Epidemiology of asthma

Disability-adjusted life year for asthma per 100,000 inhabitants in 2004.^[1]

no data   <100   100–150   150–200   200–250   250–300   300–350

350–400   400–450   450–500   500–550   550–600   >600

As of 2011, ~235 million people worldwide were affected by asthma,^[2] and approximately 250,000 people die per year from the disease.^[3] Low and middle income countries make up more than 80% of the mortality.^[4] Rates vary between countries with prevalences between 1 and 18%.^[3] It is more common in developed than developing countries.^[3] One thus sees lower rates in Asia, Eastern Europe and Africa.^[5] Within developed countries it is more common among those who are economically disadvantaged while in contrast in developing countries it is more common amongst the affluent.^[3] The reason for these differences is not well known.^[3]

While asthma is twice as common in boys as girls,^[3] severe asthma occurs at equal rates.^[6] In contrast adult women have a higher rate of asthma than men.^[3] Asthma is more common in the young than the old.^[5]

Increasing frequency

The prevalence of childhood asthma in the United States has increased since 1980, especially in younger children.

Rates of asthma have increased significantly between the 1960s and 2008^[7][8] with it being recognized as a major public health problem since the 1970s.^[5] Some 9% of US children had asthma in 2001, compared with just 3.6% in 1980. The World Health Organization (WHO) reports that some 10% of the Swiss population have asthma as of 2007, compared with 2% some 25–30 years ago.^[9] In the United States the age-adjusted prevalence of asthma increased from 7.3 to 8.2 percent during the years 2001 through 2009 .^[10]

Country specific data

Asthma affects approximately 7% of the population of the United States and causes approximately 4,210 deaths per year.^[11][12][13] In 2005, asthma affected more than 22 million people, including 6 million children, and accounted for nearly 500,000 hospitalizations that same year.^[14] In 2010, asthma accounted for more than one-quarter of admitted emergency department visits in the U.S. among children aged 1–9 years, and it was a frequent diagnosis among children aged 10–17 years.^[15] From 2000 through 2010, the rate of pediatric hospital stays for asthma declined from 165 to 130 per 100,000 population, respectively, whereas the rate for adults remained about 119 per 100,000 population.^[16]

Asthma prevalence in the U.S. is higher than in most other countries in the world, but varies drastically between ethnic populations.^[17] Asthma prevalence is highest in Puerto Ricans, African Americans, Filipinos, Irish Americans, and Native Hawaiians, and lowest in Mexicans and Koreans.^[18][19][20] Rates of asthma-related hospital admissions in 2010 were more than three times higher among African American children and two times higher for African American adults compared with White and Asian and Pacific Islander patients.^[16]

Asthma prevalence also differs between populations of the same ethnicity who are born and live in different places.^[21] U.S.-born Mexican populations, for example, have higher asthma rates than non-U.S. born Mexican populations that are living in the U.S.^[22]

Asthma affects approximately 5% of the United Kingdom’s population.^[23] In England, an estimated 261,400 people were newly diagnosed with asthma in 2005; 5.7 million people had an asthma diagnosis and were prescribed 32.6 million asthma-related prescriptions.^[24]

Notes

References