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Asthma Prevalence, Health Care Use and Mortality, 2000-2001Asthma is a chronic respiratory disease characterized by episodes or attacks of inflammation and narrowing of small airways in response to asthma “triggers.” Asthma attacks can vary from mild to life-threatening and involve shortness of breath, cough, wheezing, chest pain or tightness, or a combination of these symptoms. Many factors can trigger an asthma attack, including allergens, infections, exercise, abrupt changes in the weather, or exposure to airway irritants, such as tobacco smoke. The burden from asthma in the United States has increased over the past 2 decades. Trends from 1980 to 1999 are presented in the CDC Asthma Surveillance Survey. This fact sheet presents the most recent national data on asthma gathered by the Centers for Disease Control and Prevention. Age-adjusted rates by race/ethnicity and gender are presented in the charts and may be used to compare asthma prevalence, morbidity and mortality between race/ethnicity and gender groups. Crude rates by race/ethnicity and gender are presented in Table 1 to show the actual burden of asthma among subgroups of the population. To compare groups, it is strongly recommended that age-adjusted estimates be used. Table 1. Crude rates for current asthma and asthma attack prevalence, 2001, and health care utilization, and mortality, 2000
* Data for health care use outcomes is not available for Hispanic ethnicity. Data for White and Black race for these outcomes include persons of Hispanic ethnicity. Prevalence, 2001:
Lifetime asthma diagnosis, current asthma, and asthma attack prevalence
Beginning with the 2001 National Health Interview Survey (NHIS), it is possible to make estimates of the population that reported having asthma at the time of the interview. This is referred to as current asthma prevalence and includes people who have been diagnosed with asthma by a health professional and who still have asthma. In 2001, 73 people per 1,000 or 20.3 million people, had asthma at the time of the interview (Figure 2). Rates decreased with age; 87 per 1,000 children 0-17 years (6.3 million children) had asthma compared to 69 per 1,000 adults 18 years and over (14 million adults). When race/ethnicity is considered, current asthma prevalence was about 10% higher among non-Hispanic blacks compared to non-Hispanic whites and about 40% higher compared to Hispanics. Females had a 30% higher prevalence compared to males. However, this pattern was reversed among children. The current asthma prevalence rate for boys aged 0-17 years (99 per 1,000) was over 30% higher than the rate among girls (74 per 1,000).
Asthma attack prevalence, or the number of people who had at least one asthma attack in the previous year, is also available from the NHIS. The asthma attack prevalence is a crude indicator of how many people have uncontrolled asthma and are at risk for a poor outcome from asthma such as hospitalization. In 2001, 43 people per 1,000 (12 million people) had experienced an asthma attack in the previous year (Figure 3). That is, about 60% of the people who had asthma at the time of the survey had an asthma attack in the previous year. Asthma attack prevalence also decreased with age; 57 per 1,000 children 0-17 years (4.2 million children) had an asthma attack in the previous year compared to 38 per 1,000 adults aged 18 years and over (7.8 million adults). Non-Hispanic blacks had an asthma attack prevalence about 20% higher than non-Hispanic whites and almost 60% higher than Hispanics. Females had an asthma attack prevalence almost 40% higher than males.
Health Care Use, 2000
There were 1.8 million visits to EDs for asthma in 2000, or 67 per 10,000 people (Figure 5). Children aged 0-17 years had over 728,000 ED visits, a rate of 104 per 10,000. The ED visit rate was highest among children aged 0-4 years at 180 per 10,000. Adults 18 years and over had 54 ED visits per 10,000. The ED visit rate for blacks was 125% higher than that for whites, and for females, about 30% higher than for males.
There were 465,000 asthma hospitalizations in 2000, or 17 per 10,000 people (Figure 6). Among children 0-17 years, there were 214,000 hospitalizations (30 per 10,000). Hospitalizations were highest among children 0-4 years who had 67 hospitalizations per 10,000. The asthma hospitalization rate for blacks was 220% higher than for whites. Females had a hospitalization rate 25% higher than males.
Mortality
Data SourcesPrevalence: National Health Interview Survey, NCHS, CDC Outpatient visits, emergency room visits: National Ambulatory Medical Care Survey and National Hospital Ambulatory Medical Care Survey, NCHS, CDC Hospitalizations: National Hospital Discharge Survey, NCHS, CDC Mortality: Mortality component of the National Vital Statistics System, NCHS, CDC U.S. Population to calculate health care utilization and mortality rates: noninstitutionalized civilian population (ambulatory care rates), civilian population (hospitalization rates), and residential population (mortality rates): U.S. Bureau of the Census (revised December 26, 2001) Sources of informationData on asthma: Surveillance for Asthma --- United States, 1980--1999, Centers for Disease Control and Prevention National Heart, Lung, and Blood Institute Morbidity and Mortality Chartbook Economic and social costs: Weiss KB, Sullivan SD. The health economics of asthma and rhinitis. I. Assessing the economic impact. J Allergy Clin Immunol 2001;107:3-8. Asthma management/medical professional and patient education: Facts About Controlling Your Asthma, NIH Publication No. 97-2339 Action Against Asthma: A Strategic Plan for the Department of Health and Human Services About asthma medications, American Lung Association
This page last reviewed September 28, 2004
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