M28 How common is aspergillus sensitisation in COPD and is it related to frequent exacerbations?

Background

Chronic obstructive pulmonary disease (COPD) is characterised for many patients by periods of disease stability interspersed with periods of exacerbation. Biologics are emerging as a potential treatment for COPD patients with frequent exacerbations. Aspergillus sensitisation (AS) Is common in asthma however is often overlooked in COPD. We aim to investigate the prevalence of AS in a well described COPD cohort and its relationship to exacerbation frequency.

Methods

We conducted a cross-sectional analysis of clinical data with longitudinal exacerbation data from the London COPD cohort. We collected data from research visits conducted during disease stability between September 2023 and May 2024. Participants with a previous diagnosis of fungal pulmonary disease, or other active significant pulmonary disease were excluded. Blood samples were taken, COPD Assessment Test (CAT) scores were recorded and clinic spirometry was performed. We defined AS by aspergillus IgE ≥0.35 kUA/L and total IgE <500 kUA/L, and serological allergic bronchopulmonary aspergillosis (sABPA) as aspergillus IgE ≥0.35 kU/L and total IgE ≥500 kU/L. Continuous variables between groups were compared with the Mann-Whitney U test and proportions of discrete variables were compared with the Pearson's chi-squared test.

Results

There were 66 patients included (45 (68%) male, mean age 75 years (SD +/- 7) and 18% current smokers). Mean FEV1% predicted was 56 (SD +/- 21). In total 9 (13.6%) patients had AS and of those, 44% had ≥3 exacerbations in the preceding 12 months vs 14% in the non-AS group (p = 0.08). The mean CAT score was higher in the AS group (20 vs 17) although this was not statistically significant. Mean FEV1% predicted was similar in both groups. Two participants met criteria for sABPA. Eight participants had a blood eosinophil count ≥300 cells/µL (1 patient in the AS group vs 4 in the non-AS group). There was no correlation between eosinophil count and AS.

Conclusion

In our cohort AS is common and not related to eosinophil count, although numbers are small. AS may lead to more frequent COPD exacerbations and consideration should be given to screening for fungal disease in this group.