ASTHMA WATCH

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Children?s Asthma Not Under Control
A recent study shows that only 20% of children with persistent asthma have a level of control that is considered optimal. A study was conducted by the University of Rochester Medical Center in New York, and researchers analyzed data taken from a survey of parents of 975 children with asthma in 4 states across the country. The results were surprising, in light of the effectiveness of current therapies, according to Jill Halterman, MD, MPh, associate professor of pediatrics at the university, who led the study. ?That leaves almost 80% who are suffering more than they need to,? she said.

Current guidelines recommend that all children with persistent asthma?half of the 9.4% of all children with asthma?are prescribed anti-inflammatory medication. The study showed, however, that 37% of these children were receiving no preventive medication, and 43% of those who were receiving medicine were still troubled by poor symptom control. The findings were published in the March issue of Ambulatory Pediatrics.

New Heat Therapy Helps Asthma Patients
A new therapy that removes muscle tissue in the overly active airways of asthma patients by exposing it to heat has been shown to help improve the control of moderate-to-severe persistent asthma. The smooth-muscle fibers that surround the airways are the cause of airway constriction in asthma. The therapy, known as bronchial thermoplasty, aims to reduce these muscles? activity by delivering thermal energy to the walls of the airways. The therapy is administered with a bronchoscope and a heat-generating device at the end.

Researchers at McMaster University in Hamilton, Ontario, Canada, assessed the outcomes of 112 asthma patients who were randomly assigned to receive either bronchial thermo-plasty or standard care. They found that patients in the ther-moplasty group experienced a significant drop in flare-ups, compared with no change in the flare-up rate in the control group. The researchers? report appeared in the March 29, 2007, issue of the New England Journal of Medicine.

At the 12-month mark, the thermoplasty group reported significantly greater improvements in lung function and quality of life. They also had more days free of asthma symptoms and used less rescue medication. Because of the effort involved, short-term adverse effects, and probable expense, however, the procedure will probably need to be refined before it becomes more widely available.

The Hair of the Dog May Be Asthma Trigger
Researchers in California completed a study that suggests that having a dog in the house may worsen the symptoms in children with asthma by aggravating their response to air pollution. Living with cats, however, had no discernible effect. The results of the study appeared in the December 2006 issue of Environmental Health Perspectives.

The investigators recruited 3227 children from schools in 12 California communities. Of these, 475 had asthma. They completed health questionnaires and were studied over a 3-year period. They reported information each year on chronic cough and other lung symptoms. Data were also gathered regarding the families? socioeconomic status, pet ownership, and history of asthma in either parent. Of the children in the study, 62% had a dog in the home, and 43% had a cat. Using data from air pollution monitoring stations in each community, the researchers found that the association of air pollution with asthmatic symptoms was consistently greater in children who lived with dogs.

Although the exact cause of this effect is not clear, the researchers indicated that the evidence is not sufficient to suggest advising parents to remove dogs from the home. ?We need to understand what it is about dogs that results in this triggering effect,? said lead author Rob S. McConnell, MD.

Florida?s Red Tide: No Vacation for Asthma Patients
New research shows that asthma patients who spend just 1 hour on a beach in Florida during a red tide can experience a 10% drop in lung function and a flare-up of asthma symptoms. In addition, it may take up to 5 days for these patients to recover from this short amount of exposure. Every year, harmful algae known as Karenia brevis multiply in the Gulf of Mexico and wash ashore in Florida, sometimes causing the water to turn a brownish color and almost always causing a terrible fish odor, caused by the numerous fish killed off by the algae.

Researchers from the University of Miami Miller School of Medicine recruited 97 people aged 12 years and older with asthma to spend time on a Florida beach when the algae were in bloom. The participants were monitored before going to the beach and soon after they spent an hour walking on the beach during the red tide. Compared with walking on the beach when no algae were present, the participants were more likely to report respiratory symptoms and had a small, but significant, drop in lung function during the red tide.

Although the researchers are not sure what causes this reaction in asthma patients, they noted that the algae cause watery eyes and noses and a cough in people without asthma, and they suspect that the algae act as an irritant or allergen. The findings were published in the January 2007 issue of Chest.