D3.143 - Immunomodulatory role of vitamin D in severe asthma: a potential biomarker of treatment response

Severe asthma represents a heterogeneous and complex clinical challenge that remains poorly controlled despite oooomal standard therapy, often requiring the use of biological drugs targeting specific inflammatory pathways. There is growing evidence that nutritional and metabolic factors, including vitamin D status, can modulate the immune response and potentially influence the effectiveness of biological therapy. Given the immunomodulatory role of vitamin D, investigating its association with treatment outcomes in patients with severe asthma is becoming increasingly important. The aim of this study was to investigate the association between baseline vitamin D levels and changes in clinical and inflammatory parameters following the introduction of biological therapy in patients with severe asthma, with a particular focus on the subjective assessment of disease control (ACQ questionnaire).

A retrospective analysis included 165 patients with severe asthma treated with biological therapy. Data on baseline vitamin D levels and changes in the following parameters were analyzed: FEV1, ACQ, CRP, eosinophils, neutrophils, FeNO, and the use of oral corticosteroids.

A statistically significant positive correlation was found between baseline vitamin D levels and improvement in ACQ scores (ρ = 0.221; p = 0.036), suggesting that patients with higher baseline vitamin D levels experienced greater subjective improvement in disease control. No statistically significant correlations were observed between vitamin D levels and changes in FEV1 (p=0,063), CRP (p=0,390), eosinophils (p=0,220), neutrophils (p=0,686), FeNO (p=0,837), or changes in oral corticosteroid use (p =0,154). Additionally, body mass index showed no association with vitamin D levels (p= 0,862).

Baseline vitamin D levels showed a statistically significant association with subjective disease control improvement (ACQ), while no association with objective clinical and inflammatory parameters was confirmed. Nevertheless, considering existing evidence from previous studies on the vitamin D role in modulating immune responses and its potential to reduce the frequency of asthma exacerbations, these results further support the importance of assessing and optimizing vitamin D status as part of a personalized approach to the treatment of severe asthma. Further studies are needed to more precisely determine its therapeutic potential.