Limits...
Associations between ozone and morbidity using the Spatial Synoptic Classification system.

Hanna AF, Yeatts KB, Xiu A, Zhu Z, Smith RL, Davis NN, Talgo KD, Arora G, Robinson PJ, Meng Q, Pinto JP - Environ Health (2011)

Bottom Line: In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions.Ozone was associated with MI only under the extreme moist tropical (5-day lag) air masses.Elevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute for the Environment, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. ahanna@unc.edu

ABSTRACT

Background: Synoptic circulation patterns (large-scale tropospheric motion systems) affect air pollution and, potentially, air-pollution-morbidity associations. We evaluated the effect of synoptic circulation patterns (air masses) on the association between ozone and hospital admissions for asthma and myocardial infarction (MI) among adults in North Carolina.

Methods: Daily surface meteorology data (including precipitation, wind speed, and dew point) for five selected cities in North Carolina were obtained from the U.S. EPA Air Quality System (AQS), which were in turn based on data from the National Climatic Data Center of the National Oceanic and Atmospheric Administration. We used the Spatial Synoptic Classification system to classify each day of the 9-year period from 1996 through 2004 into one of seven different air mass types: dry polar, dry moderate, dry tropical, moist polar, moist moderate, moist tropical, or transitional. Daily 24-hour maximum 1-hour ambient concentrations of ozone were obtained from the AQS. Asthma and MI hospital admissions data for the 9-year period were obtained from the North Carolina Department of Health and Human Services. Generalized linear models were used to assess the association of the hospitalizations with ozone concentrations and specific air mass types, using pollutant lags of 0 to 5 days. We examined the effect across cities on days with the same air mass type. In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions.

Results: Ozone was associated with asthma under dry tropical (1- to 5-day lags), transitional (3- and 4-day lags), and extreme moist tropical (0-day lag) air masses. Ozone was associated with MI only under the extreme moist tropical (5-day lag) air masses.

Conclusions: Elevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass. Certain synoptic circulation patterns/air masses in conjunction with ambient ozone levels were associated with increased asthma and MI hospitalizations.

Show MeSH

Related in: MedlinePlus

Monthly average hospital admissions rate (per day) for asthma and myocardial infarction for the five cities.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3117763&req=5

Figure 2: Monthly average hospital admissions rate (per day) for asthma and myocardial infarction for the five cities.

Mentions: The seasonal distribution of daily hospital admission rates for the nine years of data considered for the study is shown in Figure 2. The asthma and MI daily hospital admission rates are the highest for Charlotte, followed by Raleigh, due to the relatively large populations of these cities. The hospitalization rate for MI is almost always higher than for asthma in all five cities. The asthma hospitalization rates depict a seasonal pattern, with highest admissions during the fall and winter, while the MI hospitalization rates are more nearly constant throughout the year. Also noticeable are the relatively high asthma and MI hospital admission rates for Asheville compared to Wilmington (the two smaller cities).


Associations between ozone and morbidity using the Spatial Synoptic Classification system.

Hanna AF, Yeatts KB, Xiu A, Zhu Z, Smith RL, Davis NN, Talgo KD, Arora G, Robinson PJ, Meng Q, Pinto JP - Environ Health (2011)

Monthly average hospital admissions rate (per day) for asthma and myocardial infarction for the five cities.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3117763&req=5

Figure 2: Monthly average hospital admissions rate (per day) for asthma and myocardial infarction for the five cities.
Mentions: The seasonal distribution of daily hospital admission rates for the nine years of data considered for the study is shown in Figure 2. The asthma and MI daily hospital admission rates are the highest for Charlotte, followed by Raleigh, due to the relatively large populations of these cities. The hospitalization rate for MI is almost always higher than for asthma in all five cities. The asthma hospitalization rates depict a seasonal pattern, with highest admissions during the fall and winter, while the MI hospitalization rates are more nearly constant throughout the year. Also noticeable are the relatively high asthma and MI hospital admission rates for Asheville compared to Wilmington (the two smaller cities).

Bottom Line: In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions.Ozone was associated with MI only under the extreme moist tropical (5-day lag) air masses.Elevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass.

View Article: PubMed Central - HTML - PubMed

Affiliation: Institute for the Environment, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA. ahanna@unc.edu

ABSTRACT

Background: Synoptic circulation patterns (large-scale tropospheric motion systems) affect air pollution and, potentially, air-pollution-morbidity associations. We evaluated the effect of synoptic circulation patterns (air masses) on the association between ozone and hospital admissions for asthma and myocardial infarction (MI) among adults in North Carolina.

Methods: Daily surface meteorology data (including precipitation, wind speed, and dew point) for five selected cities in North Carolina were obtained from the U.S. EPA Air Quality System (AQS), which were in turn based on data from the National Climatic Data Center of the National Oceanic and Atmospheric Administration. We used the Spatial Synoptic Classification system to classify each day of the 9-year period from 1996 through 2004 into one of seven different air mass types: dry polar, dry moderate, dry tropical, moist polar, moist moderate, moist tropical, or transitional. Daily 24-hour maximum 1-hour ambient concentrations of ozone were obtained from the AQS. Asthma and MI hospital admissions data for the 9-year period were obtained from the North Carolina Department of Health and Human Services. Generalized linear models were used to assess the association of the hospitalizations with ozone concentrations and specific air mass types, using pollutant lags of 0 to 5 days. We examined the effect across cities on days with the same air mass type. In all models we adjusted for dew point and day-of-the-week effects related to hospital admissions.

Results: Ozone was associated with asthma under dry tropical (1- to 5-day lags), transitional (3- and 4-day lags), and extreme moist tropical (0-day lag) air masses. Ozone was associated with MI only under the extreme moist tropical (5-day lag) air masses.

Conclusions: Elevated ozone levels are associated with dry tropical, dry moderate, and moist tropical air masses, with the highest ozone levels being associated with the dry tropical air mass. Certain synoptic circulation patterns/air masses in conjunction with ambient ozone levels were associated with increased asthma and MI hospitalizations.

Show MeSH
Related in: MedlinePlus