Wright State University CORE Scholar
Master of Public Health Program Student Publications Master of Public Health Program
2016
Is the Breeze Making you Wheeze? Air Quality and Asthma in the US
Gaurav A. Nagar Wright State University - Main Campus
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Repository Citation Nagar, G. A. (2016). Is the Breeze Making you Wheeze? Air Quality and Asthma in the US. Wright State University, Dayton, Ohio.
This Master's Culminating Experience is brought to you for free and open access by the Master of Public Health Program at CORE Scholar. It has been accepted for inclusion in Master of Public Health Program Student Publications by an authorized administrator of CORE Scholar. For more information, please contact library- [email protected]. Running head: AIR QUALITY AND ASTHMA IN THE US 1
Is the breeze making you wheeze? Air Quality and Asthma in the US
Gaurav A Nagar
Wright State University
28th March, 2016
AIR QUALITY AND ASTHMA IN THE US 2
Acknowledgements
I would like to express my deepest gratitude to my parents for their sacrifices. Thanks to
Prof. Naila Khalil M.B.B.S., M.P.H., Ph.D. for her assistance and guidance during this project.
Thanks to Prof. Ramzi Nahhas, Ph.D. for his advice as a co-chair. Thanks to Dr. Nikki Rogers,
Ph.D. for her support throughout the duration of the Culminating Experience. My heart felt gratitude to the faculty and staff at Center for Global Health, Wright State University, for their support and encouragement during my journey through the MPH program. And last but not least, a special thanks to my wife and daughter for their support and encouragement.
AIR QUALITY AND ASTHMA IN THE US 3
Table of Contents
Abstract ...... 4
Introduction ...... 5
Statement of Purpose ...... 6
Research Questions ...... 6
Review of Literature ...... 6
Methods...... 14
Results ...... 15
Discussion ...... 19
Conclusion ...... 20
References ...... 21
Appendices ...... 25
Appendix A - Table 2 Values from Individual States ...... 25
Appendix B - List of Public Health Competencies Met in CE ...... 28
AIR QUALITY AND ASTHMA IN THE US 4
Abstract
Objective: A secular trend towards increased current and lifetime asthma prevalence has been
observed in the US. The current study compared ambient Air Quality Index (AQI) data and
asthma prevalence data from all fifty US states.
Methods: Air pollution is measured as AQI by the US Environmental Protection Agency (EPA).
County level AQI data are available at the EPA website. Asthma prevalence data for each state
are available on the Centers for Disease Control and Prevention (CDC) website. Data from 50
US states (2011-2013) were analyzed for AQI and asthma prevalence. The average of proportions for all counties in each state was used to obtain a mean value for good air quality days (“Good Days”) in each year. An Analysis of Variance (ANOVA) was conducted to evaluate if 1) asthma prevalence and 2) AQI differences across 2011, 2012 and 2013. A regression analysis was conducted to assess the association between AQI and asthma prevalence.
Results: The analysis showed a reduction in air pollution from 2011 to 2013. The ANOVA
revealed that this decrease in AQI was significant, F (2, 147) = 5.7678, p = 0.0039. While an
increase in asthma prevalence was observed from 2011 to 2013,the ANOVA revealed that the
increased asthma prevalence was not significant, F (2, 147) = 0.2794, p = 0.7566. Regression
analysis showed no significant association between AQI and asthma prevalence (p>0.05).
Conclusion: US Asthma prevalence did not change significantly despite significant AQI
reduction from 2011 to 2013; AQI was not related to asthma prevalence.
Keywords: AQI, Allergy, Allergic Asthma, Bronchial Asthma, Pollution AIR QUALITY AND ASTHMA IN THE US 5
Is the breeze making you wheeze? Air Quality and Asthma in the US
Public health professionals have been intrigued by the increasing incidence of reported asthma cases in the United States (US). Behavioral Risk Factor Surveillance System (BRFSS) is a state-based system of health surveys in the US. BRFSS is one of the major sources for data on asthma prevalence in the US. According to BRFSS lifetime prevalence of asthma in the US has steadily increased from 7% to 8% between years 2000 and 2010. The Centers for Disease
Control and Prevention (CDC) notes that 1 in 12 people (about 26 million) had asthma in 2010, compared with 1 in 14 (about 20 million) in 2001 (Centers for Disease Control and Prevention
[CDC], 2015). Current asthma prevalence has increased from 8.6% to 9.6% during the same period (CDC, 2015). In a report published by Global Asthma Network (GAN) in 2014, in general, asthma became more common throughout the world, especially in children, from 1993 to 2003. However, there is inadequate data to accurately access the local and regional trends in asthma prevalence globally. This is especially true in middle and low income countries. There is a need to close the data gap in these countries in order to encourage evidence based decision making in public health. Therefore, the GAN has undertaken assessment of asthma as a key responsibility of the organization (Global Asthma Network [GAN], 2014).
There could be many possible reasons for the increase in asthma prevalence including air pollution, race, income, gender and location. While factors such as race, income and gender can explain higher rates of asthma in certain communities, they do not explain the secular trend towards increased incidence of asthma. Air pollution is a known risk factor for asthma. Is there a correlation between increased asthma incidence and outdoor air pollution?
AIR QUALITY AND ASTHMA IN THE US 6
Statement of Purpose
The purpose of this research project was to explore the relationship between outdoor air pollution and asthma prevalence.
Research Questions
• Hypothesis 1) The prevalence of asthma is increasing over time in 50 states of the US.
• Hypothesis 2) The Air Quality Index (AQI) is increasing over time in 50 states of the US.
• Hypothesis 3) There is a correlation between AQI and asthma.
Review of Literature
Signs and Symptoms of Asthma
Asthma is a chronic inflammatory disease of the airways. The inflammation causes the airways to become unusually sensitive and hyper-reactive to various irritants (allergens). The airways constrict and produce excessive mucus and swelling. This causes difficulty in breathing.
The patient may cough and show signs of shortness of breath. There is a characteristic “wheeze” on expiration, due to narrowing of the airways.
Etiology of Asthma
Asthma is thought to be caused by a combination of environmental, genetic and epigenetic factors (Dietert, 2011). (See Figure 1) AIR QUALITY AND ASTHMA IN THE US 7
Allergen Virus
Air Exercise Pollution
Foods/ Cold Air Additives
Emotional Drugs stress Asthma
Figure 1. Various factors affecting Asthma prevalence.
Outdoor air pollution is considered a major environmental factor in the exacerbation of asthma. Daily air quality is measured and reported as Air Quality Index (AQI) by the
Environmental Protection Agency (EPA) (2015). AQI is a number from 0 to 500. A higher AQI number means more polluted air (Table 1).
Table 1
Air Quality Index chart guide (EPA.gov)
Air Quality Index (AQI) Level of health concern Color coding Values When AQI is in this …air quality …as symbolized range… conditions are: by this color: 0-50 Good Green
51-100 Moderate Yellow
101-150 Unhealthy for sensitive groups Orange
151-200 Unhealthy Red
201-250 Very Unhealthy Purple
251-300 Hazardous Maroon AIR QUALITY AND ASTHMA IN THE US 8
EPA also calculates the AQI for five major air pollutants, separately. These pollutants are
regulated by the Clean Air Act (CAA) (2015). The CAA is a Federal Law that regulates air
emissions from stationary and mobile sources. A salient feature of the Law is that it authorizes
EPA to establish National Ambient Air Quality Standards to protect health and welfare of the
public and to regulate emissions of hazardous air pollutants (Clean Air Act [CAA], 2015). The
five major air pollutants are: particulate matter, ground level ozone, carbon monoxide, sulfur
dioxide, and nitrogen dioxide (Environmental Protection Agency [EPA], 2015). High particulate matter and ozone levels are most detrimental to respiratory health.
Effect of Particulate Matter on Respiratory Health
Particulate Matter (PM) comes from various sources including power plants, vehicle tailpipes, industrial processes and forest fires. PM is further subdivided into PM2.5 and PM10
depending upon the size in micron meters. PM2.5 particles are smaller than 2.5 microns while
PM10 particles are between 2.5 and 10 microns in size. High levels of PM are considered to be
responsible for excessive sputum production, lung disease, asthma attacks and even heart attacks
and strokes (CDC, 2013). In fact, PM2.5 has been identified as a leading risk factor for premature
mortality worldwide (Giorgini et al., 2015). One study investigated the effects of various
constituents of PM on asthma and other respiratory ailments in school children up to 12 years of
age. It showed that PM rich in Iron, Copper and Zinc was associated with higher incidence of
asthma and allergies in children (Gehring et al., 2015). These elements are abundant in places
with poorly regulated non-tailpipe emissions from road traffic. PM concentrations can reach very
high values in cities, especially densely populated areas in developing economies. This is largely
due to burning of unclean fuels like coal and diesel. PM can be captured using special types of
filters called HEPA filters. AIR QUALITY AND ASTHMA IN THE US 9
Effect of PM on Biological Pathways
Systematic evidence demonstrates credible pathways by which acute and chronic exposures to air pollutants might cause autonomic imbalance and vasoconstriction. Autonomic imbalance includes augmented release of various pro-oxidative and inflammatory mediators.
Together, these responses may be the cause of PM induced BP elevations (Giorgini et al., 2015).
High PM concentrations in air can cause oxidative stress and mitochondrial dysfunction at the cellular level (Wang, Garcia, & Zhang, 2012). Lately, there is increasing evidence that PM can cause notable dysregulation of gene expression through both genetic and non-genetic factors.
Recent studies suggest that PM can alter epigenetic markers through methylation of DNA and modification of histones. This is one mechanism thought to contribute to the pathogenesis of cardiovascular disease. It may also contribute to increasing prevalence of asthma and even lung cancer (Wang et al., 2012). Modulated activities of Histone Acetylase, Histone Deacetylase and
DNA Methyltransferase may also contribute to the epigenetic changes induced by PM and related chemicals (Wang et al., 2012).
Effect of Ozone on Respiratory Health
Ozone is an oxidized state of Oxygen. Ozone molecule is unstable and is a powerful oxidizing agent itself. It is formed at ground level by action of sunlight on Nitrogen Oxides and
Volatile Organic Compounds. These reactants come from diverse sources like vehicle exhausts, power plants, industrial solvents and paints. Typical weather for Ozone formation is a hot summer day with plenty of sunshine (CDC, 2013). Ozone can cause coughing, wheezing and lung damage. It can increase mortality due to respiratory causes and possibly heart disease. One study specifically looked at cohorts of the American Cancer Society Cancer Prevention Study II which were matched with corresponding air pollution data from 96 metropolitan statistical areas AIR QUALITY AND ASTHMA IN THE US 10
in the US. It was concluded that higher concentrations of either PM2.5 or ozone were significantly
associated with an increased risk of death from cardiopulmonary causes. In fact, PM2.5 was linked
to the risk of death from cardiovascular causes, whereas ozone was associated with the risk of
death from respiratory causes (Jerrett et al., 2009). One study in Newark, NJ showed that high
levels of ozone were associated, in a statistically significant manner, with increased pediatric
Emergency Department visits due to asthma. The results were similar across both time series and case crossover study designs (Gleason & Fagliano, 2015).
Effect of Nitrogen Oxides on Asthma Rates
Nitrogen Dioxide is a major component of a family of highly reactive gases called
Nitrogen Oxides (NOx) that are produced as a result of fossil fuel combustion (EPA, 2015). A
time series, ecological study conducted in Brazil, concluded that exposure to Nitrogen Oxides
(NOx) discharged by combustion of fossil fuels, is associated with increased incidence of asthma
and other respiratory disease. Even at NOx levels below the acceptable standards, there is an
increase in morbidity (Cesar, Carvalho, Jr., & Nascimento, 2015).
Effect of SO2 on Asthma Rates
Sulfur dioxide is a byproduct of fossil fuel combustion. It is also a gaseous respiratory
irritant and is a public health concern in industrialized and urban locations (EPA, 2015).
Increased levels of SO2 from petroleum refineries in Montreal, Canada has been shown to
increase asthma prevalence among children attending school in the vicinity (Deger et.al, 2012).
Effect of Air Pollution on Asthma Rates
Air pollution due to traffic congestion has a direct impact on asthma rates. This has been
demonstrated in various studies worldwide. One such study was conducted in Atlanta, during the
1996 Olympics. The government implemented changes in transportation strategy to reduce the AIR QUALITY AND ASTHMA IN THE US 11 levels of air pollution throughout the city. The study captured data on children aged 1 to 16 years who resided in metropolitan Atlanta. The data showed that reduction in ambient air pollution levels resulted in reduction in admissions, due to acute asthma attacks, in hospitals (Friedman,
Powell, Hutwagner, Graham, & Teague, 2001). Another study conducted in seven Metropolitan
Statistical Areas (MSA) of Eastern USA concluded that PM2.5 had larger effect on mortality than ambient ozone did (Hou, Strickland, Liao, 2015). One study conducted in Shanghai, China sought to find correlation between black carbon (soot), PM2.5 and childhood asthma. It concluded that the effect of black carbon on childhood asthma was slightly higher than PM2.5 (Hua et al.,
2014). Another study sought to identify the increased risk of asthma in people living in close proximity to major roadways. The study was conducted on children and teenagers in Poland. As expected, there was a positive correlation between proximity to a major roadway and asthma symptoms. Reported asthmatic symptoms were highest in respondents within 200 meters of a major roadway. The incidence gradually declined from 200 to 500 meters. Respondents living more than 500 meters from a major roadway had the lowest rates of asthma (Porebski, Wozniak,
& Czarnobilska, 2014). Yet another study in Sweden found that at moderate levels of exposure
3 i.e. NOx levels 12.1ugm/m (95% CI 9.80 to 10.5) to traffic pollution does not appear to affect the quality of life with respect to respiratory health (Sommar et al., 2014). Results were somewhat different in a case-crossover study conducted in Windsor, Canada. A statistically significant positive correlation was observed between Air Quality Health Index levels and visits to the Emergency Department (ED) due to asthma attacks. The Odds Ratio of ED visits was 1.17
(CI=1.09 to 1.26) for adults and 1.11(CI=1.01 to 1.21) for children and adolescents
(Szyszkowicz & Kousha, 2014). Researchers have documented that long term improvements in air quality are associated with statistically significant improvement in lung function and AIR QUALITY AND ASTHMA IN THE US 12
development in children (Gauderman, 2015). In Southern California, there has been a downward
trend in air pollution levels. This has resulted in a reduction in prevalence of asthma in cities like
Los Angeles according to University of Southern California (USC, 2015).
Effect of Air Pollution on Lung Function
Apart from the conclusive epidemiological evidence, there have been several laboratory
studies which confirm that air pollution adversely affects lung function, especially in asthmatics.
It impairs mucociliary clearance by damaging airway mucus membrane. This promotes the access of inhaled allergens to the cells of the immune system. Increased contact of allergens facilitates sensitization of the immune system. Consequently, a more severe Immunoglobulin E
(IgE) response to the allergens occurs. This causes inflammation of the airways. This could account for increasing prevalence of asthma in polluted urban areas (D’Amato, Cecchi,
D'Amato, & Liccardi, 2010).
Vitamin D levels in Asthmatics
Vitamin D levels have been observed to be lower in asthmatic patients when compared to healthy individuals (Tamasauskiene, Gasiuniene, Lavinskiene, Sakalauskas, & Sitkauskiene,
2015). Atmospheric air pollution prevents UV radiation from reaching the earth’s surface. UV
radiation helps in synthesis of vitamin D. There is a positive correlation between increased
asthma prevalence and low vitamin D levels. However, a possible cause and effect has not been
demonstrated conclusively.
Effect of Global Warming on Asthma Incidence
According to the EPA, climate change can increase the incidence of asthma by increasing
surface temperatures and causing dry conditions. This could lead to increased incidence of
wildfires, causing air pollution. Increased temperatures also cause a rise in allergens like pollen, AIR QUALITY AND ASTHMA IN THE US 13 particulate matter, and ozone and methane gas. Climatologists and other scientists have concluded that the earth’s temperature is increasing, mainly due to anthropogenic factors like greenhouse gas emissions (mostly Carbon dioxide and Methane). Climate change alters the concentration and dispersal of air pollutants. Warmer weather is prolonged which also increases the seasonal presence of allergenic pollen in the atmosphere. These factors have a substantial influence on the increasing prevalence of asthma throughout the world (D’Amato et al., 2010).
Air Pollution and Cardiovascular Disease
Elevated concentrations of air pollutants increase hospital admissions and emergency room visits for hypertension and cardiovascular disorders (Szyszkowicz & Kousha, 2014).
Studies also show that blood pressure (BP) increases with increasing PM levels in vulnerable subsets of population like elderly and pregnant women (Giorgini et al., 2015). Therefore, PM mediated increase in BP may be an important pathway in the causation of cardiovascular events.
Environmental Health Justice
Lastly, it is apt to mention the concept of respiratory health equality promulgated by the
American Thoracic Society. The document acknowledges that respiratory health differs across various demographic groups within the US. Attainment of respiratory health equality requires ending respiratory health disparities. This objective can be achieved by collaboration of multiple disciplines to eliminate detrimental environmental exposures which disproportionately affect certain demographics (Celedon, Roman, Schraufnagel, Thomas, & Samet, 2014).
AIR QUALITY AND ASTHMA IN THE US 14
Methods
The study was a secondary data analysis of two variables: 1) The AQI data were obtained
from US EPA (EPA, 2015) and; 2) the asthma data were acquired from US CDC (2015).
Analysis of Variance (ANOVA) was used to test Hypothesis 1 (The prevalence of asthma is
increasing over time in the 50 states). The values of mean of proportion of “Good Days”
amongst the reported days, were analyzed using ANOVA to test Hypothesis 2 (AQI is increasing
over time in the 50 states). Linear regression analyses was performed to test Hypothesis 3 (There
is a correlation between AQI and asthma) for each year from 2011 to 2013.
For each county (where data were available) within each state the proportion of days with low levels of air pollution (low AQI), were categorized as “Good Days” amongst all days of the year. The mean of proportions of “Good Days” for these counties was then used to obtain an average value for good air quality days, “Good Days”, in each state in each year. Asthma data were only available at state level and not for each county. Thus, county level AQI data were transformed to state level data so it could be compared to asthma prevalence in each state.
Data from all states were assessed for asthma prevalence for three consecutive years from
2011 to 2013. ANOVA was used to assess if trend of asthma prevalence changed significantly over the three years of observation. Likewise, ANOVA of the mean of proportion of “Good
Days” among all reported days, was utilized to test if AQI trend changed significantly over the three years of observation time. To assess statistical association between AQI (continuous variable) and asthma prevalence (continuous variable), a simple linear regression was performed for each year separately. The significance level for hypothesis tests was α = 0.05 (two-tailed).
Descriptive statistics included mean of proportions and graphical displays were presented as bar
graphs and scatter-plots. ANOVA and regression analysis was performed using Statistical AIR QUALITY AND ASTHMA IN THE US 15
Package for the Social Science (SPSS) (IBM SPSS Statistics for Windows, Version 23.0.
Armonk, NY: IBM Corp., 2015).
Results
Table 2
Mean Asthma Prevalence (no. of cases per 1,000 population) and Mean of proportion of “Good
Days” from 2011-20131
Asthma Asthma Asthma Good Days Good Days Good Days 2011 2012 2013 2011 2012 2013 Mean 9.018 9.054 9.188 0.7884 0.7921 0.8326
1Please refer to Appendix A for the values from individual states.
Figure 2 illustrates that asthma prevalence increased in the US from 2011 to 2013.
Asthma prevalence increased by 0.4% from 2011 to 2012 and by 1.5% from 2012 to 2013.
9.25
9.2 9.188
9.15
9.1 9.054 9.05 9.018 Mean Prevalence 9
8.95
8.9 2011 2012 2013 Year
Figure 2. Mean of asthma prevalence in the US states from 2011 to 2013 AIR QUALITY AND ASTHMA IN THE US 16
It is evident from Figure 3 that proportion of “Good” air quality days had increased in the
US from 2011 to 2013. This indicated that outdoor air pollution had generally decreased from
2011 to 2013. Air pollution decreased by 0.47% from 2011 to 2012 and by 5.11% from 2012 to
2013.
0.84 0.8326 0.83
0.82
0.81
0.8 0.7921 0.7884 0.79
0.78 Proportion of "Good Days"
0.77
0.76 2011 2012 2013 Year
Figure 3. Mean of the proportion of “Good Days” in US states from 2011 to 2013
In 2011 the “Good Days” explained less than 1% of the variance in asthma prevalence.
Since p>0.05, this result was statistically insignificant (see Figure 4). AIR QUALITY AND ASTHMA IN THE US 17
Figure 4. Scatterplot for prevalence of asthma vs. “Good Days” in 2011.
In 2012 the “Good Days” explained less than 1% of the variance in asthma prevalence. Since p>0.05, this result was statistically insignificant (see Figure 5).
Figure 5. Scatterplot for prevalence of asthma vs. “Good Days” in 2012.
In 2013 the “Good Days” explained less than 1% of the variance in asthma prevalence.
Since p>0.05, this result was statistically insignificant (see Figure 6). AIR QUALITY AND ASTHMA IN THE US 18
Figure 6. Scatterplot for prevalence of asthma vs. “Good Days” in 2013.
Hypothesis 1) the prevalence of asthma is increasing over time in 50 states of the US.
The ANOVA revealed that the prevalence of asthma did not change significantly over time from
2011 to 2013, F (2, 147) = 0.2794, p = 0.7566. Therefore, hypothesis 1 is not supported.
Hypothesis 2) AQI is increasing over time in 50 states of the US. Assessment of mean of proportion of “Good Days” showed that air quality had actually improved from 2011 to 2013.
The ANOVA revealed that the decrease in AQI was significant, F (2, 147) = 5.7678, p = 0.0039.
Therefore, hypothesis 2 is not supported.
Hypothesis 3) there is a correlation between AQI and Asthma. Regression analysis was used to test if the “Good Days” significantly predicted the prevalence of asthma in 2011, 2012 and 2013 (Figures 4, 5, and 6). The results of the regression indicated, for each year from 2011 to
2013, the “Good Days” explained less than 1% of the variance in asthma prevalence (2011: R=
0.028, F (1, 49) =0.036, p = 0.849); (2012: R= 0.004, F (1, 49) =0.001, p = 0.979); (2013:
R=0.028, F (1, 49) =0.037, p = 0.848). It was found that “Good Days” did not significantly AIR QUALITY AND ASTHMA IN THE US 19
predict the prevalence of Asthma in 2011, 2012 or 2013 (p >0.05). Therefore, hypothesis 3 is not
supported.
Discussion
Asthma prevalence increased from 2011 to 2013. However, this trend was not statistically significant. Outdoor air pollution decreased from 2011 to 2013 as reflected by an increase in the number of “Good Days” annually. This reduction was statistically significant. However, the regression analysis demonstrated that there was only a weak, non-significant correlation between
prevalence of asthma and AQI in all three years. The AQI values did not correlate with
prevalence of asthma in the respective communities. This suggests that while outdoor air
pollution is a known cause of asthma, there may be confounding factors which may influence the
prevalence of asthma in a community. These factors may include socio-economic status, smoking habits and genetic susceptibility, housing conditions and indoor air quality (Celedon et al., 2014). As the literature suggests, race is an important factor. African Americans in Ohio are twice as likely to have asthma when compared to Caucasians (CDC, 2015). Income plays a significant role too. Those making less than $15,000/year are more than two times as likely to have asthma when compared to those making more than $50,000/year. Certain age groups including children and elderly have higher incidence of asthma. Asthma rates are significantly higher in adult women when compared to adult men. Impoverished geographical areas, such as rural Appalachian region, have significantly higher incidence of asthma (CDC, 2015). Indoor air pollution and second hand smoke also contribute to the incidence of asthma (CDC, 2015). Stieb,
Szyszkowicz, Brian, FAU & Leech (2009) conducted a time-series analysis on ED visits to
Canadian hospitals. They concluded that high daily average concentrations of O3 in ambient air
were consistently associated with increased ED visits due to respiratory conditions. The study AIR QUALITY AND ASTHMA IN THE US 20
also concluded that high levels of PM10 and PM2.5 were strongly linked to visits for asthma
during warm season.
Strengths of the study included the fact that this was an exhaustive analysis of data from two national data sources, namely the CDC and EPA. As data from all 50 states were included, it represented around 314 million US residents from approximately 3,000 counties. Although a number of studies have utilized air pollution, referencing to individual pollutants, AQI is a relatively novel concept to express the aggregated levels of air pollutants. The use of AQI as a chronic disease morbidity index, has been supported in previous studies (To et al, 2013).
Association of AQI with asthma has not been fully assessed (To et al., 2013). In an effort to fill
the gap, this concept has been applied in this study.
However this study should be evaluated in context of its limitations. We did not have
access to confounding variables such as race, income, age and gender.
Conclusion
Increasing prevalence of asthma in the US may have multiple causes. Air pollution is one
of the many contributing factors for increased asthma prevalence. Any attempt, by public health
practitioners, to reduce the morbidity due to asthma in a community should include addressing
racial, income, gender and regional disparities. Further research is needed to ascertain the
relative significance of all the risk factors in contributing to the morbidity due to asthma.
AIR QUALITY AND ASTHMA IN THE US 21
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AIR QUALITY AND ASTHMA IN THE US 25
Appendix A – Table 2 Values from Individual States
Table 2
Mean Asthma Prevalence (no. of cases per 1,000 population) and Mean of proportion of “Good
Days” from 2011-2013
Asthma Asthma Asthma Good Days Good Days Good Days State 2011 2012 2013 2011 2012 2013 AL 8.0 8.6 8.5 0.7506 0.8265 0.8849
AK 8.2 9.0 9.3 0.8908 0.8854 0.8966
AZ 9.6 8.6 8.9 0.6606 0.6474 0.6851
AR 9.5 8.8 8.3 0.7151 0.7779 0.8223
CA 8.4 8.8 8.7 0.6086 0.6328 0.6048
CO 8.3 8.9 9.1 0.8092 0.7929 0.8259
CT 9.9 9.9 9.8 0.8393 0.7556 0.7335
DE 9.8 9.9 10.6 0.7361 0.7116 0.7679
FL 7.6 8.2 8.3 0.8377 0.8899 0.9027
GA 9.6 8.2 8.4 0.6239 0.7242 0.7946
HI 9.5 8.9 9.4 0.6559 0.7010 0.7149
ID 9.2 8.5 8.5 0.8959 0.8383 0.8603
IL 8.1 8.5 7.6 0.8134 0.7836 0.8700
IN 9.6 9.1 10.3 0.7111 0.7177 0.7955
IA 8.3 8.1 7.8 0.7107 0.7003 0.7452
KS 8.8 8.4 8.9 0.8352 0.8210 0.8931
KY 10.4 11.1 9.5 0.7812 0.7804 0.8826
LA 6.4 7.4 7.7 0.7122 0.7532 0.8164 AIR QUALITY AND ASTHMA IN THE US 26
Asthma Asthma Asthma Good Days Good Days Good Days State 2011 2012 2013 2011 2012 2013 ME 12.0 11.1 11.9 0.9202 0.9352 0.9258
MD 8.5 9.0 9.4 0.6985 0.7079 0.8164
MA 10.7 10.8 11.4 0.7747 0.8097 0.8272
MI 9.9 10.5 11.5 0.8295 0.7650 0.8557
MN 7.0 8.0 7.7 0.8495 0.8683 0.8702
MS 7.7 8.1 8.2 0.7078 0.7497 0.8699
MO 9.2 10.4 10.8 0.7241 0.6748 0.7902
MT 9.1 9.5 8.6 0.8507 0.8132 0.8746
NE 7.3 7.4 7.3 0.8572 0.8214 0.876
NV 8.1 7.4 7.6 0.8801 0.8048 0.8122
NH 11.0 10.2 11.0 0.8108 0.8796 0.8797
NJ 9.0 8.7 9.0 0.7455 0.7655 0.8209
NM 10.0 9.2 9.2 0.8296 0.8615 0.8669
NY 9.7 9.3 9.7 0.8427 0.8523 0.8800
NC 8.8 7.7 8.4 0.7536 0.8446 0.8853
ND 8.1 7.6 8.3 0.9301 0.8996 0.9092
OH 9.8 10.5 9.7 0.7214 0.6963 0.7896
OK 9.6 10.2 9.0 0.6958 0.7286 0.8118
OR 10.4 10.6 11.4 0.8266 0.8487 0.7836
PA 9.0 10.1 9.6 0.6801 0.6762 0.7378
RI 11.3 10.8 12.0 0.8211 0.8486 0.8378
SC 8.2 8.7 8.4 0.7726 0.8469 0.8805 AIR QUALITY AND ASTHMA IN THE US 27
Asthma Asthma Asthma Good Days Good Days Good Days State 2011 2012 2013 2011 2012 2013 SD 6.9 7.5 7.9 0.8990 0.8083 0.8452
TN 7.2 7.7 7.1 0.7896 0.7821 0.8485
TX 7.4 6.8 7.3 0.7320 0.7784 0.8122
UT 8.8 8.9 9.0 0.8047 0.7537 0.7566
VT 11.1 10.9 11.3 0.8173 0.8827 0.8788
VA 8.7 8.7 8.7 0.8635 0.8921 0.9321
WA 9.7 9.7 9.9 0.8712 0.8590 0.8293
WV 9.2 10.2 9.0 0.7866 0.7794 0.8619
WI 9.2 8.6 10.4 0.8480 0.8016 0.8583
WY 9.1 9.0 9.1 0.8985 0.8271 0.9105
Mean 9.018 9.054 9.188 0.7884 0.7921 0.8326
AIR QUALITY AND ASTHMA IN THE US 28
Appendix B - Public Health Competencies Met in CE
Tier 1 Core Public Health Competencies Domain #1: Analytic/Assessment Skills Describes factors affecting the health of a community (e.g., equity, income, education, environment) Identifies quantitative and qualitative data and information (e.g., vital statistics, electronic health records, transportation patterns, unemployment rates, community input, health equity impact assessments) that can be used for assessing the health of a community Applies ethical principles in accessing, collecting, analyzing, using, maintaining, and disseminating data and information Uses information technology in accessing, collecting, analyzing, using, maintaining, and disseminating data and information Selects valid and reliable data Identifies gaps in data Collects valid and reliable quantitative and qualitative data Uses quantitative and qualitative data Contributes to assessments of community health status and factors influencing health in a community (e.g., quality, availability, accessibility, and use of health services; access to affordable housing) Explains how community health assessments use information about health status, factors influencing health, and assets and resources Domain #2: Policy Development/Program Planning Skills Identifies current trends (e.g., health, fiscal, social, political, environmental) affecting the health of a community Describes how public health informatics is used in developing, implementing, evaluating, and improving policies, programs, and services (e.g., integrated data systems, electronic reporting, knowledge management systems, geographic information systems) Domain #3: Communication Skills n/a Domain #4: Cultural Competency Skills n/a Domain #5: Community Dimensions of Practice Skills n/a Domain #6:Public Health Sciences Skills Describes the scientific foundation of the field of public health Describes how public health sciences (e.g., biostatistics, epidemiology, environmental health sciences, health services administration, social and behavioral sciences, and public health informatics) are used in the delivery of the 10 Essential Public Health Services Retrieves evidence (e.g., research findings, case reports, community surveys) from print and electronic sources (e.g., PubMed, Journal of Public Health Management and Practice, Morbidity and Mortality Weekly Report, The World Health Report) to support decision making Recognizes limitations of evidence (e.g., validity, reliability, sample size, bias, generalizability) Describes evidence used in developing, implementing, evaluating, and improving policies, programs, and services Domain #7: Financial Planning and Management Skills n/a Domain #8: Leadership and Systems Thinking Skills Contributes to development of a vision for a healthy community (e.g., emphasis on prevention, health equity for all, excellence and innovation)
AIR QUALITY AND ASTHMA IN THE US 29
Concentration Specific Competencies Public Health Management A knowledge of ethical principles relative to data collection, usage, and reporting results Detailed knowledge of public health laws and regulations