A new marker of eosinophilic inflammation in patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is one of the most common bronchopulmonary diseases. Eosinophilic inflammation of the respiratory tract in COPD requires further search for new markers for diagnosis and determination of further therapy strategy. Aim: determination of periostin level and assessment of its significance as a marker of eosinophilic inflammation in patients with COPD. The study included 45 patients with COPD (males at median age of 65). Medical history, results of clinical and instrumental studies were evaluated. The levels of total IgE and periostin were determined in blood serum by enzyme immunoassay. The obtained data were processed using the software systems STATISTICA 13 and SPSS Statistical 27. On the basis of peripheral blood eosinophils, the patients were divided into a group with eosinophilic inflammatory endotype (9 patients, males aged 67), and a non-eosinophilic endotype (36 patients, men aged 65 years). The patients with eosinophilic endotype of COPD had a later onset of the disease [64 (61-65) years vs 56 (49-60); p = 0.011], and a significantly higher proportion of patients with a history of atopy (80% vs 0%; p 0.001). In patients with non-eosinophilic COPD endotype, a significantly lower FEV1/FVC index was found [46 (44-51) % vs 54 (54-73) %; p = 0.019]. The serum periostin level in patients with the eosinophilic endotype of COPD was 21 (20-22) ng/mL thus being significantly higher than in the group with the non-eosinophilic endotype [14.5 (12-18) ng/mL; p = 0.008]. Using ROC analysis, it was found that a periostin value of more than 19.5 ng/mL is the optimal cut-off point for detecting the eosinophilic endotype in patients with COPD thus serving an additional potential predictor of a positive response to inhaled glucocorticosteroid therapy (ICS) [AUC was 0.940 ± 0.060 with 95% CI: 0.822-1,000, sensitivity of 80%, specificity of 80% (p = 0.007)]. Periostin is a promising marker of eosinophilic inflammation in patients with COPD. Its elevated level may be considered an additional criterion for the administration of ICS therapy.