Association between short- and medium-term exposure to air pollutants and depressive episode using comprehensive air quality index among the population in South Korea.

BACKGROUND: Currently, air pollution is suggested as a risk factor for depressive episodes. Our study aimed to consider multiple air pollutants simultaneously, and continuously evaluate air pollutants using comprehensive air quality index (CAI) with depressive episode risk. METHODS: Using a nationally representative sample survey from South Korea between 2014 and 2020, 20,796 participants who underwent health examination and Patient Depression Questionnaire-9 were included in the study. Six air pollutants (PM10, PM2.5, O3, CO, SO2, NO2) were measured for the analysis. Every air pollutant was standardized by air quality index (AQI) and CAI was calculated for universal representation. Using logistic regression, short- and medium-term exposure by AQI and CAI with the risk of depressive episode was calculated by odds ratio and 95 % confidence interval (CI). Furthermore, consecutive measurements of CAI over 1-month time intervals were evaluated with the risk of depressive episodes. Every analysis was conducted seasonally. RESULTS: There were 950 depressive episodes occurred during the survey. An increase in AQI for short-term exposure (0-30 days) showed higher risk of depressive episode in CO, while medium-term exposure (0-120 days) showed higher risk of depressive episode in CO, SO2, PM2.5, and PM10. During the cold season, the exposure to at least one abnormal CAI within 1-month intervals over 120 days was associated with a 68 % (95 % CI 1.11-2.54) increase in the risk of depressive episode. CONCLUSIONS: Short- and medium-term exposure of air pollution may be associated with an increased risk of depressive episodes, especially for cold season.

COVID-19-related cardiovascular disease risk due to weight gain: a nationwide cohort study.

BACKGROUND: Cardiovascular disease (CVD) is a significant contributor to morbidity and mortality worldwide, with CVD and post-acute COVID-19 associated CVD increasing. It remains unknown whether COVID-19 patients with weight gain are at a high risk for CVD events. Therefore, the primary objective of this study is to investigate the association between weight control and the risk of CVD following COVID-19. METHODS: The study included 2,024,728 adults who participated in two rounds of health screening between 2017 and 2020. The final cohort, which included 70,996 participants in the COVID-19 group and 212,869 participants in the control group. The adjusted hazard ratio of BMI change to CVD risk was calculated using Cox proportional hazards regression. RESULTS: We identified a total of 2869 cases of CVD (861 events for COVID-19 group and 2,008 events for the control group). Compared to individuals with a stable BMI, COVID-19 patients without obesity had an increased risk of CVD (adjusted hazard ratio [aHR] = 2.28; 95% confidence interval [CI], 1.15-4.53; p-value = 0.018). Additionally, non-COVID-19 patients with obesity also exhibited a higher risk of CVD (aHR = 1.58; 95% CI, 1.01-2.47; p-value = 0.046). CONCLUSION: In conclusion, people who gained weight during the pandemic, regardless of their weight category, had a significantly higher risk of CVD associated with COVID-19 compared to those who maintained their weight before the pandemic.

Increased Estimated GFR Is Negatively Associated With the Risk of SARS-CoV-2 Infection and Severe COVID-19 Within Normal to Mildly Decreased Levels: Nested Case-Control Study.

BACKGROUND: While accumulating evidence indicates chronic kidney disease as a risk factor for coronavirus disease 2019 (COVID-19), the association between normal or mildly decreased kidney function and COVID-19 is unaddressed. Here, we have examined the association of an increase in estimated glomerular filtration rate (eGFR) with the incidence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and severe COVID-19 outcomes among patients within normal to mildly decreased kidney function. METHODS: The patients who participated in both health screenings from period I (2017-2018) to II (2019-2020) were enrolled to our study. All participants were categorized into four groups according to the changes in eGFR stage from period I to II: 1) persistently stage G1, 2) from stage G2 to G1, 3) from stage G1 to G2, 4) persistently stage G2. In addition, the changes in eGFR value were defined by subtracting its value of period I from II. Patients were followed up for SARS-CoV-2 infection from January 1, 2021 to any diagnosis of COVID-19 or December 31, 2021, whichever happened first. In addition, those with SARS-CoV-2 infection were followed-up for one month after diagnosis to analyze severe COVID-19. Adjusted odds ratio (aOR) was calculated using multivariable-adjusted logistic regression. RESULTS: We identified 159,427 patients with and 1,804,798 patients without SARS-CoV-2 infection. The risk of SARS-CoV-2 infection decreased when eGFR stage changed from G2 to G1 (aOR, 0.957; 95% confidence interval [CI], 0.938-0.977) and persistently maintained at G1 (aOR, 0.966; 95% CI, 0.943-0.990), compared with the persistently stage G2 group. In addition, the risk showed an inverse relationship with changes in eGFR value, which was depicted by restricted cubic spline curves. For the overall risk of severe COVID-19, the persistently stage G1 showed the lowest risk (aOR, 0.897; 95% CI, 0.827-0.972), followed by those from stage G1 to G2 (aOR, 0.900; 95% CI, 0.828-0.978) and those from stage G2 to G1 (aOR, 0.931; 95% CI, 0.871-0.995), compared with the persistently stage G2 group. CONCLUSION: An increase in eGFR was negatively associated with the risk of SARS-CoV-2 infection and severe COVID-19 among normal or mildly decreased kidney function. For severe COVID-19, maintaining higher baseline eGFR may act as a protective factor against its risk.

Association of weight changes with SARS-CoV-2 infection and severe COVID-19 outcomes: A nationwide retrospective cohort study.

BACKGROUND: Obesity is a risk factor for COVID-19. However, it is unknown whether weight changes can alter this risk. We investigated the association of weight changes with SARS-CoV-2 infection and acute severe COVID-19 outcomes occurring within two months of the infection. METHODS: We used 6.3 million nationwide cohort. The body weight was classified as follows: (1) underweight, body mass index (BMI) < 18.5 kg/m2; (2) normal, BMI 18.5-22.9 kg/m2; (3) overweight, BMI 23-24.9 kg/m2; (4) obese, BMI≥ 25 kg/m2. Weight changes were defined by comparing the classification of body weight during the health screening period I and II. The outcomes were SARS-CoV-2 infection and severe COVID-19 outcomes within two months after the infection. The association was evaluated using multivariable-adjusted logistic regression. The following covariates were adjusted: age, sex, household income, cigarette smoking, alcohol consumption, physical activity, hypertension, diabetes mellitus, dyslipidemia, Charlson comorbidity index score, and dose of all COVID-19 vaccinations prior to SARS-CoV-2 infection. RESULTS: Of the 2119,460 study participants, 184,204 were infected with SARS-CoV-2. Weight gain showed a higher risk of SARS-CoV-2 infection in underweight to normal and normal to overweight groups. Conversely, weight loss showed a lower risk of SARS-CoV-2 infection in normal to underweight, overweight to underweight, overweight to normal, obese to normal, and obese to overweight groups. In addition, weight gain revealed a higher risk of severe COVID-19 outcomes, whereas weight loss showed a lower risk of severe COVID-19 outcomes. CONCLUSION: This study found that weight loss and gain are associated with a lower and higher risk of both SARS-CoV-2 infection and severe COVID-19 outcomes, respectively. Healthy weight management may be beneficial against the risk of COVID-19.

Exercise Frequency Reduction Is Associated With Higher Risk of Infection in Newly Diagnosed Diabetes: A Nationally Representative Cohort Study.

BACKGROUND: Exercise is an important method to control the progression of diabetes. Since diabetes compromises immune function and increases the risk of infectious diseases, we hypothesized that exercise may affect the risk of infection by its immunoprotective effects. However, population-based cohort studies regarding the association between exercise and the risk of infection are limited, especially regarding changes in exercise frequency. The aim of this study was to determine the association between the change in exercise frequency and the risk of infection among patients with newly diagnosed diabetes. METHODS: Data of 10,023 patients with newly diagnosed diabetes were extracted from the Korean National Health Insurance Service-Health Screening Cohort. Self-reported questionnaires for moderate-to-vigorous physical activity (MVPA) were used to classify changes in exercise frequency between two consecutive two-year periods of health screenings (2009-2010 and 2011-2012). The association between changes in exercise frequency and the risk of infection was evaluated using multivariable Cox proportional-hazards regression. RESULTS: Compared with engaging in ≥ 5 times of MVPA/week during both periods, a radical decrease in MVPA (from ≥ 5 times of MVPA/week to physical inactivity) was associated with a higher risk of pneumonia (adjusted hazard ratio [aHR], 1.60; 95% confidence interval [CI], 1.03-2.48) and upper respiratory tract infection (aHR, 1.15; 95% CI, 1.01-1.31). In addition, a reduction of MVPA from ≥ 5 to < 5 times of MVPA/week was associated with a higher risk of pneumonia (aHR, 1.52; 95% CI, 1.02-2.27), whereas the risk of upper respiratory tract infection was not higher. CONCLUSION: Among patients with newly diagnosed diabetes, a reduction in exercise frequency was related to an increase in the risk of pneumonia. For patients with diabetes, a modest level of physical activity may need to be maintained to reduce the risk of pneumonia.

Inverse association between changes in systolic and diastolic blood pressure and risk of depression: A nationally representative cohort study.

BACKGROUND: Depression is one of complex mental disorders with diverse etiological factors but the association between blood pressure (BP) and depression is unknown. We aimed to investigate the association between changes in BP (systolic and diastolic) and incident depression. METHODS: From the National Health Insurance Service-Health Screening Cohort (NHIS-HEALS), 224,192 participants who underwent biennial health screenings from period I (2004-05) and II (2006-07) were included in the study. Systolic BP (SBP) and diastolic BP (DBP) categories were defined as follows: SBP into 5 categories (<90 mmHg, 90 mmHg -119 mmHg, 120 mmHg -129 mmHg, 130 mmHg -139 mmHg, ≥140 mmHg) and DBP into 4 categories (<60 mmHg, 60 mmHg -79 mmHg, 80 mmHg -89 mmHg, ≥90 mmHg). Also, BP levels were classified into 5 groups: normal, elevated BP, stage 1 BP, stage 2 BP, hypotension. Using the Cox proportional hazards regression, changes in SBP and DBP between two screening periods and the risk of depression were calculated by adjusted hazard ratio (aHR) and 95 % confidence interval (CI). RESULTS: There were 17,780 depression events during 1.5 million person-year of follow-up. Compared to the participants with SBP ≥ 140 mmHg or DBP ≥ 90 mmHg from both periods, those who decreased SBP from ≥140 mmHg to 120 mmHg-129 mmHg (aHR 1.13; 95 % CI 1.04-1.24; P = 0.001) and those who decreased DBP from ≥90 mmHg to 60 mmHg-79 mmHg (aHR 1.10; 95 % CI 1.02-1.20; P = 0.020) showed a higher risk of depression, respectively. CONCLUSIONS: Changes in SBP and DBP showed an inverse relationship with depression risk.

Association of Physical Activity With SARS-CoV-2 Infection and Severe Clinical Outcomes Among Patients in South Korea.

Importance: The association of moderate to vigorous physical activity (MVPA) with COVID-19 outcomes is unclear and needs to be investigated. Objective: To identify the association of longitudinal changes in MVPA with SARS-CoV-2 infection and severe COVID-19 outcomes. Design, Setting, and Participants: This nested case-control study used data from 6 396 500 adult patients in South Korean who participated in National Health Insurance Service (NHIS) biennial health screenings from period 1 (2017-2018) to period 2 (2019-2020). Patients were followed from October 8, 2020, until the diagnosis of COVID-19 or December 31, 2021. Exposure: Moderate to vigorous physical activity was measured by self-report on questionnaires during both NHIS health screenings and calculated by adding the frequency (times per week) of each moderate (≥30 minutes per day) and vigorous (≥20 minutes per day) physical activity. Main Outcomes and Measures: The main outcomes were a positive diagnosis of SARS-CoV-2 infection and severe COVID-19 clinical events. Adjusted odds ratio (aORs) and 99% CIs were calculated using multivariable logistic regression analysis. Results: A total of 183 350 patients with COVID-19 (mean [SD] age, 51.9 [13.8] years; female, 89 369 [48.7%]; male, 93 981 [51.3%]) among 2 110 268 participants were identified. For participants with vs without COVID-19, the proportion of MVPA frequency at period 2 was 35.8% vs 35.9% for physically inactive, 18.9% vs 18.9% for 1 to 2 times per week, 17.7% vs 17.7% for 3 to 4 times per week, and 27.5% vs 27.4% for 5 or more times per week. Among unvaccinated, physically inactive patients at period 1, the odds for infection increased when engaged in MVPA 1 to 2 times per week (aOR, 1.08; 99% CI, 1.01-1.15), 3 to 4 times per week (aOR, 1.09; 99% CI, 1.03-1.16), or 5 or more times per week (aOR, 1.10; 99% CI, 1.04-1.17) at period 2. Conversely, among unvaccinated patients with MVPA of 5 or more times per week at period 1, the odds for infection decreased when engaged 1 to 2 times per week (aOR, 0.90; 99% CI, 0.81-0.98) or physically inactive (aOR, 0.80; 99% CI, 0.73-0.87) at period 2. The trend of MVPA and incident infection was mitigated when participants were fully vaccinated. Furthermore, the odds for severe COVID-19 showed significant but limited associations with MVPA. Conclusions and Relevance: The findings of this nested case-control study show a direct association of MVPA with risk of SARS-CoV-2 infection, which was mitigated after completion of the COVID-19 vaccination primary series. In addition, higher levels of MVPA were associated with a lower risk of severe COVID-19 outcomes to limited proportions.

Non-Alcoholic Fatty Liver Disease, Atherosclerosis, and Cardiovascular Disease in Asia.

The prevalence of non-alcoholic fatty liver disease (NAFLD) is estimated to increase to over half of the adult population by 2040 globally. Since the final diagnosis of NAFLD is made by a liver biopsy, several non-invasive approaches have been developed and validated to define NAFLD and evaluate NAFLD-associated diseases. Presently, NAFLD has been identified as an important and independent risk factor for developing several extrahepatic diseases, including atherosclerosis, cardiovascular disease (CVD), diabetes, and dementia. This review discusses current findings of up-to-date literature regarding the effects of NAFLD on the risk of atherosclerosis and CVD in Asia along with potential underlying biological mechanisms and therapeutic approaches to lower the NAFLD-related CVD risk. We further focus on the difference between NAFLD and metabolic dysfunction-associated fatty liver disease (MAFLD) on the risk of CVD and its implication by comparing the risk of NAFLD and MAFLD.

Poorer outcomes following COVID-19 infection for patients with depression: A cohort analysis in South Korea.

Introduction: It remains unknown whether patients with pre-existing depressive conditions are at high risk of severe COVID-19. Therefore, this study aims to investigate the association between patients with pre-existing depressive conditions and severe COVID-19. Method: This study is part of the Korea Disease Control and Prevention Agency-COVID19-National Health Insurance Service cohort study of an ongoing large-scale health screening survey of adults 18 years and older residing in South Korea. Pre-existing depression status was measured from 552,860 patients who participated in a biennial health screening from 2019 to 2020. Finally, 29,106 confirmed COVID-19 patients were enrolled and followed up to track any severe clinical events within 1 month of their diagnosis date. Adjusted odds ratio (aOR) and 95% confidence interval (CI) were calculated using multivariate-adjusted logistic regression analysis. Results: We identified 2868 COVID-19 patients with severe clinical events and 26,238 COVID-19 patients without severe clinical events. The moderate-to-severe depressive symptoms group showed an elevated odds of severe outcomes of COVID-19 (aOR, 1.46; 95% CI, 1.25-1.72), including those without vaccination (aOR, 1.32; 95% CI, 1.08-1.61) and those with complete vaccination (aOR, 1.76; 95% CI, 1.18-2.63). In addition, those who were diagnosed with depression along with depressive symptoms at the health screening revealed an increased risk of severe outcomes of COVID-19 (aOR, 2.22; 95% CI, 1.22-4.05). Conclusion: Moderate-to-severe depressive symptoms were associated with higher odds of severe COVID-19 events in both no and complete vaccination groups. Participants with depressive symptoms may be at higher risk of severe outcomes of COVID-19.

Development and validation of a nonalcoholic fatty liver disease-based self-diagnosis tool for diabetes.

Background: Prediction of type 2 diabetes mellitus (DM) has been studied widely. However, a hospital visit was necessary to apply previous prediction models for the evaluation of DM. This study was conducted to develop and validate a hospital visit-free self-diagnosis tool for DM. Methods: Participants who underwent health screening between 2017-2018 (n=7,519; training cohort) and 2019-2020 (n=7,564; validation cohort) were extracted from the Korea National Health and Nutrition Examination Survey (KNHANES). DM was defined as doctor-diagnosed DM in a questionnaire. Logistic regression was used to determine independent predictors for DM, and a multivariable logistic regression-based nomogram was developed for the prediction of DM, which was validated in a cohort consisting of an independent population. The presence of nonalcoholic fatty liver disease (NAFLD) was operationally defined using the KNHANES-NAFLD score. Results: Age, sex, waist circumference, systolic blood pressure, total cholesterol, triglyceride, aspartate aminotransferase, blood urea nitrogen, urinary protein, urinary glucose, and NAFLD were identified as independent predictors for DM. After excluding laboratory variables that require laboratory tests, a simplified multivariable model was conducted based on hospital visit-free variables, including age, sex, waist circumference, systolic blood pressure, and NAFLD. The full and simplified prediction models for DM were presented as nomograms. In the independent validation cohort, the full and simplified DM prediction models were validated with an area under the curve values of 0.903 and 0.824 from the receiver operating characteristic curves, respectively. Conclusions: Involvement of NAFLD has allowed satisfactory prediction of DM without laboratory tests that require a hospital visit. The developed model may be promising in terms of early diagnosis of DM among individuals without hospital visits and may reduce the socioeconomic burden of DM in the real-world, which awaits future prospective trials to confirm.

Health-Screening-Based Chronic Obstructive Pulmonary Disease and Its Effect on Cardiovascular Disease Risk.

Chronic obstructive pulmonary disease (COPD) is considered a major cause of death worldwide, and various studies have been conducted for its early diagnosis. Our work developed a scoring system by predicting and validating COPD and performed predictive model implementations. Participants who underwent a health screening between 2017 and 2020 were extracted from the Korea National Health and Nutrition Examination Survey (KNHANES) database. COPD individuals were defined as aged 40 years or older with prebronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC < 0.7). The logistic regression model was performed, and the C-index was used for variable selection. Receiver operating characteristic (ROC) curves with area under the curve (AUC) values were generated for evaluation. Age, sex, waist circumference and diastolic blood pressure were used to predict COPD and to develop a COPD score based on a multivariable model. A simplified model for COPD was validated with an AUC value of 0.780 from the ROC curves. In addition, we evaluated the association of the derived score with cardiovascular disease (CVD). COPD scores showed significant performance in COPD prediction. The developed score also showed a good effect on the diagnostic ability for CVD risk. In the future, studies comparing the diagnostic accuracy of the derived scores with standard diagnostic tests are needed.