The prevalence of asthma in children living in the suburbs is becoming more common, challenging the theory that asthma is a problem exclusive to inner city children.

A new Johns Hopkins Children's Center study also found that low family income and being African American or Puerto Rican had a stronger influence on asthma risk than overall neighborhood poverty.

The study was based on a survey of parents and caregivers of 23,065 children, ages 6 to 17 and showed that 13 percent of inner-city kids had asthma, with an 11 percent rate of asthma for children living outside of inner cities.

In an interview with Latin Post, Dr. Elizabeth Matsui, a pediatric asthma specialist and associate professor of pediatrics and epidemiology at the Johns Hopkins University School of Medicine and senior study author said, "The reason we see high rates of asthma outside of poor urban areas is because people of color and lower socioeconomic status have left the urban areas in the past decade or so and are more likely to live in suburban areas than in small towns.

More than 50 years ago, public health experts began seeing an epidemic of inner-city asthma cases. The idea was that certain aspects of urban living -- higher rates of premature births, cockroach and other pest allergens, poor diet, lack of exercise and stress -- make inner-city children more prone to developing asthma.

The study found that African-American children and those of Puerto Rican descent had disproportionately higher asthma rates, at 17 and 20 percent respectively, compared with their white (10 percent), other Hispanic (9 percent) and Asian (8 percent) counterparts. According to the authors, this study confirms previous data which indicate that being African American or Puerto Rican remained potent risk factors even after the scientists eliminated the influence of other variables such as neighborhood poverty, household income and geographic area of residence.

"What we do know from our study and others is that Puerto Ricans in the U.S. have the highest prevalence," said Matsui." How much of that is genetics or acculturation is not clear."

Researchers found that the prevalence of asthma in low-income suburban areas of the Northeast was 21 percent, compared with 17 percent in the corresponding urban area of that same geographic region. In the Midwest, there was a 26 percent asthma prevalence in medium metro areas, compared with 15 percent in urban areas.

"The take home message is that there may be more asthma than was recognized before in those areas outside of poor urban communities," said Matsui. "The individual clinician should have her antenna up about a child having asthma because it's the most common chronic disease of childhood."