The distribution of blood eosinophil count in the IMPACT South America population

Background: The Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2019 report stated that blood eosinophil count (BEC) may predict the magnitude of effect of inhaled corticosteroid (ICS) use in patients with COPD. A greater effect of ICS treatment on exacerbation reduction could be expected in patients with higher BEC. A controversy exists regarding the most clinically relevant threshold of BEC and how it could be affected in regions where the prevalence of atopy or parasitic infections might affect its distribution. Objective: Assess the distribution of BEC in the South America population of the Informing the Pathway of COPD Treatment (IMPACT) study. Methods: A sub-analysis of the IMPACT study, comprising the South America patient populationResults: South America population includes patients in Argentina (972), Chile (371), Peru (206), Brazil (108) and Colombia (51). Patients were 64% male and had a mean age of 65.6±8.4 years, BMI of 27.1±5.4 kg/m2, pre- and post-bronchodilator FEV1: 1.17±0.50 L and 1.25±0.51 L, respectively. Mean (±SD) BEC was 214±277 cells/µL and no significant differences were observed in the BEC distribution (mean, SD, median, quartiles) between countries (post hoc). These results suggest that baseline BEC in South America was very similar in magnitude to the overall intent-to-treat IMPACT population (222±234 cells/µL). Conclusions: BEC in the South America population of the IMPACT study was similar to that previously described in the total population. This supports the applicability of the IMPACT findings on eosinophils limits to the South America region. (Funding: GSK 116855) Method: COPD, Treatments All authors are GSK employees and stockholders.