Interventions that Target Asthma Symptoms Show Promise

Comprehensive interventions to reduce asthma symptoms among children in low-income communities that were proven efficacious in randomized clinical trials (RCTs) have now been found effective in "real world" settings.

Closing the gap between proven efficacy and demonstrated effectiveness is often difficult to accomplish, according to the researchers of the CHAMPS (Community Healthcare for Asthma Management and Prevention of Symptoms) study.

"The path from these tightly controlled, efficacious RCTs to applied settings is often fraught with failure, especially when the real-world setting has limited intervention resources and personnel," lead author Suzanne Kennedy, PhD (pictured), of the Department of Pediatrics at North Carolina Children's Hospital, University of North Carolina, Chapel Hill, and colleagues observed.

The interventions were formulated by a consortium to investigate inner-city asthma convened by the National Institute of Allergy and Infectious Diseases. The investigators conducted large-scale epidemiologic studies to identify a variety of risk factors related to asthma morbidity ranging from difficulties accessing care to allergen sensitivities and inadequate understanding and avoidance of asthma triggers.

The intervention programs were then tested in 2 RCTs. The National Cooperative Inner-City Asthma Study (NCICAS) evaluated a program to identify each child's specific risk, elicited with the Child Asthma Risk Assessment Tool (CARAT), and apply tailored intervention modules. The Inner-City Asthma Study (ICAS) used an environmental risk assessment tool (ERAT) to identify environmental exposures and sensitivities and examined how remediation projects for each family affected the child's asthma symptoms.

The CHAMPS study conducted by Kennedy and colleagues selected community health centers in 3 high-risk, low-income communities, in Arizona, Michigan, and Puerto Rico. Each of these, as well as matched health center control sites, was a Federally Qualified Health Center participating in Medicaid. "Intervention sites were selected to have different levels of capacity to conduct the intervention to provide a robust assessment of the program's effectiveness,” the researchers explained.

Each health center was to recruit 100 children, ages 5 to 12 years, with moderate to severe asthma. The investigators met with site clinicians to consider strategies which would represent a "minimum agreed upon intervention."

Kennedy and colleagues noted the importance of adapting the clinical trial protocols to the varied resources and populations in the health centers while maintaining core treatment elements and outcomes. Their findings, they indicated, "supports the notion that it is the tailoring of the intervention, not only to the participant but to the site, that made CHAMPS effective."

The interventions included allergen sensitivity testing and exposure remediation, and 4 visits over the course of 1 year to evaluate adherence to treatment and course of symptoms. The primary outcome in CHAMPS was a reduction in maximum symptom days in the previous 4 weeks, in the most prominent of 3 symptoms: number of days with wheezing, tightness in chest or cough; the number of nights with sleep disturbed by asthma; the number of days asthma symptoms interfered with child's play activities.

Despite limited resources, each site accomplished the recruitment and retention goals, the core interventions, and at least 4 asthma counseling visits. After 1 year, the intervention children demonstrated significantly greater improvement than children at control sites. Notably, children at all 3 intervention sites had significantly fewer instances of urgent health care visits (53% intervention sites, 74% control sites). In addition, prednisone use among intervention children was reduced to approximately half of that required by control children.

"The study showed that clinical research interventions for a chronic disease can be successfully moved into practice," Kennedy and colleagues concluded.

The CHAMPS study report was published in the June issue of Pediatrics.