Air pollution and hospital admissions for asthma in a subtropical city: Taipei, Taiwan

This study was undertaken to determine whether there is an association between exposure to air pollutants levels and number of hospital admissions for asthma in Taipei, Taiwan. Hospital admissions for asthma and ambient air pollution data for Taipei were obtained for the period from 1996 through 2003. The relative risk of hospital admission for asthma was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-air-pollutant model, on warm days (> or = 25 degrees C) statistically significant positive associations were found for SO2, NO2, and CO levels with an increase in asthmatic admissions. On cool days (< 25 degrees C), all air pollutants were significantly associated with elevated asthma admissions except SO2. For the two-air-pollutant model, CO significantly increases hospital admissions for asthma in combination with each of the other four pollutants on warm days. On cool days, NO2 and O3 significantly elevated asthma rates in all the two-air-pollutant models. This study provides evidence that higher levels of ambient air pollutant concentrations increase the risk of hospital admissions for asthma.     

Air pollution and hospital admissions for pneumonia in a subtropical city: Taipei, Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and hospital admissions for pneumonia in Taipei, Taiwan. Hospital admissions for pneumonia and ambient air pollution data for Taipei were obtained for the period from 1996-2004. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single pollutant models, on warm days (>23 degrees C) statistically significant positive associations were found in all pollutants. On cool days (<23 degrees C), all pollutants were significantly associated with pneumonia admissions except SO(2). For the two-pollutant model, O(3) and NO(2) were significant in combination with each of the other 4 pollutants on warm days. On cool days, PM(10), CO, and O(3) remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient air pollutants increase the risk of hospital admissions for pneumonia.     

Air pollution and hospital admissions for congestive heart failure in a tropical city: Kaohsiung, Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and hospital admissions for congestive heart failure (CHF) in Kaohsiung, Taiwan. Hospital admissions for CHF and ambient air pollution data for Kaohsiung were obtained for the period 1996-2004. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant models, on warm days (> 25 degrees C) statistically significant positive associations were found in all pollutants except sulfur dioxide (SO(2)). On cool days (< 25 degrees C), all pollutants were significantly associated with CHF admissions. For the two-pollutant model, CO and O(3) were significant in combination with each of the other four pollutants on warm days. On cool days, NO(2) remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient air pollutants increase the risk of hospital admissions for CHF and that the effects of air pollutants on hospital admissions for CHF were temperature dependent.     

Air pollution and hospital admissions for chronic obstructive pulmonary disease in a subtropical city: Taipei, Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and hospital admissions for chronic obstructive pulmonary disease (COPD) in Taipei, Taiwan. Hospital admissions for COPD and ambient air pollution data for Taipei were obtained for the period 1996-2003. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant model, on warm days (> or = 20 degrees C) statistically significant positive associations were found in all pollutants except sulphur dioxide (SO2). However, statistically significant effects for COPD admissions on cool days (< 20 degrees C) were observed only for SO2 levels. For the two-pollutant model, NO2 and O3 were significant in combination with each of the other four pollutants on warm days. This study provides evidence that higher levels of ambient air pollutants increases the risk of hospital admissions for COPD in Taiwan.     

Association between fine particulate air pollution and hospital admissions for chest pain in a subtropical city: Taipei,Taiwan

This study determined the association between fine particles (PM_2.5) levels and hospital admissions for chest pain (CP) in Taipei, Taiwan. Hospital admissions for CP and ambient air pollution data for Taipei were obtained for the period 2009–2013. The relative risk of hospital admissions was estimated using a case-crossover approach, after controlling for weather variables, day of the week, seasonality, and long-term time trends. For single-pollutant models (without adjustment for other pollutants), increased frequency of CP admissions was significantly associated with PM_2.5 levels on warm days (>23°C), with an interquartile range rise correlated with a 15% (95% confidence interval = 11–31%) elevation in number of CP admissions. In two-pollutant models, PM_2.5 remained significant after inclusion of each of the other four pollutants: sulfur dioxide (SO₂), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃) on warm days. Generally, no marked associations were observed between PM_2.5 levels and risk of CP admissions on cool days in both single- and two-pollutant models. This study provides evidence that higher PM_2.5 concentrations enhance the risk of hospital admissions for CP on warm days.     

Fine particulate air pollution and hospital admissions for congestive heart failure: a case-crossover study in Taipei

Abstract

This study was undertaken to determine whether there was an association between fine particles (PM_2.5) levels and hospital admissions for congestive heart failure (CHF) in Taipei, Taiwan. Hospital admissions for CHF and ambient air pollution data for Taipei were obtained for the period 2006–2010. The relative risk of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality and long-term time trends. For the single pollutant model (without adjustment for other pollutants), increased CHF admissions were significantly associated with PM_2.5 both on warm days (>23?°C) and cool days (<23?°C), with an interquartile range increase associated with a 13% (95% CI?=?9–17%) and 3% (95% CI?=?0–7%) increase in CHF admissions, respectively. In the two-pollutant models, PM_2.5 remained significant after the inclusion of SO₂ or O₃ both on warm and cool days. This study provides evidence that higher levels of PM_2.5 increase the risk of hospital admissions for CHF.     

Air pollution and emergency room visits for cardiac arrhythmia in a subtropical city: Taipei,Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and emergency room (ER) visits for cardiac arrhythmia in Taipei, Taiwan. ER visits for cardiac arrhythmia and ambient air pollution data for Taipei were obtained for the period 2000–2006. The relative risk of ER visits was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant model, on warm days (≥23°C), statistically significant positive associations were found for all pollutants except SO₂. On cool days (<23°C), all pollutants were also significantly associated with the number of ER visits for cardiac arrhythmia, except SO₂. For the two-pollutant model, results for O₃ and NO₂ remained statistically significant on both warm and cool days. This study provides evidence that higher levels of ambient air pollutants increase the risk of ER visits for cardiac arrhythmia.     

Air pollution and hospital admissions for pneumonia in a tropical city: Kaohsiung, Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and hospital admissions for pneumonia in Kaohsiung, Taiwan. Hospital admissions for pneumonia and ambient air pollution data for Kaohsiung were obtained for the period of 1996-2004. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant models, on warm days (= 25 degrees C) statistically significant positive associations were found for all pollutants. On cool days (< 25 degrees C), all pollutants were also significantly associated with number of pneumonia admissions. For the two-pollutant model, O3 and CO were significant in combination with each of the other four pollutants on warm days. On cool days, PM10 and NO2 remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient air pollutants increase the risk of hospital admissions for pneumonia. The effects of air pollutants on hospital admissions for pneumonia were temperature dependent.     

Air pollution and hospital admissions for asthma in a tropical city: Kaohsiung, Taiwan

This study was undertaken to determine whether there is an association between air pollutants levels and hospital admissions for asthma in Kaohsiung, Taiwan. Hospital admissions for asthma and ambient air pollution data for Kaohsiung were obtained for the period from 1996 through 2003. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant models, on warm days (> or = 25 degrees C) statistically significant positive associations were found in all pollutants except sulfur dioxide (SO2). On cool days (< or = 25 degrees C) all pollutants were significantly associated with asthma admissions For the two pollutant models, CO and O3 were significant in combination with each of the other four pollutants on warm days. On cool days NO2 remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient pollutants increase the risk of hospital admissions for asthma.     

Correlation between air pollution and postneonatal mortality in a subtropical city: Taipei, Taiwan

With growing evidence of the association between daily mortality and air pollution exposure in adults, it is important to investigate whether infants are also susceptible. The purpose of this study was to examine the relationship between air pollution exposure and postneonatal, defined as infant of more than 27 d and less than 1 yr old, mortality in Taipei, Taiwan's largest city, which has a subtropical climate, for the period 1994-2000, using a case-crossover analysis. This design is an alternative to Poisson time-series regression for studying the short-term adverse health effects of air pollution. The air pollutants examined included particulate matter (PM10), sulfur dioxide (SO2), ozone (O3), nitrogen dioxide (NO2), and carbon monoxide (CO). The risk of postneonatal deaths was estimated to increase by 3.1% for PM10, 4.1% for SO2, 1.7% for NO2, 3.8% for CO, and 0.1% for O3 for each interquartile range change, respectively. However, the associations were without statistical significance. The established link between air pollution levels and infant mortality may not be as strong in cities with subtropical climates, although other factors such as differences in pollutant component composition or the underlying health of the postneonates may explain the lack of a strong association in this study. Further studies of this type in cities with varying climates and cultures are needed.     

Air pollution and hospital admissions for chronic obstructive pulmonary disease in a tropical city: Kaohsiung, Taiwan

This study was undertaken to determine whether there is an association between air pollutants levels and hospital admissions for chronic obstructive pulmonary disease (COPD) in Kaohsiung, Taiwan. Hospital admissions for COPD and ambient air pollution data for Kaohsiung were obtained for the period from 1996 to 2003. The odds ratio of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant models, on warm days (> or =25 degrees C) statistically significant positive associations were found in all pollutants except sulphur dioxide (SO2). On cool days (< 25 degrees C), all pollutants were significantly associated with COPD admissions. For the two-pollutant models, CO and O3 were significant in combination with each of the other four pollutants on warm days. On cool days, NO2 remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient pollutants increase the risk of hospital admissions for COPD.     

Association between gaseous air pollution and hospital admissions for hypertension in Taipei,Taiwan

Air pollution exposure has been reported to influence blood pressure. However, only a few epidemiological studies demonstrated association between ambient air pollution exposure and acute hypertensive events. The aim of this study was to examine the association between gaseous air pollutants exposure and hospital admissions for hypertension in Taipei, Taiwan. Data on hospital admissions for hypertension and ambient air pollution in Taipei were obtained for the 2009–2013 period. An odds ratio (OR) for number of hospital admissions for hypertension associated with each interquartile range increase in each gaseous air pollutant was calculated using a case-crossover approach, after controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single-pollutant model, significant correlation was observed between number of hospital admissions for hypertension and ozone (O₃) levels both on warm (>23°C) and cool (<23°C) days, with OR of 1.2 (95% confidence interval [CI] = 1.03–1.4) and 1.2 (95% CI = 1.02–1.42), respectively. No significant associations were found between levels of other gaseous pollutants and risk of hospital admissions for hypertension. In the two-pollutant model, O₃ levels remained significant after inclusion of particulate matter 10 μm or less in diameter (PM₁₀), sulfur dioxide (SO₂), or carbon monoxide (CO) on warm days. On cool days, O₃ levels remained significant after inclusion of air pollutants other than SO₂. These findings indicated that O₃ exposure may trigger a rise in blood pressure to a level that results in higher number of hospital admissions.     

Effects of ambient air pollution exposure on frequency of hospital admissions for appendicitis in Taipei,Taiwan

The relationship between exposure to ambient air pollutants and hospital admissions for appendicitis is not known. This study examined whether an association existed between air contaminant levels and frequency of hospital admissions for appendicitis in Taipei, Taiwan. Ambient air pollution and hospital admission data for Taipei were obtained for 2009–2013. Relative risk (RR) of hospital admissions was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single pollutant model, on warm days (> 23°C), number of appendicitis admissions was significantly associated with particulate matter (PM_2.5), nitrogen dioxide (NO₂), carbon monoxide (CO), and ozone (O₃). On cool days (< 23°C), a significant rise in number of admissions for appendicitis was related to PM₁₀, NO₂, and O₃ concentrations. In the two-pollutant models, on warm days, NO₂ and O₃ were significantly associated with increased number of admissions for appendicitis when combined with each of the other pollutants. On cool days, NO₂, O₃, and PM₁₀ remained significant for higher appendicitis admission cases in all two-pollutant models. In conclusion, higher levels of ambient air pollutants may be associated with increase in the risk of hospital admissions for appendicitis in Taipei.     

Air pollution and postneonatal mortality in a tropical city: Kaohsiung, Taiwan

With growing evidence of the association between daily mortality and air pollution in adults, it is important to investigate whether infants are also susceptible to the adverse health effects of ambient air pollutants. The purpose of this study is to examine the relationship between air pollution and postneonatal mortality in Kaohsiung, Taiwan, a large industrial city with a tropical climate, during the period 1994-2000, using a case-crossover analysis. Case-crossover analysis provides an alternative to Poisson time-series regression for studying the short-term adverse health effects of air pollution. The air pollutants examined included particulate matter (PM(10)), sulfur dioxide (SO(2)), ozone (O(3)), nitrogen dioxide (NO(2)), and carbon monoxide (CO). The risk of postneonatal deaths was estimated to increase by 4.0% per 67 microg/m(3) (the interquartile range in daily ambient concentration of PM(10)) for PM(10), 1.8% per 17.84 ppb for NO(2), 5.1% per 0.31 ppm for CO, and 4.6% per 19.20 ppb for O(3). Although positive, none of these associations achieved statistical significance. The established link between air pollution levels and infant mortality may not be as strong in cities with tropical climates, although other factors such as differences in pollutant mix or the underlying health of the postneonates may explain the lack of a strong association in this study. Further studies of this type in cities with varying climates and cultures are needed.     

Fine particulate air pollution associated with increased risk of hospital admissions for hypertension in a tropical city,Kaohsiung, Taiwan

The aim of this study was to assess whether a correlation exists between fine particles (PM_2.5) levels and number of hospital admissions for hypertension in Kaohsiung, Taiwan. Hospital admission frequency and ambient air pollution data were obtained for Kaohsiung for 2009–2013. A time-stratified case-crossover method was used to estimate relative risk for hospital admissions, controlling for weather, day of the week, seasonality, and long-term time trends. Odds ratios and 95% confidence intervals were calculated for a 10 µg/m³ increment of PM_2.5 for lags from days 0 to 6. Data showed no significant associations between PM_2.5 levels and number of hypertension-related hospital admissions on warm days (>25°C). However, on cool days (<25°C), a significant positive association was found with frequency of hypertension admissions in the single-pollutant model (without adjusting for other pollutants) with a 10 µg/m³ rise in PM_2.5 on day of admission (lag 0) associated with a 12% increase in number of admissions for hypertension. In the two-pollutant model, the association of PM_2.5 with rate of hypertension hospitalizations remained significant after including SO₂ or O₃ on lag day 0. Data demonstrate that an association between short-term exposure to PM_2.5 and elevated risk of hypertension-related hospital admissions may exist in Kaohsiung, Taiwan, a tropical city.     

Effects of Asian dust storm events on daily hospital admissions for cardiovascular disease in Taipei, Taiwan

In spring, windblown dust storms originating in the deserts of Mongolia and China make their way to Taipei city. These occurrences are known as Asian dust storm (ADS) events. The objective of this study was to assess the possible effects of ADS on the hospital cardiovascular disease (CVD) admissions of residents in Taipei, Taiwan, during the period from 1996 to 2001. Fifty-four dust storm episodes, which were classified as index days, were identified. Daily CVD admissions on index days were compared with admissions on comparison days. Two comparison days were selected for each index day, 7 d before the index day and 7 d after the index day. The effects of dust storms on CVD were prominent 1 d after the event (3.65% increase). However, the association was not statistically significant. Nonetheless, it may be worthwhile to focus more on the potential adverse effects of ADS events in the future.     

Air particulate pollution and hospital admissions for chronic obstructive pulmonary disease in Reno, Nevada

This study assessed the association between ambient PM(10) pollution and daily hospital admissions for chronic obstructive pulmonary disease (COPD) in Reno-Sparks, Nevada, for the period 1990-1994. All three hospitals in the region were included. There was a total of 3115 admissions for COPD during this period. Daily ambient PM(10) values were available from one of seven air monitoring stations in this region. Weather variables including temperature and wind speed were also collected from this station. The daily average concentration of PM(10) was 36.55 microg/m(3). The generalized additive model (GAM) was used in the whole analysis. After adjusting for the effects of weather variables, day of week, seasons, and time trend, the results show that PM(10) is a statistically significant predictor for daily hospital admissions for COPD. The relative risk (RR) of hospital admissions for COPD for an interquartile increase (26.6 microg/m(3)) of the 24-h average level of PM(10) is 1.049 (95% CI 1.011-1.087).     

Effects of Asian dust storm events on hospital admissions for chronic obstructive pulmonary disease in Taipei, Taiwan

In spring, windblown dust storms originating in the deserts of Mongolia and China make their way to Taipei city. These occurrences are known as Asian dust storm (ADS) events. These ADS events lead to enhanced PM(10) levels over that contributed by the usual local sources. The objective of this study was to assess the possible associations of PM(10) with hospital admissions for chronic obstructive pulmonary disease (COPD) in Taipei, Taiwan, during the period 1996-2001. We identified 54 dust storm episodes that were classified as index days. Daily COPD admissions on the index days were compared with admissions on the comparison days. We selected 2 comparison days for each index day, 7 days before the index days and 7 days after the index days. The effects of dust storms on hospital admissions for COPD were prominent 3 days after the event (relative risk = 1.057; 95% confidence interval = 0.982-1.138). However, the association was not statistically significant. There may not have been enough power to detect associations resulting from the inadequate sample size of COPD admissions on ADS events days. However, It seems worthwhile to pay more attention to the ADS events and health in the future.     

Air Pollution and Hospital Admissions for Pneumonia in a Subtropical City: Taipei,Taiwan

This study was undertaken to determine whether there was an association between air pollutant levels and hospital admissions for pneumonia in Taipei, Taiwan. Hospital admissions for pneumonia and ambient air pollution data for Taipei were obtained for the period from 1996–2004. The relative risk of hospital admission was estimated using a case-crossover approach, controlling for weather variables, day of the week, seasonality, and long-term time trends. In the single pollutant models, on warm days (>23°C) statistically significant positive associations were found in all pollutants. On cool days (<23°C), all pollutants were significantly associated with pneumonia admissions except SO₂. For the two-pollutant model, O₃ and NO₂ were significant in combination with each of the other 4 pollutants on warm days. On cool days, PM_{1 0}, CO, and O₃ remained statistically significant in all the two-pollutant models. This study provides evidence that higher levels of ambient air pollutants increase the risk of hospital admissions for pneumonia.     

Consequences of exposure to Asian dust storm events on daily pneumonia hospital admissions in Taipei, Taiwan

In spring, windblown dust storms originating in the deserts of Mongolia and China travel to Taipei city. These occurrences are known as Asian dust storm (ADS) events. The objective of this study was to assess the possible associations of constituents of ADS with hospital pneumonia admissions of residents in Taipei, Taiwan, during the period 1996-2001. Fifty-four dust storm episodes were identified and were classified as index days. Daily pneumonia admissions on the index days were compared with admissions on comparison days. Two comparison days for each index day, 7 d before the index days and 7 d after the index days, were selected. The study results indicated a statistically significant association between ADS events and daily pneumonia admissions 1 d after the event. It is worthwhile to pay more attention to ADS events and health in the future based on the findings in this investigation.