Reference values for blood eosinophil counts in a population-representative adult sample

<bold>Background:</bold> Assessing blood eosinophil count (BEC) as a prognostic biomarker is challenging due to the lack of known normal BEC values in the general population. <bold>Aim:</bold> To determine reference values for BEC in a random adult sample. <bold>Methods:</bold> The West Sweden Asthma Study is a clinical epidemiological population-representative cohort of randomly selected individuals living in Western Sweden. From this cohort, 2,000 participants were invited to clinical examinations including assessment of allergic sensitization and BEC, of which 1,145 participated. Clinical allergy was defined as the co-occurrence of sensitization and self-reported allergic symptoms to a specific allergen family. <bold>Results:</bold> Age, asthma, chronic obstructive pulmonary disease (COPD), and clinical allergy altered the mean, median, and 95^th percentiles of BEC values, as shown in <bold>Figure 1</bold> and <bold>Table 1</bold>. <bold>Conclusions:</bold> In a population-representative sample, the 95^th percentile of BEC, as opposed to the 75^th percentile, showed heightened vulnerability to diverse modifications, such as asthma, COPD, and clinical allergy, rising from 300 to 400 cell/μL with age in a subgroup devoid of these factors. <fig><object-id>erj;64/suppl_68/OA1863/F1</object-id><object-id>F1</object-id><object-id>F1</object-id><graphic></graphic></fig> <fig><object-id>erj;64/suppl_68/OA1863/F2</object-id><object-id>F2</object-id><object-id>F2</object-id><graphic></graphic></fig>