness, anxiety, sadness, and stress among adolescents. This change magnified existing socioeconomic disparities, posing additional challenges. These complexities profoundly impact adolescents' well-being, especially vulnerable groups like those from HICs, females, and minorities. Acknowledging the underreporting bias in low- to middle-income countries highlights the importance of addressing these mental health alterations in assessments and interventions within these regions as well. Urgent interventions are crucial as the pandemic-induced mental stress may have lasting effects on adolescents' mental health.

National Trends in the Prevalence of Unmet Health Care and Dental Care Needs During the COVID-19 Pandemic: Longitudinal Study in South Korea, 2009-2022

BACKGROUND

Although previous studies have investigated trends in unmet health care and dental care needs, most have focused on specific groups, such as patients with chronic conditions and older adults, and have been limited by smaller data sets.

OBJECTIVE

This study aims to investigate the trends and relative risk factors for unmet health care and dental care needs, as well as the impact of the COVID-19 pandemic on these needs.

METHODS

We assessed unmet health care and dental care needs from 2009 to 2022 using data from the Korea Community Health Survey (KCHS). Our analysis included responses from 2,750,212 individuals. Unmet health care or dental care needs were defined as instances of not receiving medical or dental services deemed necessary by experts or desired by patients.

RESULTS

From 2009 to 2022, the study included 2,700,705 individuals (1,229,671 men, 45.53%; 673,780, 24.95%, aged 19-39 years). Unmet health care needs decreased before the COVID-19 pandemic; however, during the pandemic, there was a noticeable increase (βdiff 0.10, 95% CI 0.09-0.11). Unmet dental care needs declined before the pandemic and continued to decrease during the pandemic (βdiff 0.23, 95% CI 0.22-0.24). Overall, the prevalence of unmet dental care needs was significantly higher than that for unmet health care needs. While the prevalence of unmet health care needs generally decreased over time, the β difference during the pandemic increased compared with prepandemic values.

CONCLUSIONS

Our study is the first to analyze national unmet health care and dental care needs in South Korea using nationally representative, long-term, and large-scale data from the KCHS. We found that while unmet health care needs decreased during COVID-19, the decline was slower compared with previous periods. This suggests a need for more targeted interventions to prevent unmet health care and dental care needs.

Sex-Specific and Long-Term Trends of Asthma, Allergic Rhinitis, and Atopic Dermatitis in South Korea, 2007-2022: A Nationwide Representative Study

INTRODUCTION

Although sex differences in allergic diseases such as atopic dermatitis (AD), allergic rhinitis (AR), and asthma are considered important, a limited number of studies during the COVID-19 pandemic investigated this aspect. Therefore, this study aimed to analyze sex-specific and long-term trends and risk factors for allergic diseases before and during the pandemic.

METHODS

This study utilized data from the Korea National Health and Nutrition Examination Survey, 2007-2022, including 92,135 participants aged 19 years and older. This study used weighted multivariate regression analysis to examine the estimates of related factors and assessed weighted odds ratios or β-coefficients for these factors across multiple categories.

RESULTS

During the study period (2007-2022), the prevalence of AR was more common in females than in males. Particularly in 2022, the prevalence among females was 19.3% (95% confidence interval, 17.3-21.3), while among males, it was 15.6% (13.8-17.4). The prevalence of AD and asthma showed a slight disparity between males and females. Before and during the pandemic, the prevalence of AD and AR showed a continuous increase (AD: from 2.8% [2.5-3.2] in 2007-2009 to 4.7% [3.9-5.4] in 2022; AR: from 11.7% [11.1-12.4] in 2007-2009 to 17.4% [16.0-18.9] in 2022), while asthma maintained a relatively stable trend. Moreover, this study identified several sex-specific factors that seem to be associated with a higher prevalence of allergic diseases in females, such as high household income, smoking, and being overweight or obese.

CONCLUSIONS

Throughout all the periods examined, females consistently exhibited a higher prevalence of AR compared to males. Moreover, the risk factors for males and females varied depending on the disease, with females generally facing a greater number of risk factors. Consequently, this study highlights the necessity for sex-specific health interventions and further research to comprehend the complex influence of socioeconomic factors and lifestyle choices on the prevalence and risk of AD, AR, and asthma.

INTRODUCTION

Although sex differences in allergic diseases such as atopic dermatitis (AD), allergic rhinitis (AR), and asthma are considered important, a limited number of studies during the COVID-19 pandemic investigated this aspect. Therefore, this study aimed to analyze sex-specific and long-term trends and risk factors for allergic diseases before and during the pandemic.

METHODS

This study utilized data from the Korea National Health and Nutrition Examination Survey, 2007-2022, including 92,135 participants aged 19 years and older. This study used weighted multivariate regression analysis to examine the estimates of related factors and assessed weighted odds ratios or β-coefficients for these factors across multiple categories.

RESULTS

During the study period (2007-2022), the prevalence of AR was more common in females than in males. Particularly in 2022, the prevalence among females was 19.3% (95% confidence interval, 17.3-21.3), while among males, it was 15.6% (13.8-17.4). The prevalence of AD and asthma showed a slight disparity between males and females. Before and during the pandemic, the prevalence of AD and AR showed a continuous increase (AD: from 2.8% [2.5-3.2] in 2007-2009 to 4.7% [3.9-5.4] in 2022; AR: from 11.7% [11.1-12.4] in 2007-2009 to 17.4% [16.0-18.9] in 2022), while asthma maintained a relatively stable trend. Moreover, this study identified several sex-specific factors that seem to be associated with a higher prevalence of allergic diseases in females, such as high household income, smoking, and being overweight or obese.

CONCLUSIONS

Throughout all the periods examined, females consistently exhibited a higher prevalence of AR compared to males. Moreover, the risk factors for males and females varied depending on the disease, with females generally facing a greater number of risk factors. Consequently, this study highlights the necessity for sex-specific health interventions and further research to comprehend the complex influence of socioeconomic factors and lifestyle choices on the prevalence and risk of AD, AR, and asthma.

Prevalence, Awareness, Treatment, and Control of Type 2 Diabetes in South Korea (1998 to 2022): Nationwide Cross-Sectional Study

BACKGROUND

Type 2 diabetes poses an increasing disease burden in South Korea. The development and management of type 2 diabetes are closely related to lifestyle and socioeconomic factors, which have undergone substantial changes over the past few decades, including during the COVID-19 pandemic.

OBJECTIVE

This study aimed to investigate long-term trends in type 2 diabetes prevalence, awareness, treatment, and control. It also aimed to determine whether there were substantial alterations in the trends during the pandemic and whether these changes were more pronounced within specific demographic groups.

METHODS

This study examined the prevalence, awareness, treatment, and control of type 2 diabetes in a representative sample of 139,786 South Koreans aged >30 years, using data from the National Health and Nutrition Examination Survey and covering the period from 1998 to 2022. Weighted linear regression and binary logistic regression were performed to calculate weighted β coefficients or odds ratios. Stratified analyses were performed based on sex, age, region of residence, obesity status, educational background, household income, and smoking status. β (difference) was calculated to analyze the trend difference between the prepandemic period and the COVID-19 pandemic. To identify groups more susceptible to type 2 diabetes, we estimated interaction terms for each factor and calculated weighted odds ratios.

RESULTS

From 1998 to 2022, a consistent increase in the prevalence of type 2 diabetes was observed among South Koreans, with a notable rise to 15.61% (95% CI 14.83-16.38) during the pandemic. Awareness followed a U-shaped curve, bottoming out at 64.37% (95% CI 61.79-66.96) from 2013 to 2015 before increasing to 72.56% (95% CI 70.39-74.72) during the pandemic. Treatment also increased over time, peaking at 68.33% (95% CI 65.95-70.71) during the pandemic. Control among participants with diabetes showed no substantial change, maintaining a rate of 29.14% (95% CI 26.82-31.47) from 2020 to 2022, while control among treated participants improved to 30.68% (95% CI 27.88-33.48). During the pandemic, there was a steepening of the curves for awareness and treatment. However, while the slope of control among participants being treated increased, the slope of control among participants with diabetes showed no substantial change during the pandemic. Older populations and individuals with lower educational level exhibited less improvement in awareness and control trends than younger populations and more educated individuals. People with lower income experienced a deceleration in prevalence during the pandemic.

CONCLUSIONS

Over the recent decade, there has been an increase in type 2 diabetes prevalence, awareness, treatment, and control. During the pandemic, a steeper increase in awareness, treatment, and control among participants being treated was observed. However, there were heterogeneous changes across different population groups, underscoring the need for targeted interventions to address disparities and improve diabetes management for susceptible populations.

National and Regional Trends in the Prevalence of Hypertension in South Korea Amid the Pandemic, 2009-2022: Nationwide Study of Over 3 Million Individuals

BACKGROUND

Understanding the association between hypertension prevalence and socioeconomic and behavioral variables during a pandemic is essential, and this analysis should extend beyond short-term trends.

OBJECTIVE

This study aims to examine long-term trends in the prevalence of participants diagnosed with and receiving treatment for hypertension, using data collected by a nationally representative survey from 2009 to 2022, which includes the COVID-19 pandemic era.

METHODS

A nationwide, population-based, cross-sectional study used data collected from the South Korea Community Health Survey between 2009 and 2022. The study sample comprised 3,208,710 Korean adults over a period of 14 years. We aimed to assess trends in the prevalence of participants diagnosed with and receiving treatment for hypertension in the national population from 2009 to 2022, with a specific focus on the COVID-19 pandemic, using weighted linear regression models.

RESULTS

Among the included 3,072,546 Korean adults, 794,239 (25.85%) were aged 19-39 years, 1,179,388 (38.38%) were aged 40-59 years; 948,097 (30.86%) were aged 60-79 years, and 150,822 (4.91%) were aged 80 years or older. A total of 1,426,379 (46.42%) were men; 761,896 (24.80%) and 712,264 (23.18%) were diagnosed with and received treatment for hypertension, respectively. Although the overall prevalence over the 14-year period increased, the upward trends of patients diagnosed with and receiving treatment for hypertension decreased during the COVID-19 pandemic era compared with the prepandemic era (β difference for trend during vs before the pandemic -.101, 95% CI -0.107 to -0.094 vs -.133, 95% CI -0.140 to -0.127). Notably, the trends in prevalence during the pandemic were less pronounced in subgroups of older adults (≥60 years old) and individuals with higher alcohol consumption (≥5 days/month).

CONCLUSIONS

This nationwide representative study found that the national prevalence of participants diagnosed with and receiving treatment for hypertension increased during the prepandemic era. However, there was a marked decrease in these trends during the prepandemic era, compared with the pandemic era, particularly among specific subgroups at increased risk of negative outcomes. Future studies are needed to evaluate the factors associated with changes in the prevalence of hypertension during the COVID-19 pandemic.

Association of Soda Drinks and Fast Food with Allergic Diseases in Korean Adolescents: A Nationwide Representative Study

INTRODUCTION

A high consumption of carbonated soft drinks (i.e., soda drinks) and fast food is potentially associated with the observed global rise in adolescent allergic diseases. Thus, our study aimed to examine the potential associations between the consumption of soda drinks and fast food and allergic conditions, identifying specific relationships across subgroups and each allergic condition (asthma, allergic rhinitis, and atopic dermatitis).

METHODS

This study uses large-scale data from the Korea Youth Risk Behavior Web-Based Survey (total n = 865,614). Soda drinks and fast food were defined by a self-reported questionnaire and allergic conditions by physician-diagnosed within 1 year. Multivariable logistic regression was used to analyze the weighted odds ratios (ORs), along with 95% confidence intervals (CIs), for allergic diseases associated with the intake of soda drinks and fast food.

RESULTS

Among 865,614 adolescents in grades 7-12 (male, 51.40%), patients with asthma, allergic rhinitis, and atopic dermatitis were 18,568 (2.15%), 153,536 (17.74%), and 59,014 (6.82%), respectively. Current asthma was associated with soda drinks (OR, 1.07; 95% CI, 1.03-1.12) and fast food consumption (1.25; 1.17-1.33). Interestingly, stronger associations were observed for female high schoolers, compared to male high schoolers and middle schoolers, in relation to the consumption of soda drinks (1.31; 1.19-1.44) and fast food (1.46; 1.26-1.69) with asthma. Current allergic rhinitis and atopic dermatitis had no significant association with fast food consumption and soda drinks.

CONCLUSION

This first large-scale study suggests that fast food and soda drinks consumption are potentially associated with current asthma, with stronger associations observed in females than males, underscoring the need for sex-specific allergy prevention programs.

National prevalence of atopic dermatitis in Korean adolescents from 2009 to 2022

Previous studies have examined the prevalence of allergic diseases in adolescents 1-2 years after the emergence of the COVID-19 pandemic. However, more data is needed to understand the long-term impact of COVID-19 on allergic diseases. Thus, we aimed to examine the trend of the atopic dermatitis prevalence in Korean adolescents before and during the COVID-19 pandemic across 14 years. Additionally, we analyze the risk factors of atopic dermatitis (AD) based on the results. The Korean Disease Control and Prevention Agency conducted the Korea Youth Risk Behavior Web-based Survey from 2009 to 2022, from which the data for this study were obtained. Prevalence trends were compared across subgroups, and the β difference (βdiff) was calculated. We computed odds ratios to examine changes in the disease prevalence before and during the pandemic. This study included a total of 917,461 participants from 2009 to 2022. The prevalence of atopic dermatitis increased from 6.79% (95% CI 6.66-6.91) in 2009-2011 to 6.89% (95% CI 6.72-7.05) in 2018-2019, then decreased slightly to 5.82% (95% CI 5.60-6.04) in 2022. Across the 14 years, middle school student status, low parent's highest education level, low household income, non-alcohol consumption, non-smoker smoking status, no suicidal thoughts, and no suicide attempts were associated with increased risk of atopic dermatitis, while female sex, rural residence, high BMI, low school performance, low household income, and no feelings of sadness and despair was associated with a small increase. This study examined the prevalence of atopic dermatitis across an 18-year, and found that the prevalence increased in the pre-pandemic then decreased during the start of the pandemic and remained constant throughout the pandemic. This trend could be explained mainly by the large scale social and political changes that occurred during the COVID-19 pandemic.

National trends in counseling for stress and depression and COVID-19 pandemic-related factors among adults, 2009-2022: A nationwide study in South Korea: Stress, depression, and pandemic

To investigate the long-term trends in counseling for stress and depression using data from a nationwide survey in South Korea. We conducted a nationwide serial, large-scale, cross-sectional, survey-based study using data from 2,903,887 Korean adults from the Korea Community Health Survey, 2009-2022. Our study investigated the trends and risk factors for counseling for stress and depression during the pre-pandemic (2009-2019) and pandemic era (2020-2022). The prevalence of counseling for stress and depression increased across pre-pandemic (counseling for stress: β, 0.217 [95 % CI, 0.194 to 0.241]; counseling for depression: β, 0.136 [0.118 to 0.154]) and pandemic periods (β, 0.324 [0.287 to 0.360]; β, 0.210 [0.182 to 0.239], respectively). The prevalence of counseling for stress and depression showed steeper slopes for increasing trends after the outbreak. In addition, subgroups with female sex, urban residence, lower household income, lower self-rated health, shorter sleep time, and higher worries about contracting COVID-19 were the risk factors associated with the increased prevalence of counseling for stress and depression. Our study analyzed the trends in counseling for stress and depression among over two million South Korean adults in 2009-2022, revealing a significant escalation during the pandemic. These findings emphasize the need for mental health policies to support vulnerable groups during the pandemic.

National prevalence of smoking among adolescents at tobacco tax increase and COVID-19 pandemic in South Korea, 2005-2022

Prior research has predominantly focused on the overall effects of the tobacco tax increase and the COVID-19 pandemic on adolescent smoking behavior. However, there is a need to examine both the immediate and sustained associations of these two factors on subgroups of adolescents, employing an interrupted time-series model. We aimed to investigate the immediate and sustained association of tobacco tax increase and the COVID-19 pandemic on adolescent smoking prevalence. This study utilized data from the Korea Youth Risk Behavior Web-Based Survey to analyze the prevalence of current smoking among all participants (CSP) and the prevalence of daily smoking among current smokers (DSP) of Korean adolescents (n = 1,159,995; mean, age 14.99; male 51.5%) over 18 years from 2005 to 2022. The study examined 18-year trends in CSP and DSP among Korean adolescents, emphasizing the influences of the 2015 tobacco tax increase and the COVID-19 pandemic, using β coefficients and their differences (βdiff) from an interrupted time-series ARIMA model. While CSP exhibited a decreasing trend, DSP exhibited an increasing trend. Tobacco tax increase was associated with both the short and long terms in smoking prevalence, however, the short-term association on prevalence (CSP, - 3.076 [95% CI, - 3.707 to - 2.445]; DSP, - 4.112 [95% CI, - 6.488 to - 1.735]) was stronger. The pandemic was associated with an immediate increase in DSP (9.345 [95% CI, 5.285-13.406]). These effects were strongest among adolescents from low economic status and those exposed to familial secondhand smoking. Supportive programs for adolescents in low-income families will help overcome the effects associated with the pandemic. As a tobacco tax increase was associated with a reduction in smoking prevalence, this could be one method to overcome the effects of the pandemic.

National prevalence and trends in food labeling awareness, comprehension, usage, and COVID-19 pandemic-related factors in South Korea, 2014-2022

Although food labeling on food packages is crucial for promoting a healthy diet, limited research has been conducted on how the COVID-19 pandemic (hereinafter "the pandemic") has affected food labeling awareness. Therefore, this study aims to analyze the changes in trends in food labeling awareness, comprehension, and usage in South Korea during the pandemic. We utilized a nationwide, large-scale, and long-term dataset provided by the Korea Community Health Survey (KCHS) from 2014 to 2022 (total = 1,756,847 participants). This allowed the researchers to assess the long-term trends in the prevalence of food labeling awareness, comprehension, and usage. Furthermore, we investigated the factors associated with awareness specifically related to the pandemic. In total, 1,756,847 adults (54.19% women) participated in this study. The upward slope in overall food labeling awareness became less pronounced and even exhibited a downward slope during the pandemic (βdiff - 1.759; 95% CI - 1.874 to - 1.644). The upward slope in food labeling comprehension and usage became more pronounced during the pandemic (comprehension: βdiff 0.535; 95% CI 0.436-0.634; usage: βdiff 0.693; 95% CI 0.601-0.785). The vulnerability factors associated with lower food labeling awareness during the pandemic included older age, male, obesity, residing in rural areas, lower household income, lower educational level, smoking, and increased alcohol consumption. This study analyzed the 9-year trend in the prevalence of food labeling awareness, comprehension, and usage based on nationally representative data of adults in South Korea from 2014 to 2022. Our findings suggest that personalized nutrition strategies are needed to recognize vulnerable groups with risk factors and improve food labeling awareness among Korean adults during the pandemic.

Association between depression, anemia and physical activity using isotemporal substitution analysis

BACKGROUND

Depression is a leading cause of disability and mortality, with estimated number of deaths exceeding 2.2 million worldwide. We examined depression in relation to anemia and physical activity, both of which have an impact on depression mechanisms.

METHODS

This cross-sectional study used data from the Korean National Health and Nutrition Examination Survey, including 18,622 participants. Depression was measured by The Patient Health Questionnaire-9, and physical activity was assessed by the Global Physical Activity Questionnaire. Anemia was defined by World Health Organization criteria for blood hemoglobin levels. Isotemporal substitution model for physical activity was used to assess the effect of replacing sedentary behavior to each intensity level of physical activity. Logistic regression was applied to estimate the association on depression.

RESULTS

Replacing sedentary behavior with moderate or vigorous physical activity was associated with a lower risk of depression in the anemic (OR: 0.875, 95% CI: 0.782-0.978) and non-anemic groups (OR: 0.943, 95% CI: 0.919-0.967). Depression risk was significantly reduced by replacing walking with moderate to vigorous physical activity in both anemic (OR: 0.877, 95% CI: 0.784-0.982) and non-anemic groups (OR: 0.951, 95% CI: 0.927-0.976).

CONCLUSIONS

Moderate to vigorous physical activity had a protective association against depression in both anemic and non-anemic groups. Anemic patients are recommended to perform physical activity for any duration acceptable to them to prevent depression.

National trends in rheumatoid arthritis and osteoarthritis prevalence in South Korea, 1998-2021

Studies on the trends in the prevalence of rheumatoid arthritis (RA) and osteoarthritis (OA) are limited, particularly during the COVID-19 pandemic. This study aimed to analyze the temporal trend of RA and OA in South Korean adults from 1998 to 2021, including the COVID-19 pandemic period. The Korea National Health and Nutrition Examination Survey (KNHANES) data on adults aged ≥ 19 years were analyzed to investigate the prevalence of RA and OA from 1998 to 2021. The prevalence trends were compared by the years, and βdiff (β difference) was calculated. Odds ratios (ORs) were computed for each disease to examine changes in disease prevalence before and during the pandemic in order to determine the impact of the pandemic on disease prevalence. Among 163,221 Korean adults, the prevalence of RA and OA showed a steady decrease from 2005 (RA: from 1.91% in 2005-2007 to 1.55% in 2016-2019 and OA: from 9.75% in 2005-2007 to 8.27% in 2016-2019), but there was a slight increased after the onset of the COVID-19 pandemic (RA: from 1.23% in 2020 to 1.36% in 2021 and OA: from 8.04% in 2020 to 8.27% in 2021). Vulnerable groups, including participants aged ≥ 60 years (versus 19-60 years, ratio of ORs: 1.222; 95% CI 1.011-1.477), urban residents (ratio of ORs: 1.289; 95% CI 1.007-1.650), and participants with higher education level (ratio of ORs: 1.360; 95% CI 1.119-1.653) showed higher ORs of OA, whereas no particularly vulnerable population was observed for RA. Our findings provide an insight into the long-term trends of RA and OA among adult population and highlight a novel perspective on the impact of COVID-19 on disease prevalence.