Exploring associations between nasal fluid inflammatory proteins and patient-reported symptom burden in respiratory...

Patient-reported outcome measures are widely used to assess symptom burden in respiratory disease, yet the extent to which symptom severity reflects underlying mucosal biology remains incompletely understood. Nasal fluid provides a non-invasive matrix for assessing airway inflammation within the unified airway framework.

In this exploratory study, nasal fluid samples were collected from 30 participants with heterogeneous respiratory conditions, and protein concentrations were measured using a multiplex immunoassay. Associations between protein concentrations and symptom burden, measured using the 22-item Sino-Nasal Outcome Test (SNOT-22), were assessed using Spearman correlations.

Protein concentrations of 40 analytes were measured and were found to span a wide dynamic range across participants. The mean SNOT-22 score was 39.1 (range, 3-89). TRAIL and CXCL10 demonstrated positive correlations with SNOT-22 scores (rho = 0.563, p = 0.001 and rho = 0.520, p = 0.005, respectively). Heatmap analysis revealed marked inter-individual variability in nasal fluid protein expression, including among participants with similar SNOT-22 scores.

These findings demonstrate the feasibility of linking non-invasive nasal fluid biomarkers with composite symptom scores in a heterogeneous respiratory cohort. Together, they support the potential of nasal fluid profiling to capture clinically relevant biological variation and inform larger, multimodal studies integrating complementary clinical and physiological measures.