Asthma prevalence reached its highest level ever in 2010 -- 8.4% of the population, up from 7.3% in 2001, according to the CDC.
That translates into 18.7 million adults and 7 million children who had been diagnosed with asthma and still had the condition in 2010, the agency said in a report called Asthma's Impact on the Nation.
In 2009, asthma accounted for 3,388 deaths, 479,300 hospital admissions, 1.9 million emergency department visits, and 8.9 million visits to doctors' offices.
On the other hand, the agency reported, deaths from the disease have been declining from 2001 through 2009, as have visits for asthma to physician offices and hospital outpatient departments.
The death rate per 1,000 people with asthma was 0.14 in 2009, down from 0.21 in 2001, while the rate of primary care encounters was 47.8 per 100 asthma patients in 2009, down from 61.9 in 2001.
Hospital admissions and emergency room visits have been stable, the agency reported. The 2009 rates per 100 asthma patients were 8.4 and 2.0, respectively.
Asthma costs the U.S. $56 billion a year, with the average yearly cost of care for a child with asthma reaching $1,039 in 2009, the CDC reported.
The findings are "a stark reminder that asthma continues to be a major public health concern," commented Christopher Portier, PhD, director of the agency's National Center for Environmental Health and the Agency for Toxic Substances and Disease Registry. The illness has "a large financial impact on families, the nation, and our health care system," he said in a statement.
The analysis includes the first state-by-state data gathered using the CDC's Asthma Call-back Survey, conducted among people with asthma identified by the CDC Behavioral Risk Factor Surveillance System.
The CDC also found that asthma prevalence was higher among children, females, and the poor over the period 2008 through 2011.
- Among those 17 and under, the prevalence was 9.5%, compared with 7.7% for those 18 and over.
- The rate among females was 9.2%, compared with 7% among males.
- Among people with incomes below the poverty line, asthma prevalence was 11.2%, compared with 8.7% for those with incomes up to twice the poverty line, and 7.3% for people whose incomes were more than twice the poverty line.
Rates also differed along racial and ethnic lines, the agency reported.
The highest rate was among people who described themselves as multiracial and the lowest rate was among people of Asian descent -- 14.1% and 5.2%, respectively.
In between were blacks at 11.2%, American Indian or Alaska Natives at 9.4%, whites at 7.7%, and Hispanics at 6.5%.
Interestingly, among Hispanics, asthma prevalence was higher among people of Puerto Rican than among those of Mexican descent -- 16.1% versus 5.4%.
The study was conducted by the CDC. Authors are employees of the agency.
National Center for Health Statistics.Source Reference: Akinbami LJ, et al "Trends in asthma prevalence, health care use, and mortality in the United States, 2001–2010" NCHS 2012;94.