Predictive Properties of the Asthma Control Test and Its Component Questions for Severe Asthma Exacerbations

BACKGROUND: Current US guidelines recommend the Asthma Control Test (ACT) for assessing disease control and selecting treatment. OBJECTIVE: The goal of this study was to prospectively assess the ACT and its component questions for their utility in predicting the risk of severe asthma exacerbations. METHODS: Individuals were participants in the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity, and those included in the current analysis had the following characteristics: age 18 years or more, physician-diagnosed asthma, and longitudinal care received at a large health system in southeastern Michigan. Study participants underwent a baseline evaluation, which included answering the ACT. A severe asthma exacerbation was defined as one requiring oral steroids, an emergency department visit, or inpatient admission. Receiver-operator characteristic curves were used to measure and compare the predictive utility of the ACT and its component questions for severe asthma exacerbations. RESULTS: Of 1180 participants, 354 (30.0%) experienced a severe asthma exacerbation within 6 months of their baseline evaluation. When compared with the individual questions that composed the ACT, the composite score was significantly better at predicting severe exacerbations with 1 exception; the composite ACT score and the question assessing rescue medication use were not significantly different (P = .580). Pharmacy-based records of metered-dose inhaler short-acting beta-agonist use and asthma severity were also not significantly different from the composite ACT score. CONCLUSIONS: Our study demonstrates that although the ACT is modestly predictive for exacerbations, the composite score may not be superior to assessing rescue medication use alone for predicting the risk of severe asthma exacerbations

Predictive Properties of the Asthma Control Test and Its Component Questions for Severe Asthma Exacerbations

BACKGROUND: Current US guidelines recommend the Asthma Control Test (ACT) for assessing disease control and selecting treatment. OBJECTIVE: The goal of this study was to prospectively assess the ACT and its component questions for their utility in predicting the risk of severe asthma exacerbations. METHODS: Individuals were participants in the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-Ethnicity, and those included in the current analysis had the following characteristics: age 18 years or more, physician-diagnosed asthma, and longitudinal care received at a large health system in southeastern Michigan. Study participants underwent a baseline evaluation, which included answering the ACT. A severe asthma exacerbation was defined as one requiring oral steroids, an emergency department visit, or inpatient admission. Receiver-operator characteristic curves were used to measure and compare the predictive utility of the ACT and its component questions for severe asthma exacerbations. RESULTS: Of 1180 participants, 354 (30.0%) experienced a severe asthma exacerbation within 6 months of their baseline evaluation. When compared with the individual questions that composed the ACT, the composite score was significantly better at predicting severe exacerbations with 1 exception; the composite ACT score and the question assessing rescue medication use were not significantly different (P = .580). Pharmacy-based records of metered-dose inhaler short-acting beta-agonist use and asthma severity were also not significantly different from the composite ACT score. CONCLUSIONS: Our study demonstrates that although the ACT is modestly predictive for exacerbations, the composite score may not be superior to assessing rescue medication use alone for predicting the risk of severe asthma exacerbations

Assessing differences in inhaled corticosteroid response by self-reported race-ethnicity and genetic ancestry among asthmatic subjects

BACKGROUND: Inhaled corticosteroids (ICSs) are the preferred treatment for achieving asthma control. However, little is known regarding the factors contributing to treatment response and whether treatment response differs by population group. OBJECTIVE: We sought to assess behavioral, sociodemographic, and genetic factors related to ICS response among African American and European American subjects with asthma. METHODS: Study participants were part of the Study of Asthma Phenotypes and Pharmacogenomic Interactions by Race-ethnicity (SAPPHIRE). The analytic sample included asthmatic subjects aged 12 to 56 years with greater than 12% bronchodilator reversibility and percent predicted FEV1 of between 40% and 90%. Participants received 6 weeks of inhaled beclomethasone dipropionate. The primary measure of ICS response was a change in Asthma Control Test (ACT) score; the secondary measure was a change in prebronchodilator FEV1. Adherence was measured with electronic monitors. Genetic ancestry was estimated for African American participants by using genome-wide genotype data. RESULTS: There were 339 study participants; 242 self-identified as African American and 97 as European American. Baseline ACT score, percent predicted FEV1, degree of bronchodilator response, and ICS adherence were significantly associated with ICS response. A baseline ACT score of 19 or less was useful in identifying those who would respond, as evidenced by the significant dose-response relationship with ICS adherence. Neither self-reported race-ethnicity among all participants nor proportion of African ancestry among African American participants was associated with ICS responsiveness. CONCLUSIONS: Our findings suggest that baseline lung function measures and self-reported asthma control predict ICS response, whereas self-reported race-ethnicity and genetic ancestry do not