The level of asthma control incorporates current clinical control and exacerbations. Traditionally asthma treatments have been individualized using symptoms and spirometry or peak flow. Biomarkers hold promise for capturing complementary information, but need to be validated with regard to control. Two studies published online ahead of print in Thorax may help to give some guidance in clinical practice.
First, a systematic review evaluated the efficacy of tailoring asthma interventions based on inflammatory markers (sputum analysis and FeNO) as compared to clinical symptoms with or without pulmonary function tests in children and adults (Petsky et al. Thorax, 11 Oct 2010, epub ahead of print). The authors concluded that “tailoring of asthma treatment based on sputum eosinophils (3 studies in adults) is effective in decreasing asthma exacerbations in adults. However, tailoring of asthma treatment based on FeNO levels (2 studies in adults and 4 in children) has not been shown to be effective in improving asthma outcomes in children and adults.”
In the second article, a study was undertaken to investigate whether a strategy based on sputum eosinophils would be successful in 55 children with severe asthma (Fleming et al. Thorax, 8 August 2011, epub ahead of print). “Incorporating the control of sputum eosinophils into the management algorithm,” the authors concluded, “did not significantly reduce overall exacerbations or improve asthma control. Exacerbations were reduced in the short term, suggesting that more frequent measurements would be needed for a clinically useful effect and that controlling inflammation may have a role to play in subgroups of children with severe asthma.”
Do you agree that biomarkers are either not readily available or unavailable in most practice settings?