Changes in exercise frequency and cardiovascular outcomes in older adults.

AIMS: Little is known about the association of changes in moderate to vigorous physical activity (MVPA) level with cardiovascular disease (CVD), especially in older adults whose ability to engage in frequent MVPA naturally wanes as they age. We aimed to examine the association of changes in MVPA and CVD in older adults. METHODS AND RESULTS: In a nationwide cohort study of older adults aged 60 years or older, we identified more than 1.1 million subjects without previous history of CVD at baseline who underwent two consecutive national health screening from 2009 to 2012. We prospectively assessed the risk of CVD occurred between 2013 and 2016 according to changes in frequency of MVPA by initial MVPA status. Compared to those who were continuously physically inactive, those who increased their frequency of MVPA from physically inactive to 1-2 times per week [0.7/1000 person-years (PY) decrease in incidence rate (IR); adjusted hazard ratio (aHR) 0.95; 95% confidence interval (CI) 0.92-0.99], 3-4 times per week (1.5/1000 PY decrease in IR; aHR 0.89; 95% CI 0.84-0.94), ≥5 times per week (0.4/1000 PY decrease in IR; aHR 0.91; 95% CI 0.85-0.97) had a significantly reduced risk for total CVD (P for trend <0.001). Older adults who became physically inactive from engaging in more than 1-2 times of MVPA per week had a higher CVD risk compared to those who maintained their frequency of MVPA. CONCLUSION: Among older adults, engaging in higher frequency of MVPA or maintaining MVPA level was associated with reduced risk of CVD.

Effects of abdominal obesity on the association between air pollution and kidney function.

OBJECTIVES: This study aimed to evaluate the associations between ambient air pollutants, obesity, and kidney function. SUBJECTS/METHODS: We enrolled 3345 people who had undergone health checkups at Seoul National University Hospital. We recorded the annual average concentrations of ambient air pollutants, including particulate matter with an aerodynamic diameter of ≤10 µm (PM10), nitrogen dioxide (NO2), sulfur dioxide (SO2), and carbon monoxide (CO), in each subject's residential area. Various obesity traits, such as body mass index, waist circumference, and visceral and subcutaneous adipose tissue areas, were measured by quantified computerized tomography (CT), and kidney function was assessed in relation to estimated glomerular filtration rate as an indicator of kidney function. RESULTS: High PM10, NO2, SO2, and CO concentrations were significantly associated with decreased kidney function (ß = -2.39 and standard error = 0.32, -1.00 and 0.31, -1.23 and 0.28, and -1.32 and 0.29, respectively), and with the prevalence of chronic kidney disease (CKD). The association between air pollutant concentrations and decreased kidney function, including CKD, was stronger among those with high abdominal adiposity, as defined by CT measurement. For example, the association between increased concentrations of air pollutants and the prevalence of CKD was stronger in the group with greater visceral adiposity than in the group with less visceral adiposity (aORs = 1.29 vs 1.16 for PM10, 1.42 vs 1.21 for SO2, and 1.27 vs 1.11 for CO). CONCLUSIONS: Long-term exposure to higher concentrations of air pollutants was unfavorably associated with kidney function and CKD prevalence, especially in people with abdominal obesity. This may indicate a high susceptibility to air pollutants in obese people.

Association between social trust and the risk of cardiovascular disease in older adults in Korea: a nationwide retrospective cohort study.

BACKGROUND: Although social capital has been shown to be one of the important social determinants of health, the association between social trust and the risk of cardiovascular disease (CVD) is not clear yet. We aimed to investigate the association of social trust with CVD risk using a large Korean population based data. METHODS: The data of this study was derived from the Korean National Health Insurance Service database. Community-level social trust was determined from the Korean Community Health Survey. The study population consisted of 2,156,829 participants. According to social trust index measured in the area of residence during 2011, participants were followed-up from 1 January 2012 to 31 December 2016. Multivariate Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for CVD risk according to quintiles of social trust. RESULTS: Compared to participants with the lowest quintile of social trust, those within the highest quintile had lower risk for CVD (aHR 0.91, 95% CI = 0.89 to 0.93), CHD (aHR 0.92, 95% CI = 0.89 to 0.95), and stroke (aHR 0.90, 95% CI = 0.87 to 0.93). The risk-reducing association of high social trust on CVD risk was preserved after additional adjustments for lifestyle behaviors including smoking, alcohol consumption, and physical activity. CONCLUSION: Higher social trust was associated with reduced risk of CVD even after considering lifestyle behaviors. Social trust in a community level is an important determinant of CVD and enhancing social trust may lead to reduced risk of CVD.

Association of community level social trust and reciprocity with mortality: a retrospective cohort study.

BACKGROUND: Whether community level social capital is associated with mortality within an Asian population is yet unclear. METHODS: The study population was derived from the Korean National Health Insurance Service-National Sample Cohort. A total of 636,055 participants were followed-up during 2012-2013 for deaths from all causes, cardiovascular disease (CVD), cancer, and other causes. Community level social trust and reciprocity at the administrative district level were derived from the Korean Community Health Survey. Cox proportional hazards regression was used to determine the adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for mortality according to levels of community level social trust and reciprocity. RESULTS: Compared to participants who reside in areas within the lower half of community level social trust, those who reside in areas within the upper half had lower risk of death from all causes (aHR 0.84, 95% CI 0.78-0.89), CVD (aHR 0.82, 95% CI 0.67-0.99), and cancer (aHR 0.85, 95% CI 0.73-0.98). Similarly, residing in areas in the upper half of community level social reciprocity was associated with reduced risk for all-cause mortality (aHR 0.80, 95% CI 0.75-0.86). The protective association of high community level social trust and reciprocity on mortality remained after additional adjustments for smoking, alcohol intake, and physical activity. CONCLUSIONS: Residing in areas with high community level social trust and reciprocity may be associated with better population health status.

Higher Physical Activity is Associated with Reduced Lower Urinary Tract Symptoms in Korean Men.

PURPOSE: Identifying and managing risk factors for lower urinary tract symptoms (LUTS) is crucial because it impacts the quality of life of elderly individuals. Lifestyle factors, including physical activity (PA), and their relationship with LUTS have not been well studied. This objective of this study was to investigate the association between PA and LUTS. MATERIALS AND METHODS: A total of 7,296 men were included in this cross-sectional study. PA was quantified in metabolic equivalent (MET)-hours per week, and LUTS severity was assessed using the international prostate symptom score. Logistic regression was used to analyze the association between PA and LUTS, including voiding and storage symptoms. RESULTS: The average age of the participants was 57.8 years, and the prevalence of LUTS was 41.3%. After adjusting for potential confounders, PA was inversely associated with the prevalence and severity of moderate-to-severe LUTS, showing a dose-response pattern (all p for trend <0.01). Compared to the minimal activity group, which engaged in <5 MET-hours per week of PA, the odds ratios for moderate to severe LUTS were 0.83 (95% confidence interval [CI]: 0.72-0.97) for men engaging in 15-30 MET-hours per week, 0.82 (95% CI: 0.71-0.95) for 30-60 MET-hours per week, and 0.72 (95% CI: 0.62-0.84) for ≥60 MET-hours per week. The possible protective effect of PA was still observed in the additional analysis for voiding and storage symptoms showing the same dose-response pattern (all p for trend <0.01). CONCLUSIONS: A higher PA level was associated with a lower prevalence and severity of total, voiding, and storage LUTS in a dose-dependent manner in Korean men.

Socio-demographic, psychological, and experiential predictors of COVID-19 vaccine hesitancy in South Korea, October-December 2020.

Vaccine hesitancy is the primary barrier to controlling the COVID-19 pandemic in South Korea. We used logistic multivariate regression modeling to investigate (1) the prevalence and reasons for COVID-19 vaccine hesitancy, (2) sub-groups that had higher rates of vaccine hesitancy, and (3) vaccine hesitancy predictors. We used a national survey of representatively sampled households (n = 13,021 adults) from October to December 2020. A self-report questionnaire asked about vaccination intention and reasons for hesitancy and gathered data on socio-demographic, demographic, psychological, and experiential factors. Our study indicated that 39.8% of the participants answered that they hesitated or refused to be vaccinated. The most common reason for vaccine hesitancy was a lack of confidence in the COVID-19 vaccine (77.9%). Less or no fear of COVID-19 (OR = 2.08, 95% CI = 1.92-2.26; OR = 1.79, 95% CI = 1.54-2.08), unstable job status (OR = 1.42, 95% CI = 1.18-1.70), decreased family income (OR = 1.40, 95% CI = 1.21-1.61), and worsening health status (OR = 1.38, 95% CI = 1.13-1.68) were predictors of vaccine hesitancy. Younger age, no religious affiliation, political conservatism, and lower family income were also significantly associated with vaccine hesitancy. Effective health communication and policies need to consider the target subgroup population and predictors of vaccine hesitancy to attain herd immunity at an early stage.

Association between long-term air pollution exposure and insulin resistance independent of abdominal adiposity in Korean adults.

Significant associations between air pollution (AP) and insulin resistance (IR) have been reported in limited populations or certain patient groups, but few studies have addressed this association in the general population, especially in Asians. Although abdominal fat is a major contributor to IR, previous studies have not fully controlled for its effect in the association between AP and IR. We investigated the association between exposure to AP and IR in Korean adults in the general population and whether this association is maintained even after controlling for the effects of abdominal fat, particularly visceral fat. This was a cross-sectional study. Data were obtained for Korean adults who participated in screening health checkups at Seoul National University Health Examination Center from 2006 to 2014. A total of 4251 men and women aged 22-84 years were included. IR was represented by the homeostasis model assessment of insulin resistance (HOMA-IR). Adiposity traits such as visceral adipose tissue (VAT) and subcutaneous adipose tissue areas were measured by computed tomography. We assessed the annual mean concentrations of air pollutants, including particulate matter with an aerodynamic diameter of 10 µm or less (PM10), nitrogen dioxide, sulfur dioxide, and carbon monoxide. HOMA-IR was significantly associated with increased annual mean exposure to PM10 in both men (ß = 0.15; 95% CI 0.09, 0.22) and women (ß = 0.16; 95% CI 0.09, 0.23), and these associations were maintained even after controlling for VAT area (both p < 0.05). The adjusted mean HOMA-IR increased gradually with the level of long-term PM10 exposure (low, intermediate, and high exposure) (all p for trend < 0.001) in the subgroup analysis. After adjusting for possible confounding factors, including VAT area, the annual mean exposure to PM10 was significantly associated with the presence of IR in both men (OR 1.18; 95% CI 1.03, 1.35) and women (OR 1.44; 95% CI 1.18, 1.76). Other air pollutants, such as NO2, SO2 and CO, did not show any significant associations with HOMA-IR or the presence of IR. Persistent exposure to PM10 is the main independent risk factor for IR and exhibits a dose-dependent association regardless of visceral fatness in both men and women.

Factors related to the success of smoking cessation: A retrospective cohort study in Korea.

INTRODUCTION: Every year, at least half of the smokers in South Korea attempt to quit smoking. However, the Korean smoking rate remains still high among OECD countries. This study aimed to identify the factors that influence the success of smoking cessation efforts. METHODS: The study included 1395 smokers, who participated in a 12-week program comprising doctor counseling and pharmacological treatment (i.e. varenicline), conducted at smoking cessation clinics in two general hospitals from 2015 to 2019. The participants responded to a survey questionnaire inquiring about their smoking behaviors at the first visit to the clinic. After completing the program, they were asked whether they succeeded in smoking cessation. Based on participants' reported success or failure, multivariable logistic regression analyses were conducted to obtain adjusted odds ratios (AORs) and 95% confidence intervals (CIs) for factors related to smoking cessation success. RESULTS: Following the 12-week program, 39.6% of the participants (n=553) succeeded in smoking cessation. Lower rates of nicotine dependence (AOR=0.73; 95% Cl: 0.54-0.98) and lower total amounts of smoking (AOR=0.67; 95% Cl: 0.47-0.95) were significantly associated with higher success rates in smoking cessation. In addition, smokers who participated in the program for at least 8 weeks (AOR=7.16; 95% Cl: 5.57-9.20) and smokers who had hypertension (AOR=1.40; 95% Cl: 1.07-1.85) or a cardiovascular disease (AOR=1.68; 95% Cl: 1.03-2.75) achieved higher success rates. CONCLUSIONS: Smokers' success in smoking cessation was influenced by the period of visits to the smoking cessation clinic, the severity of nicotine dependence, and the presence of a cardiovascular disease including hypertension. Using these factors, smoking cessation strategy may be improved and personalized for individuals.

Possible aerosol transmission of COVID-19 associated with an outbreak in an apartment in Seoul, South Korea, 2020.

BACKGROUND: Scientists have strongly implied that aerosols could be the plausible cause of coronavirus disease-2019 (COVID-19) transmission; however, aerosol transmission remains controversial. THE STUDY: We investigated the epidemiological relationship among infected cases on a recent cluster infection of COVID-19 in an apartment building in Seoul, South Korea. All infected cases were found along two vertical lines of the building, and each line was connected through a single air duct in the bathroom for natural ventilation. Our investigation found no other possible contact between the cases than the airborne infection through a single air duct in the bathroom. The virus from the first infected case can be spread to upstairs and downstairs through the air duct by the (reverse) stack effect, which explains the air movement in a vertical shaft. CONCLUSIONS: This study suggests aerosol transmission, particularly indoors with insufficient ventilation, which is underappreciated.

Association between weight change over a period of 4 years and mortality in Korean older adults.

AIM: This study aimed to evaluate the association between weight change and mortality in Korean older adults. METHODS: We collected data pertaining to National Screening Program participants aged ≥65 years from the Korean National Health Insurance Corporation records during 2005-2011. To this data, we included mortality data, such as the date of death, of these patients (up to and including 2017) from Statistics Korea. We defined weight change as a difference in bodyweight measured in the National Screening Program over a period of 4 years. Cox proportional hazards models were used to evaluate the association between weight change and mortality. RESULTS: The study population consisted of 1 100 256 participants, and a total of 46 415 deaths were observed during a mean follow-up period of 3.2 ± 0.8 years (maximum 5.0 years). For 3 531 585 person-year follow up, the mortality rate for stable weight was 10.79 per 1000 person-years (PY). Weight loss increased the mortality rate by 68%, whereas weight gain increased the rate by 10% compared with stable weight (weight loss: mortality rate 20.28 per 1000 PY, adjusted hazard ratio 1.68, 95% confidence interval 1.65-1.72; weight gain: mortality rate 12.86 per 1000 PY, adjusted hazard ratio 1.10, 95% confidence interval 1.07-1.13). However, in subgroup analysis, for participants who were underweight at baseline, current cigarette smokers or heavy alcohol drinkers, weight gain did not increase the mortality rate. CONCLUSIONS: In Korean older adults, regardless of the risk factors, both weight loss and weight gain increased the mortality rate compared with stable weight. Geriatr Gerontol Int 2020; 20: 474-481.

Ambient air pollution exposure and obesity-related traits in Korean adults.

PURPOSE: Although some studies have tried to determine the impact of long-term air pollution exposure on obesity, they have mainly focused on body mass index (BMI) and the results are inconsistent. Therefore, we investigated the association of annual ambient air pollution exposure with various obesity traits, including computed tomography-measured abdominal fatness, in a large Korean adult population. PATIENTS AND METHODS: A total of 5,114 participants who underwent routine health check-ups at Seoul National University Hospital were included in the analysis. We calculated the annual average concentrations of ambient air pollutants, such as particulate matter ≤10 µm in diameter (PM10) and nitrogen dioxide (NO2), using the individual's zip code. Obesity-related indicators included the BMI, waist circumference (WC), percent body fat (PBF), total adipose tissue (TAT), visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT). RESULTS: The mean age of the population was 53.5 and 70.9% were men. The mean annual concentrations of PM10 and NO2 were 49.4 µg/m3 and 30.3 ppb, respectively. In the full covariates model, adjusted for demographic and clinical variables, interquartile range increase in annual average concentration of PM10 and NO2 was not associated with any obesity-related phenotypes including BMI, WC, PBF, TAT, VAT, and SAT (all P>0.05). Likewise, no significant association between air pollutants and obesity-related traits was observed in any subgroups, stratified by sex and age (all P>0.05). CONCLUSION: Annual exposure to ambient air pollution is not associated with any obesity-related traits in Korean adults.

Effects of abdominal visceral fat compared with those of subcutaneous fat on the association between PM10 and hypertension in Korean men: A cross-sectional study.

We assessed whether visceral adipose tissue (VAT) compared with subcutaneous adipose tissue (SAT) has modifying effects on the cross-sectional association between ambient air pollution and hypertension in Korean men. This study included 1,417 adult men who visited a health checkup center. Abdominal fat depots were measured by computed tomography, and we used the annual average concentrations of ambient air pollutants such as particulate matter with an aerodynamic diameter of ≤10 µm (PM10), nitrogen dioxide, sulfur dioxide, and carbon monoxide (CO). The annual mean concentrations of PM10 (odds ratio [OR] = 1.30; 95% confidence interval [CI] = 1.12-1.52) and CO (OR = 1.20; 95% CI = 1.03-1.39) showed a positive association with hypertension. In particular, modifying effects on hypertension were found between PM10 and VAT-related traits such as VAT and visceral-to-subcutaneous fat ratio (VSR). The association between PM10 and hypertension was much stronger in the high-VAT (OR = 1.74; 95% CI = 1.12-2.71) and high-VSR groups (OR = 1.53; 95% CI = 1.23-1.91). However, the strength of association across levels of SAT was not observed (Pint = 0.4615). In conclusion, we found that association between PM10 exposure and hypertension is different by abdominal fat distribution.

The development of a community-based medical education program in Korea.

PURPOSE: The introduction of community-based medical education would help improve the quality of primary care. This paper suggests learning objectives and an educational program for community-based medical education. METHODS: The educational program was developed in a 1-day consensus workshop. Twenty experts, including faculty members from family medicine department of a college of medicine in Seoul and community-based preceptors, participated in the program. A needs-assessment survey was conducted among community-based preceptors before the workshop. Through this workshop, we derived learning objectives and a standardized curriculum for community-based medical education. RESULTS: In the questionnaire before the workshop, community-based preceptors voiced concerns over the program's potential costs and the time required for teaching. The learning objectives and educational programs derived from the workshop's consensus were consistent with the characteristics of the primary care. Based on the results of this workshop, the joint expert team developed a standard educational program on two core topics: clinical teaching and mentoring. CONCLUSION: From this curriculum development process, participants could construct a more standardized curriculum for community-based medical education. Future studies are needed to evaluate the long-term outcomes of these educational programs, such as the learners' satisfaction and achievement.

Prevalence of depression and correlates of depressive symptoms for residents in the urban part of Jeju Island, Korea.

AIMS: This study examined the prevalence of depression and depressive symptoms, and the correlates of depressive symptoms, and proposes some methods for reducing risk of depression in residents of the urban part of Jeju Island in Korea. METHODS: In all, 1050 residents were selected using multiphasic cluster sampling to represent each district. Of the 981 respondents, 413 were men and 568 were women. The Center for Epidemiologic Studies Depression Scale (CES-D) was used to evaluate depression (CES-D score over 25) and depressive symptoms (CES-D score over 21). Multiple logistic regression analysis was performed for comparisons. RESULTS: The prevalence of depression in males and females was comparable, at 9.47 and 11.36%, respectively. The prevalence of depressive symptoms in men was 15.01%, while in women the level rose to 18.37%. Those with high self-assessed level of stress scores were significantly more likely to have depressive symptoms than those with low self-assessed level of stress scores (odds ratio (OR) = 5.73 (95% confidence interval (95% CI), 1.29-25.36)). Residents at high risk of problem drinking (CAGE score over 3) were significantly more likely to have depressive symptoms than those with a CAGE score under 1 (OR = 3.43 95% CI, 1.77-6.66). Respondents who slept poorly had more depressive symptoms than respondents who slept well (OR = 2.11 95% CI, 1.37-3.23). Females were significantly more likely to have more depressive symptoms than males (OR = 1.70 95% CI, 1.08-2.68). CONCLUSIONS: The prevalence of depression and depressive symptoms in urban Jeju Island is similar to that in a nation-wide sample. By providing intensive mental health services to those who have high stress levels, problem drinking, and poor health behavior, early detection of depressive symptoms in the community will be important for improving general health status.

Association between Living Arrangements and Influenza Vaccination Rates among Elderly South Korean People: The Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-2).

BACKGROUND: This study aimed to investigate the association between living arrangements and influenza vaccination among elderly South Korean subjects. METHODS: We used data from the fifth Korean National Health and Nutrition Examination Survey. Participants older than 65 years were included and categorized into 4 groups according to the type of living arrangement as follows: (1) living alone group; (2) living with a spouse group; (3) living with offspring (without spouse) group; and (4) living with other family members group. A total of 1,435 participants were included in this cross-sectional analysis. RESULTS: A lower vaccination rate was observed in the living with offspring (without spouse) group, whereas the living with a spouse group had higher rates of both seasonal and H1N1 influenza vaccination. After adjusting for age, sex, region, education level, income level, and number of comorbidities, the living with offspring (without spouse) group had a higher H1N1 vaccination non-receipt rate than the living alone group (odds ratio, 2.03; 95% confidence interval, 1.08-3.82). CONCLUSION: Influenza vaccination rates differed according to the type of living arrangement. Particularly, those living with offspring (without spouse) had the lowest H1N1 influenza vaccination rate compared to those with other living arrangements, and this difference was significant. Interventions to improve influenza vaccination coverage should target not only elderly persons who live alone, but also those living with offspring.