These study results appear in the second issue for January 2006 of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society.
Juan C. Celedón, M.D., Dr. P.H., of Channing Laboratory in Boston, Massachusetts, along with two associates, examined studies related to asthma and asthma rates in Hispanics in the United States, as well as in Hispanic America. In the article, the authors discuss the marked variation in the prevalence, state of disease and mortality associated with asthma among Hispanics.
Asthma is a condition in which the airways are narrowed as a result of hyperreactivity from certain stimuli that cause inflammation. The airway narrowing causes the person to exert more effort to move air in and out. However, drug treatment can open the airways and allow most asthmatics to lead relatively normal lives
Although data on U. S. Hispanics with asthma is limited, a study of 1,319 school children in East Harlem, New York, showed current wheezing was significantly more common in Puerto Ricans at 31 percent as compared with other ethnic groups (20.4 percent).
"According to the 2000 census, there were 35.2 million Hispanics in the United States, comprising approximately 12.5 percent of the population," said Dr. Celedón. "Between 1990 and 2000, the Hispanic population in the U.S. increased by 60.7 percent. Hispanics are the fastest growing minority in the United States, and, by 2050, their numbers are expected to triple, thus becoming 24.4 percent of the population."
Almost 60 percent of the Hispanics in the U.S. trace their roots to Mexico, with over 22 percent noting Puerto Rican, Central American, South American or Cuban ancestry. The balance, 18 percent, came from other countries such as the Dominican Republic. About 24 percent of Mexicans and over 25 percent of Puerto Ricans in the U.S. live below the poverty level (defined in 2002 as an annual income of $14,348 for three people).
"Asthma is a common health problem in Puerto Ricans living in the U.S. mainland and Puerto Rico," said Dr. Celedón. "In contrast, the prevalence of self-reported asthma is relatively low, but not negligible, given the large population size, in Mexican Americans."
Among participants in the Genetics of Asthma in Latinos study, Puerto Ricans, as compared with individuals of Mexican descent, had an earlier onset of the disease, lower lung function test results, and a higher risk of lifetime hospitalizations from asthma, plus more visits to the emergency room because of the disease during the previous year.
In a review of the vital statistics data, the age-adjusted annual asthma mortality rates (per 1 million persons) were 40.9 in Puerto Ricans, 38.1 in non-Hispanic blacks, 15.8 in Cuban Americans, 14.7 in non-Hispanic whites, and 9.2 in Mexican Americans.
A study of 17,555 Mexican-American adults showed that being born in the U.S. was associated with a two-fold increase in the odds of lifetime physician-diagnosed asthma. Yet among Mexican Americans born in Mexico, those living in the U.S. for at least 10 years had half the prevalence of asthma as those who had been in the country less than 10 years.
"The reasons for the differences in asthma and rate of disease, or morbidity, among and within Hispanic subgroups are poorly understood but are likely due to the interaction between yet-unidentified genetic variants and other factors, including environmental tobacco smoke exposure, obesity, allergen exposure and availability of health care," said Dr. Celedón.
He stressed that broadening access to health care, improving housing conditions and reducing exposure to environmental tobacco smoke along with a reduction in other indoor allergens would have a significant positive impact on asthma rates in poor Hispanics.
Contact: Juan C. Celedón, M.D., Dr. P.H.
Channing Laboratory, 181 Longwood Avenue, Boston, MA 02115
Phone: (617) 525-0958
E-mail: juan.celedon@channing.harvard.edu
For more information on asthma, visit the Asthma and Allergy Foundation of America's website at http://www.aafa.org/. A member of the American Thoracic Society's Public Advisory Roundtable, the Foundation offers a variety of material on disease diagnosis, treatment and management, as well as advocacy for more research.
Journal
American Journal of Respiratory and Critical Care Medicine