194696 Adult asthma prevalence by urban-rural residence—United States, 2007

Sunday, November 8, 2009

Teresa Ann Morrison, MD MPH , National Center of Environmental Health (NCEH), Centers for Disease Control and Prevention (CDC), Atlanta, GA
David Callahan, MD , National Center of Environmental Health (NCEH), Centers for Disease Control and Prevention (CDC), Atlanta, GA
Jeanne E. Moorman, MS , National Center of Environmental Health (NCEH), Centers for Disease Control and Prevention, Atlanta, GA
Cathy Bailey, MS , National Center of Environmental Health (NCEH), Centers for Disease Control and Prevention (CDC), Atlanta, GA
Rationale: Approximately 20 million persons in the United States have asthma. Although geographically narrow studies suggest that asthma prevalence is higher in urban versus rural areas, a multi-state urban-rural comparison has not been published. We analyzed national survey data to estimate asthma prevalence among U.S. adults by urban-rural residence and to determine the relative contributions of sociodemographic and health behavior characteristics on the probability of reporting asthma.

Methods: We linked the 2007 Behavioral Risk Factor Surveillance System (BRFSS) to Urban Influence Codes (UICs) to categorize respondents with asthma on an urban-rural scale. BRFSS is an annual state-based telephone survey that collects health data. In 2007, all 50 states asked about asthma. UICs classify counties on an urban-rural scale based on population size and adjacency to metropolitan areas. We used UICs to categorize respondents into four urban-rural groups (metropolitan, adjacent metropolitan, micropolitan, and remote). We calculated weighted estimates for asthma prevalence and generated odds ratios (ORs) for the association between asthma and urban-rural residence after adjusting for selected characteristics.

Results: Overall asthma prevalence (8.3%; 95% CI=8.07-8.43) was not statistically different (p=0.32) across urban-rural groups. After adjusting for selected characteristics, all non-metropolitan groups (adjacent metropolitan: OR=0.94; 95% CI=0.87-1.00; micropolitan: OR=0.93; 95% CI=0.84-1.03; and remote: OR=0.97; 95% CI=0.88-1.08) were as likely to report current asthma as the metropolitan group.

Conclusions: Asthma prevalence is as high in rural areas as urban areas. Because these results substantially change our understanding of asthma prevalence in rural areas, further investigation is needed to understand geographic-related risk factors.

Learning Objectives:
1. Explain the public health importance of comparing asthma prevalence by residence. 2. Describe how to link national survey data to other data sources to determine disease prevalence by residence. 3. Compare current asthma prevalence on an urban-rural scale

Keywords: Asthma, Rural Populations

Presenting author's disclosure statement:

Qualified on the content I am responsible for because: I am a medical epidemiologist and pediatrician commissioned in the United States Public Health Service who serves on the Asthma Epidemiology Research Team at the Air Pollution and Respiratory Health Branch of the National Center for Environmental Health (NCEH). I have presented at national and international conferences on current and past investigations related to asthma occurrence and management.
Any relevant financial relationships? No

I agree to comply with the American Public Health Association Conflict of Interest and Commercial Support Guidelines, and to disclose to the participants any off-label or experimental uses of a commercial product or service discussed in my presentation.

See more of: Chronic Disease Epidemiology Poster Session
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