Asthma Health Disparities in Pittsburgh and Philadelphia

This study uses spatial analysis to explore social and policy level factors related to asthma burden in regions of Pennsylvania


National Burden of Asthma

As of 2019,  25 million Americans  have asthma, and 20 million adults (<18) have asthma. Asthma causes a major burden on the healthcare system where the estimated cost of asthma in the U.S in 2013 was approximately  82 billion dollars . Given that asthma can be controlled with effective management strategies and medications, this lung disease is viewed as preventable and an unnecessary cost to the healthcare system. Despite the preventable nature of asthma, there are racial and ethnic disparities in asthma burden in the U.S such that  African Americans are 40% more likely to have asthma  relative to white Americans. Therefore, it is necessary to take a holistic approach to understand the burden of asthma given that this inflammatory condition impacts some communities more than others.


Asthma in Pennsylvania: Allegheny County

Asthma is increasing in Pennsylvania. From 2011 to 2019, asthma prevalence has increased by  three percent. 

Figure 1. Allegheny County 2018 Asthma Prevalence for Adults

Allegheny County, PA

 In Allegheny County , twice as many Black individuals have asthma relative to their white counterparts. Figure 1 shows the prevalence of asthma in Allegheny County. Areas in the City of Pittsburgh and adjacent to the city have high prevalence of asthma.

Figure 2. Asthma Prevalence among Adults in Philadelphia, PA in 2018

Philadelphia, PA

In 2021, Philadelphia was  ranked  the seventh most challenging places to live with asthma. The burden of asthma is particularly high among racial and ethnic minoritized groups.  Black individuals in Philadelphia are almost three times more likely to die from asthma  that white individuals. Figure 2 indicates in which districts asthma prevalence is the highest. The lower north and west areas of Philadelphia have the worst burden of asthma.


Problem

It is known that asthma can be triggered by environmental factors and therefore it is the view of some health practitioners that asthma can be resolved by simply taking  medications and following an asthma management plan.  Therefore, a patient that frequently visits the hospital or ED for asthma attacks may appear to have low compliance with recommended guidelines.

Asthma is a multifactorial disease that does not rely only on patient behavior and adherence to treatment plan. Asthmatic patients may have less access to asthma specialists, less access to primary care physicians, work in locations without smoking bans, and may not be able to  continuously afford asthma medications  despite having insurance. At a larger and more significant level, racially minoritized groups are at increased risk of facing social inequities which also impact their lived experience with asthma. Black individuals are more likely to live in communities with higher pollution, have less ability to move to locations with cleaner air, have less access to green spaces, have more targeted tobacco vendors and campaigns, and have lived in a society which frequently does not prioritize and resolve their health concerns. Therefore, there is a great need to not only understand the social factors that impact asthmatic patients, but to also provide policy solutions which may benefit the most historically underserved communities.


Methods and Objectives

This research uses ArcGIS to map factors associated with asthma disparities in Allegheny County and Philadelphia, PA. This work has several implications:

  1. To assess factors related to racial disparities in asthma outcomes in order to provide tailored policy solutions
  2. To demonstrate that factors of social inequities are not generally specific to the location, rather are common inequities shared across the U.S that have not been resolved

Results: General Factors Associated with Asthma

Smoking and Asthma: Allegheny County

Figure 3 shows the smoking prevalence in Allegheny County in purple squares and the asthma prevalence as the blue layer. The smoking prevalence in Allegheny County is higher in the City of Pittsburgh and adjacent communities. The smoking prevalence is higher where asthma prevalence is higher.

Smoking and Asthma: Philadelphia

Figure 4 is the associated with smoking prevalence and asthma in Philadelphia. Smoking prevalence is higher in the lower north and west relative to the northeast, south, and mid-west regions of Philadelphia. The smoking patterns are most high in regions where asthma prevalence is high.


Lack of Health Insurance and Asthma Prevalence: Allegheny County

Figure 5 plots circles to represent lack of health insurance in relation to asthma prevalence. A larger circle indicates a higher prevalence of lack of health insurance. The uninsured population is higher in the City of Pittsburgh and adjacent communities.

Lack of Health Insurance and Asthma Prevalence: Philadelphia

Figure 6 indicates that the insurance population is highest in the lower north, upper north, and southwest regions of Philadelphia.


Indoor Pollution and Asthma Prevalence

Environmental factors like smoking and demographic characteristics like insurance and socioeconomic status are known factors that impact asthma outcomes. Research is moving towards further understanding the role of indoor pollution. Those who live in older and/or poorer quality housing may be more exposed to mold and lead, which can exacerbate asthma symptoms. In addition, housing units in poor neighborhoods may have increased rodent and insect infestations which can also trigger asthma. The following maps use vacant housing and affordable housing to proxy this concept of indoor air pollution. In addition, the maps below are regions taken from Allegheny County and Philadelphia to explicitly show how asthma prevalence differs among close populations and also how exposure levels may differ between these adjacent communities.

Indoor Pollution: Allegheny County High Asthma Regions

Figure 7 plots the percent vacant housing, represented by the house symbol, the count of affordable housing units, shown by the black squares, and asthma prevalence represented in blue. The regions selected are municipalities in Allegheny County with varying levels of asthma prevalence. The areas with the highest prevalence of asthma are Wilkinsburg, Penn Hills, Swissvale, and Braddock Hills. These locations also have a higher percent vacant housing and a higher count of affordable housing units.

Areas with low asthma prevalence, such as Edgewood, Forest Hills, Churchill, and Wilkins also have a lower percent vacant housing and a lower count of affordable housing units. There is a clear association between housing conditions and asthma prevalence.

Table 1 assesses the relationship between housing pollution and asthma prevalence in Allegheny County. The municipalities with the highest asthma prevalence also have the highest counts of affordable housing units and vacant housing.

Indoor Pollution: Philadelphia High Asthma Regions

Figure 8 plots the points of affordable housing units and percent vacant housing. District 5, which has higher asthma prevalence, has higher vacant housing and a higher count of affordable housing units.


Conclusions

  • Areas with high asthma prevalence generally also had high lack of health insurance and high smoking prevalence
  • The areas with the worst asthma prevalence also had areas with more affordable housing units and vacant housing units
  • The differences in asthma by region were shared in Allegheny County and Philadelphia indicating that disparities have a common impact across the U.S and that those who live in poorer housing quality may always be the most at-risk

Future Directions

    Recommendations
  1. Explore how affordable housing and vacant housing may directly impact asthma outcomes
  2. Assess the utility of programs aimed at addressing smoking cessation and obtaining insurance as interventions for asthma
  3. Advocate for polices to ensure that those who live in areas with the most asthma prevalence have tailored asthma management plans and interventions to address pollution

References

1. Centers for Disease Control and Prevention. (2020). 2019 National Health Interview Survey data. U.S. Department of Health & Human Services. Retrieved from:  https://www.cdc.gov/asthma/nhis/2019/data.htm 

2.Agency for Healthcare Research and Quality. (2019). Healthcare Cost and Utilization Project (2018). U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Retrieved from:  https://www.cdc.gov/asthma/national-surveillance-data/healthcare-use.htm 

3.National Center for Health Statistics. (2019). National Hospital Ambulatory Medical Care Survey (2010-2018). U.S. Department of Health and Human Services, Centers for Disease Control and Prevention. Retrieved from:  https://www.cdc.gov/asthma/national-surveillance-data/healthcare-use.htm 

4. The Economic Burden of Asthma in the United States, 2008-2013.Nurmagambetov T, Kuwahara R, Garbe PAnn Am Thorac Soc. 2018 Mar; 15(3):348-356.

5. Yaghoubi M, Adibi A, Safari A, FitzGerald JM, Sadatsafavi M. The Projected Economic and Health Burden of Uncontrolled Asthma in the United States. Am J Respir Crit Care Med. 2019;200(9):1102-1112. doi:10.1164/rccm.201901-0016OC

6. https://minorityhealth.hhs.gov/omh/browse.aspx?lvl=4&lvlid=15

7.. https://www.health.pa.gov/topics/Documents/Programs/Asthma%20Prevalence%20Fact%20Sheet_6-1-2021.pdf

8. https://triblive.com/local/pittsburgh-allegheny/allegheny-county-board-of-health-approves-300k-for-asthma-study-90k-for-trees/

9. https://www.aafa.org/media/3040/aafa-2021-asthma-capitals-report.pdf

10. https://nextcity.org/features/view/why-racial-disparities-in-asthma-are-an-urban-planning-issue


Data Sources

Philly Districts:https://www.opendataphilly.org/dataset/city-council-districts/resource/35f1ddfe-301e-4cc0-a037-2efab2603390

Philadelphia County Census Tracts