Asthma prevalence jump alarms health experts

By Dr. Ananya Mandal, MDMay 4 2011

According to the Centers for Disease Control and Prevention (CDC) in a report released this Tuesday, Americans are suffering from asthma in record numbers. Nearly one in 10 children and almost one in 12 Americans of all ages now has asthma, government researchers said. Tuesday was World Asthma Day.

The report that spans over 2001 to 2009 showed that the prevalence of asthma increased among all demographic groups studied, including men, women, whites, blacks and Hispanics. Black children are most acutely affected: the study found that 17 percent of black children - nearly one in five - had a diagnosis of asthma in 2009, up from 11.4 percent, or about one in nine, in 2001.

Health experts at the CDC emphasized that asthma could be controlled if managed effectively, they were at a loss to explain why it had become more widespread even as important triggers like cigarette smoking had become less common. “We don’t know exactly why the number is going up, but, importantly, we know there are measures individuals with asthma can take to control symptoms,” said Ileana Arias, principal deputy director of the centers.

They suggested that prevention depends on educating patients about appropriate use of medications and ensuring that each patient has a written medical plan to control asthma, but the report found that only one-third of patients had been given a plan and only about half had been advised to make changes to eliminate asthma triggers at home, school and work.

According to Paul Garbe, chief of the Air Pollution and Respiratory Health Branch at the centers, the success of several state public health initiatives, including one in Connecticut in which asthma educators and environmental assessors were sent into homes to advise patients on what changes needed to be made and how to manage the disease.

The report says that overall prevalence of asthma increased to 8.2 percent in 2009, when 24.6 million cases were diagnosed, from 7.3 percent in 2001, when 20.1 million cases were diagnosed. The latter rise was 12.3%. Among the most affected were children, 9.6 percent of whom had asthma, and especially poor children, of whom 13.5 percent had it. While 7.7 percent of adults were found to have asthma, the rate was higher among women (9.7 percent) and among poor adults of both sexes (10.6 percent).

Analyzing cost of therapy the report said that asthma costs grew to about $56 billion in 2007, up from about $53 billion in 2002. However annual deaths attributed to asthma declined to about 3,500 in 2007, from a peak of about 5,500 deaths in 1996.

The next steps would be to investigate several potential causes for the increase in asthma, including exposure to various allergens, traffic exhaust fumes, pesticides and certain plastics, as well as factors like obesity and diet that may play a role, said Dr. Rachel L. Miller, director of the asthma project at the Mailman School of Public Health at Columbia University. “There’s no easy singular explanation,” Dr. Miller said. “The more we study this, the more it raises a lot of questions. It’s not a straightforward puzzle at all.”