Age-specific effects of ozone on pneumonia in Korean children and adolescents: a nationwide time-series study / 한국역학회지

OBJECTIVES@#The aim of this study was to estimate the age-specific effects of 8-hour maximum ozone levels on pneumonia in children and adolescents. @*METHODS@#We performed quasi-Poisson regression analyses for individuals of 0-4 years, 5-9 years, 10-14 years, and 15-19 years of age using nationwide time-series data from the Korea (2011-2015). We constructed distributed lag linear models employing a generalized difference-in-differences method and controlling for other air pollutants. @*RESULTS@#A 10.0-parts per billion increase in 8-hour maximum ozone levels was associated with a higher risk of hospital admissions due to pneumonia at 0-4 (relative risk [RR], 1.02; 95% confidence interval [CI], 1.01 to 1.03) and 5-9 years of age (RR, 1.06; 95% CI, 1.04 to 1.08), but not at 10-14 (RR, 1.01; 95% CI, 0.98 to 1.04) or 15-19 years of age (RR, 1.01; 95% CI, 0.97 to 1.06). The association between ozone and hospital admissions due to pneumonia was stronger in cool seasons (from November to April) than in warm seasons (from May to October), but was similar between boys and girls. @*CONCLUSIONS@#Short-term exposure to ozone was associated with a higher risk of pneumonia at 0-4 years and 5-9 years of age, but not at 10-14 years or 15-19 years of age. Our findings can help identify vulnerable periods, determine the target populations for public health interventions, and establish air pollution standards.

Short- and Long-Term Exposure to Particulate Matter and Pulse Wave Velocity / 가정의학회지

Background@#In hemodialysis patients, brachial-ankle pulse wave velocity (baPWV) levels are affected by particulate matter with an aerodynamic diameter of 10 μm or less (PM10). We conducted this study to determine whether there is an association between short- and long-term PM10 exposure and baPWV in apparently healthy adults aged 40 years and older. @*Methods@#A total of 1,628 subjects who underwent health examinations between 2006 and 2009 were included in the study. On the basis of the day of medical screening, the 1–3-day and 365-day moving averages of PM10 concentrations were used to evaluate the association between short- and long-term exposure to PM10 and high baPWV (≥the third quartile of baPWV, 1,534 cm/s) using logistic regression models. Additional subgroup analyses were conducted according to age, sex, obesity (body mass index ≥25.0 kg/m2), and comorbidities such as metabolic syndrome. @*Results@#No statistically significant associations were identified between short-term and long-term exposure to PM10 and baPWV in any of the subjects and subgroups. A 10-μg/m3 increase in the 2-day moving average of PM10 exposure was marginally associated with high baPWV in non-obese subjects (odds ratio, 1.059; P=0.058). This association in non-obese subjects was significantly different from that in obese subjects (P=0.038). @*Conclusion@#This study did not show statistically significant associations between short-term and long-term exposure to PM10 and baPWV in apparently healthy subjects. With short-term exposure to PM10, non-obese subjects showed a marginally unfavorable association with baPWV. Further studies are necessary to validate and elucidate the mechanism underlying the effect of PM10 on baPWV.

Associations Between Thyroid Hormone Levels and Urinary Concentrations of Bisphenol A, F, and S in 6-Year-old Children in Korea / 예방의학회지

Objectives@#Bisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children. @*Methods@#Prenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations. @*Results@#The associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (-1.94%; 95% confidence interval, -3.82 to -0.03) were associated with higher urinary BPF concentrations in girls only. @*Conclusions@#Our findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only.

Short- and Long-Term Exposure to Particulate Matter and Pulse Wave Velocity / 가정의학회지

Background@#In hemodialysis patients, brachial-ankle pulse wave velocity (baPWV) levels are affected by particulate matter with an aerodynamic diameter of 10 μm or less (PM10). We conducted this study to determine whether there is an association between short- and long-term PM10 exposure and baPWV in apparently healthy adults aged 40 years and older. @*Methods@#A total of 1,628 subjects who underwent health examinations between 2006 and 2009 were included in the study. On the basis of the day of medical screening, the 1–3-day and 365-day moving averages of PM10 concentrations were used to evaluate the association between short- and long-term exposure to PM10 and high baPWV (≥the third quartile of baPWV, 1,534 cm/s) using logistic regression models. Additional subgroup analyses were conducted according to age, sex, obesity (body mass index ≥25.0 kg/m2), and comorbidities such as metabolic syndrome. @*Results@#No statistically significant associations were identified between short-term and long-term exposure to PM10 and baPWV in any of the subjects and subgroups. A 10-μg/m3 increase in the 2-day moving average of PM10 exposure was marginally associated with high baPWV in non-obese subjects (odds ratio, 1.059; P=0.058). This association in non-obese subjects was significantly different from that in obese subjects (P=0.038). @*Conclusion@#This study did not show statistically significant associations between short-term and long-term exposure to PM10 and baPWV in apparently healthy subjects. With short-term exposure to PM10, non-obese subjects showed a marginally unfavorable association with baPWV. Further studies are necessary to validate and elucidate the mechanism underlying the effect of PM10 on baPWV.

The Effect of Prenatal Cadmium Exposure on Attention-deficit/Hyperactivity Disorder in 6-Year-old Children in Korea / 예방의학회지

Objectives@#Prenatal cadmium (Cd) exposure may be associated with attention-deficit/hyperactivity disorder (ADHD) in children. Therefore, the objective of this study was to examine the relationship between Cd exposure during gestation and ADHD at 6 years of age. @*Methods@#As part of an ongoing cohort study (the Environment and Development of Children study), 479 mother-child pairs from Seoul, Korea were included for analysis between 2008 and 2011. The whole blood concentration of Cd was analyzed using atomic absorption spectrophotometry. The parents were surveyed about ADHD behaviors in their children at age 6. Multivariable linear regression models were used to investigate the relationship between prenatal exposure to Cd and ADHD at 6 years of age. @*Results@#Increased prenatal Cd concentrations were associated with increased scores for ADHD for girls, but not for boys, at age 6. A 2-fold increase in the prenatal Cd level was significantly associated with a 22.3% (95% confidence interval, 11.6 to 34.1) increase in ADHD in girls at 6 years of age, as indicated by the linear regression model. @*Conclusions@#Our results identified significant associations between prenatal Cd exposure and ADHD scores in 6-year-old girls.

Association Between Air Conditioning Use and Self-reported Symptoms During the 2018 Heat Wave in Korea / 예방의학회지

Objectives@#The purpose of this study was to investigate the health effects of air conditioning use during the 2018 heat wave in Korea, included the highest temperature ever recorded in the nation. @*Methods@#The participants in this study were 1000 adults aged 19 years and older recruited from across Korea. The participants were asked about their experience of symptoms of various diseases, disruptions of their daily lives, and use of air conditioning during the heat wave. The associations between air conditioning use during the heat wave and health outcomes were analyzed using the chi-square test and multiple logistic regression models. @*Results@#Among participants who lacked air conditioning in the main space where they spent time outside the home, 33.9%, 8.1%, 43.5%, and 19.4% experienced symptoms of heat-related, cardiovascular, nervous system diseases, and air-conditioningitis, respectively. In comparison, participants who did have air conditioning outside the home experienced the same symptoms at proportions of 21.0%, 1.9%, 26.8%, and 34.2%, respectively (p=0.027, 0.007, 0.007, and 0.023, respectively). Among participants who had no air conditioner at home, 10.0% were absent from school or work due to the heat wave. In contrast, among participants who had an air conditioner at home, only 3.7% were absent as a result of the heat wave (p=0.007). @*Conclusions@#When air conditioning was not used at home or in the main space where participants spent time outside the home during the 2018 heat wave, adverse health effects were more prevalent, but the risk of air-conditioningitis was reduced.

Prominent seasonal variation in pulmonary embolism than deep vein thrombosis incidence: a Korean venous thrombosis epidemiology study

Background/Aims@#Seasonal variation is an environmental factor proposed to affect the incidence of venous thromboembolism (VTE). However, VTE seasonal variation is not well studied in Asian populations, which have different genetic determinants of VTE compared to Westerners. The present study aimed at investigating seasonal variation of VTE occurrence and the effect of various demographic factors (i.e., age, sex, and co-morbidities) on variation. @*Methods@#VTE seasonal variation was evaluated in 59,626 index cases (from January 2009 to December 2013) in the Korean Health Insurance Review and Assessment Service database. We quantified and compared VTE occurrence across four seasons, and additionally assessed monthly through a chronobiological analysis. @*Results@#VTE incidence varied both seasonally and monthly, with new cases peaking in the winter (January and February) and the lowest incidence in the summer (August and September). After adjusting for sex, age, type of VTE, and combined cancer diagnosis, winter remained a significant independent factor driving VTE incidence. Additionally, seasonal variation was prominent in patients aged 60 years or older and in patients with pulmonary embolism, but not so prominent in patients of aged less than 60 years and patients with deep vein thrombosis. @*Conclusions@#Seasonal variation was a weak but independent contributor to VTE incidence in a Korean population diagnosed from 2009 to 2013, especially in those individuals with old age or suffering from a pulmonary embolism.

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND@#Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.@*METHODS@#Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.@*RESULTS@#After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.@*CONCLUSION@#Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND: Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.METHODS: Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.RESULTS: After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.CONCLUSION: Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Effects of Particulate Respirator Use on Cardiopulmonary Function in Elderly Women: a Quasi-Experimental Study

BACKGROUND@#Individual particulate respirator use may offer protection against exposure to particulate matter < 2.5 µm in diameter (PM(2.5)). Among elderly Korean women, we explored individual particulate respirator use and cardiopulmonary function.@*METHODS@#Recruited in Seoul, Korea, 21 elderly, non-smoking women wore particulate respirators for six consecutive days (exlcuding time spent eating, sleeping, and bathing). We measured resting blood pressure before, during, and after respirator use and recorded systolic and diastolic blood pressure, mean arterial blood pressure, pulse pressure, and lung function. We also measured 12-hour ambulatory blood pressure at the end of the 6-day long experiment and control periods. Additionally, we examined physiological stress (heart rate variability and urinary 8-hydroxy-2′-deoxyguanosine) while wearing the particulate respirators. Person- and exposure-level covariates were also considered in the model.@*RESULTS@#After the 6-day period of respirator use, resting blood pressure was reduced by 5.3 mmHg for systolic blood pressure (P = 0.013), 2.9 mmHg for mean arterial blood pressure (P = 0.079), and 3.6 mmHg for pulse pressure (P = 0.024). However, particulate respirator use was associated with changes in physiological stress markers. A parasympathetic activity marker (high frequency) significantly decreased by 24.0% (P = 0.029), whereas a sympathetic activity marker (ratio of low-to-high frequency) increased by 50.3% (P = 0.045). An oxidative stress marker, 8-hydroxy-2′-deoxyguanosine, increased by 3.4 ng/mg creatinine (P = 0.021) during the experimental period compared with that during the control period. Lung function indices indicated that wearing particulate respirators was protective; however, statistical significance was not confirmed.@*CONCLUSION@#Individual particulate respirator use may prevent PM(2.5)-induced blood-pressure elevation among elderly Korean women. However, the effects of particulate respirator use, including physiological stress marker elevation, should also be considered.TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0003526

Mild Anemia and Risk for All-Cause, Cardiovascular and Cancer Deaths in Apparently Healthy Elderly Koreans / 가정의학회지

BACKGROUND: Being common, mild anemia is sometimes considered a mere consequence of aging; however, aging alone is unlikely to lead to anemia. Therefore, this study aimed to investigate the association between mild anemia and total mortality and cause-specific mortality in apparently healthy elderly subjects. METHODS: A retrospective cohort study was conducted on 10,114 apparently healthy elderly individuals who underwent cancer screening and routine medical check-ups at one Health Promotion Center between May 1995 and December 2007. We defined mild anemia as a hemoglobin concentration between 10.0 g/dL and 11.9 g/dL in women and between 10.0 g/dL and 12.9 g/dL in men. We assessed the relationship between the overall, cardiovascular (CV), and cancer mortality and mild anemia using Cox proportional hazard models. RESULTS: Mild anemia was present in 143 men (3.1%) and 246 women (6.1%). During an average follow-up of 7.6 years, 495 deaths occurred, including 121 CV and 225 cancer deaths. After adjustments, mild anemia was associated with a 128% increase in the risk of all-cause mortality (hazard ratio [HR], 2.28; 95% confidence interval [CI], 1.54–3.37) in men and cancer-related mortality (HR, 2.25; 95% CI, 1.22–4.13), particularly lung cancer (HR, 2.70; 95% CI, 1.03–7.08) in men, but not in women. In the subgroup analyses based on smoking status, obesity, and age, the associations were more prominent in never or former smoker groups and the older group. CONCLUSION: The present study shows that overall and cancer-related mortality was associated with mild anemia in elderly men. Future prospective studies are needed to consolidate our findings.

High Temperatures and Kidney Disease Morbidity: A Systematic Review and Meta-analysis / 예방의학회지

OBJECTIVES@#In recent years, serious concerns have been raised regarding the impacts of rising temperatures on health. The present study was conducted to investigate the relationship between elevated temperatures and kidney disease through a systematic review and meta-analysis.@*METHODS@#In October 2017, 2 researchers independently searched related studies in PubMed and Embase. A meta-analysis was conducted using a random-effects model, including only studies that presented odds ratios, relative risks, or percentage changes, along with 95% confidence intervals (CIs). The characteristics of each study were summarized, and the Egger test and funnel plots were used to evaluate publication bias.@*RESULTS@#Eleven studies that met the criteria were included in the final analysis. The pooled results suggest an increase of 30% (95% CI, 20 to 40) in kidney disease morbidity with high temperatures. In a disease-specific subgroup analysis, statistically significant results were observed for both renal colic or kidney stones and other renal diseases. In a study design–specific subgroup analysis, statistically significant results were observed in both time-series analyses and studies with other designs. In a temperature measure–specific subgroup analysis, significant results were likewise found for both studies using mean temperature measurements and studies measuring heat waves or heat stress.@*CONCLUSIONS@#Our results indicate that morbidity due to kidney disease increases at high temperatures. We also found significant results in subgroup analyses. However, further time-series analyses are needed to obtain more generalizable evidence.

High Temperatures and Kidney Disease Morbidity: A Systematic Review and Meta-analysis / 예방의학회지

OBJECTIVES: In recent years, serious concerns have been raised regarding the impacts of rising temperatures on health. The present study was conducted to investigate the relationship between elevated temperatures and kidney disease through a systematic review and meta-analysis. METHODS: In October 2017, 2 researchers independently searched related studies in PubMed and Embase. A meta-analysis was conducted using a random-effects model, including only studies that presented odds ratios, relative risks, or percentage changes, along with 95% confidence intervals (CIs). The characteristics of each study were summarized, and the Egger test and funnel plots were used to evaluate publication bias. RESULTS: Eleven studies that met the criteria were included in the final analysis. The pooled results suggest an increase of 30% (95% CI, 20 to 40) in kidney disease morbidity with high temperatures. In a disease-specific subgroup analysis, statistically significant results were observed for both renal colic or kidney stones and other renal diseases. In a study design–specific subgroup analysis, statistically significant results were observed in both time-series analyses and studies with other designs. In a temperature measure–specific subgroup analysis, significant results were likewise found for both studies using mean temperature measurements and studies measuring heat waves or heat stress. CONCLUSIONS: Our results indicate that morbidity due to kidney disease increases at high temperatures. We also found significant results in subgroup analyses. However, further time-series analyses are needed to obtain more generalizable evidence.

Spatial and Temporal Trends of Number of Deaths Attributable to Ambient PM(2.5) in the Korea

BACKGROUND: We aimed to evaluate the spatial and temporal trends of the health burden attributable to particulate matter less than 2.5 µm in diameter (PM2.5) in the metropolitan cities and provinces of the Korea. METHODS: We used modeled PM2.5 concentration data for the basic administrative levels, comprising the cities and the provinces of Korea, the corresponding annual population census data for each level, and the age and cause specific mortality data. We applied cause-specific integrated exposure-response functions to calculate the premature mortality attributable to ambient PM2.5 for four disease end points (ischemic heart disease [IHD], chronic obstructive pulmonary disease [COPD], lung cancer [LC], and cerebrovascular disease [stroke]) for the year 2015. Moreover, the temporal trends of the health burden from 2006 to 2015 were assessed. RESULTS: The annual average PM2.5 concentration for Korea was 24.4 μg/m3, and 11,924 premature deaths were attributable to PM2.5 exposure in 2015. By simulating the reduction in the annual mean values of PM2.5 to 10 µg/m3, about 8,539 premature deaths were preventable. There was spatial variation in mortality burden attributable to PM2.5 across the sub-national regions of Korea. In particular, the high burden was concentrated at Seoul and Gyeonggi province due to the high population density. However, decreasing trends were noted for most of the metropolitan cities and provinces of Korea since 2006. CONCLUSION: Our findings show that further actions to improve air quality in Korea would substantially improve the health burden due to particulate matter.

The Association between Types of Smoking and Periodontal Disease according to the Survey Year Using the Fourth and Fifth Korea National Health and Nutrition Examination Surveys / 치위생과학회지

There is little evidence on the effects of environmental tobacco smoke (ETS) on prevalence of periodontal disease. The aims of this study were to explore the trends of prevalence of periodontal disease and types of exposure to smoke, including ETS according to the survey year, identify factors affecting periodontal disease, and compare the effect size of periodontal disease between active smokers and secondhand smokers. Data on 11,643 individuals were obtained from the fourth and fifth Korean National Health and Nutritional Examination Surveys. Information on exposure to ETS at home and work was self-reported. Severity of periodontal disease was evaluated using the community periodontal index. A multivariate logistic regression analysis was performed to model periodontal disease using types of smoking and the survey year. Overall, the prevalence of periodontal disease was 26.0% (n=3,029) and about 9% of the study population were secondhand smokers. The prevalence of periodontal disease among smokers was significantly increased according to smoking types by year. Active smokers showed a statistically significant adjusted odds ratio (aOR) for having periodontal disease except in the year 2007, whereas secondhand smokers had significant associations only in 2010 (aOR, 1.68; 95% confidence interval, 1.05 to 2.70) compared to non-smokers. For secondhand smokers, the statistical relationship of predicting periodontal disease was weaker than that of active smokers. However, ETS should separately be considered as an important risk factor for periodontal disease. This study suggested the need for further investigation of the impact of ETS on prevalence of periodontal disease using in-depth research designs and objective measurements for assessing periodontal disease and ETS.

The Association Between Oxidative Stress and Depressive Symptom Scores in Elderly Population: A Repeated Panel Study / 예방의학회지

OBJECTIVES: Previous epidemiological studies about oxidative stress and depression are limited by hospital-based case-control design, single-time measurements of oxidative stress biomarkers, and the small number of study participants. Therefore, in this study, we analyzed the association between biomarker of oxidative stress and depressive symptom scores using repeatedly measured panel data from a community-dwelling elderly population. METHODS: From 2008 to 2010, a total of 478 elderly participants residing in Seoul, Korea, were evaluated three times. Participants underwent the Korean version of the Short Form Generic Depression Scale (SGDS-K) test for screening depression, and urinary malondialdehyde (MDA) levels were measured as an oxidative stress biomarker. We used a generalized estimating equation with a compound symmetry covariance structure to estimate the effects of oxidative stress on depressive symptom scores. RESULTS: A two-fold increase in urinary MDA concentration was significantly associated with a 33.88% (95% confidence interval [CI], 21.59% to 47.42%) increase in total SGDS-K scores. In subgroup analyses by gender, a two-fold increase in urinary MDA concentration was significantly associated with increased SGDS-K scores in both men and women (men: 30.88%; 95% CI, 10.24% to 55.37%; women: 34.77%; 95% CI, 20.09% to 51.25%). In bivariate analysis after an SGDS-K score ≥8 was defined as depression, the third and the fourth urinary MDA quartiles showed a significantly increased odds ratio(OR) of depression compared to the lowest urinary MDA quartile (third quartile OR, 6.51; 95% CI, 1.77 to 24.00; fourth quartile OR, 7.11; 95% CI, 1.99 to 25.42). CONCLUSIONS: Our study suggests a significant association between oxidative stress and depressive symptoms in the elderly population.

Association between urinary 3-phenoxybenzoic acid and body mass index in Korean adults: 1st Korean National Environmental Health Survey

BACKGROUND: According to US-EPA report, the use of pyrethrins and pyrethroids has increased during the past decade, and their area of use included not only in agricultural settings, but in commerce, and individual household. It is known that urinary 3-PBA, major metabolite of pyrethroid, have some associations with health effect in nervous and endocrine system, however, there’s no known evidence that urinary 3-PBA have associations with obesity. METHOD: We used data of 3671 participants aged above 19 from the Korean National Environmental Health Survey in 2009–2011. In our analysis, multivariate piece-wise regression and logistic regression analysis were used to investigate the association between urinary 3-PBA (3-Phenoxybenzoic Acid) and BMI. RESULT: Log-transformed level of urinary 3-PBA had significantly positive association with BMI at the low-level range of exposure (p < 0.0001), and opposite associations were observed at the high level exposure (p = 0.04) after adjusting covariates. In piece-wise regression analysis, the flexion point that changes direction of the associations was at around 4 ug/g creatinine of urinary 3-PBA. As quintiles based on concentration of urinary 3-PBA increased to Q4, the ORs for prevalence of overweight (BMI ≥ 23 kg/m2) were increased, and the OR of Q5 was lower than that of Q4 (OR = 1.810 for Q4; OR = 1.483 for Q5). In the analysis using obesity (BMI ≥ 25 kg/m2) as outcome variable, significant associations were observed between obesity and quintiles of 3-PBA, however, there were no differences between the OR of Q5 and that of Q4 (OR = 1.659 for Q4; OR = 1.666 for Q5). CONCLUSION: Our analysis suggested that low-level of pyrethroid exposure has positive association with BMI, however, there is an inverse relationship above the urinary 3-PBA level at 4 ug/g creatinine. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s40557-015-0079-7) contains supplementary material, which is available to authorized users.

Interaction of Vitamin D and Smoking on Inflammatory Markers in the Urban Elderly / 예방의학회지

OBJECTIVES: Epidemiological studies have reported that vitamin D deficiency is associated with inflammatory disease. Smoking is a well-known risk factor for inflammation. However, few studies have investigated the interactive effect of vitamin D deficiency and smoking on inflammation. This study aims to investigate the interaction of vitamin D and smoking with inflammatory markers in the urban elderly. METHODS: We used data from the Korean Elderly Environmental Panel Study, which began in August 2008 and ended in August 2010, and included 560 Koreans > or =60 years old living in Seoul. Data was collected via questionnaires that included items about smoking status at the first visit. Vitamin D levels, high-sensitivity C-reactive protein (hs-CRP), and white blood cell (WBC) counts were repeatedly measured up to three times. RESULTS: The association of vitamin D and hs-CRP was significant after adjusting for known confounders (beta=-0.080, p=0.041). After separate analysis by smoking status, the association of vitamin D deficiency and hs-CRP in smokers was stronger than that in nonsmokers (smokers: beta=-0.375, p=0.013; non-smokers: beta=-0.060, p=0.150). Smoking status was an effect modifier that changed the association between vitamin D deficiency and hs-CRP (interaction estimate: beta=-0.254, p=0.032). Vitamin D was not significantly associated with WBC count (beta=0.003, p=0.805). CONCLUSIONS: Vitamin D deficiency was associated with hs-CRP in the urban elderly. Smoking status was an effect modifier of this association. Vitamin D deficiency was not significantly associated with WBC count.

Physical Activity- and Alcohol-dependent Association Between Air Pollution Exposure and Elevated Liver Enzyme Levels: An Elderly Panel Study / 예방의학회지

OBJECTIVES: The deleterious effects of air pollution on various health outcomes have been demonstrated. However, few studies have examined the effects of air pollution on liver enzyme levels. METHODS: Blood samples were drawn up to three times between 2008 and 2010 from 545 elderly individuals who regularly visited a community welfare center in Seoul, Korea. Data regarding ambient air pollutants (particulate matter < or =2.5 mum [PM2.5], nitrogen dioxide [NO2], ozone [O3], carbon monoxide, and sulfur dioxide) from monitoring stations were used to estimate air pollution exposure. The effects of the air pollutants on the concentrations of three liver enzymes (aspartate aminotransferase [AST], alanine aminotransferase [ALT], and gamma-glutamyltranspeptidase [gamma-GTP)]) were evaluated using generalized additive and linear mixed models. RESULTS: Interquartile range increases in the concentrations of the pollutants showed significant associations of PM2.5 with AST (3.0% increase, p=0.0052), ALT (3.2% increase, p=0.0313), and gamma-GTP (5.0% increase, p=0.0051) levels; NO2 with AST (3.5% increase, p=0.0060) and ALT (3.8% increase, p=0.0179) levels; and O3 with gamma-GTP (5.3% increase, p=0.0324) levels. Significant modification of these effects by exercise and alcohol consumption was found (p for interaction <0.05). The effects of air pollutants were greater in non-exercisers and heavy drinkers. CONCLUSIONS: Short-term exposure to air pollutants such as PM2.5, NO2, and O3 is associated with increased liver enzyme levels in the elderly. These adverse effects can be reduced by exercising regularly and abstinence from alcohol.

Spatial analysis of PM10 and cardiovascular mortality in the Seoul metropolitan area

OBJECTIVES: Numerous studies have revealed the adverse health effects of acute and chronic exposure to particulate matter less than 10 mum in aerodynamic diameter (PM10). The aim of the present study was to examine the spatial distribution of PM10 concentrations and cardiovascular mortality and to investigate the spatial correlation between PM10 and cardiovascular mortality using spatial scan statistic (SaTScan) and a regression model. METHODS: From 2008 to 2010, the spatial distribution of PM10 in the Seoul metropolitan area was examined via kriging. In addition, a group of cardiovascular mortality cases was analyzed using SaTScan-based cluster exploration. Geographically weighted regression (GWR) was applied to investigate the correlation between PM10 concentrations and cardiovascular mortality. RESULTS: An examination of the regional distribution of the cardiovascular mortality was higher in provincial districts (gu) belonging to Incheon and the northern part of Gyeonggido than in other regions. In a comparison of PM10 concentrations and mortality cluster (MC) regions, all those belonging to MC 1 and MC 2 were found to belong to particulate matter (PM) 1 and PM 2 with high concentrations of air pollutants. In addition, the GWR showed that PM10 has a statistically significant relation to cardiovascular mortality. CONCLUSIONS: To investigate the relation between air pollution and health impact, spatial analyses can be utilized based on kriging, cluster exploration, and GWR for a more systematic and quantitative analysis. It has been proven that cardiovascular mortality is spatially related to the concentration of PM10.