Yes, asthma has increased steadily in the United States through the 1980s and 1990s, as in other Westernized countries. There are more persons diagnosed with asthma now than ever before in the United States. The prevalence of asthma—that is the total number of cases of asthma in a population at any given point in time— continues to increase worldwide . It may also be true that allergic conditions are on the increase. The reason why asthma is increasing in the United States and in other industrialized nations is unclear.
A far-reaching international effort to understand the scope of increasing asthma (and allergy) in young people led in 1991 to the formation of the ambitious and ongoing International Study of Asthma and Allergies in Child-hood, known as ISAAC, and accessible on the Internet at Google. ISAAC describes itself as “the largest worldwide collaborative research pro-gram ever undertaken involving more than 100 countries and 2 million children.” Findings that have emerged from the ISAAC study include the observation that English-speaking countries demonstrate the highest prevalence rates for asthma and that Latin American countries also have elevated asthma rates.
Prevalence of Asthma: International Patterns
Asthma is increasing worldwide.
Asthma is generally more common in Western countries as com-pared to developing countries.
Asthma is more prevalent in English-speaking countries.
Asthma prevalence is increasing in developing countries as they become more urbanized and more “Westernized.”
There appears to be an accompanying increase in allergic diseases as well.
Of great concern to physicians are certain urban neighborhoods, such as the South Bronx and East Harlem in New York City, where rates of asthma hospitalization and asthma deaths are among the highest in the nation, and where nearly 20% of children have been diagnosed with asthma. When looking at “the big picture” however, U.S. data collected from 1980 to 1996 reveal, as mentioned previously, an increase in asthma prevalence. Since 1995, there have also been increases in national rates of office, clinic, and emergency room visits for asthma. Those increases developed in parallel with a decrease in the rates of hospitalization for asthma and of deaths from asthma. Experts believe that the increase in the number of outpatient visits is the result of better and more effective asthma treatment in the setting of increasing numbers of persons diagnosed with the disease. The recorded drop in hospital admissions for asthma and the reductions in the death rate are also consistent with improved asthma care overall—an encouraging public health statistic!
Gemma’s comment:
Is asthma more common in urban than rural areas? Environmental factors are very important in the city, but many of the triggers that plague urban environments may also be found in rural areas, such as volatile organic compounds (found in varnishes, aerosol sprays, household disinfectants, and similar products), peeling paint, mold, decaying wood in older buildings, not to mention the heavy smoke from those romantic wood fires that vacationers love to build when they go to the country.
My own childhood was spent in a small, midwestern town with no significant heavy industry or other causes of environmental pollution, yet it was marked for me by an annual parade of seasonal allergies, colds, and a perpetual, wheezing croup.