Elevated Serum Levels of Herpes Virus Entry Mediator and IL-5 in Cough Variant Asthma Versus Classic Asthma Patients

Abstract BackgroundCough variant asthma (CVA) is a special phenotype of asthma. The precise inflammatory features of patients with CVA, however, is still unclear. We aimed to elucidate the differential inflammatory features in patients with CVA in contrast to patients with classic asthma (CA). MethodsA total of 68 patients with persistent uncontrolled asthma (34 with CVA, 34 with CA) in Shenzhen People’s Hospital between August 2018 and May 2019 were enrolled. We collected the demographic data, pulmonary function test (PFT) parameters, hematological variables, and several serum biomarkers. Receiver operating characteristic (ROC) curves were generated to evaluate the values of biomarkers for distinguishing between CVA and CA. ResultsCompared with CA group, CVA group had a higher percentage of females (73.5 vs. 50%, P = 0.046), lower proportion of asthma family history (5.9 vs. 29.4%, P = 0.011), shorter disease course [12.0 (4.8, 39) vs. 96.0 (48.0, 240.0) months, P < 0.001], and better pulmonary function (P all < 0.05). Increased levels of blood eosinophil count [0.35 (0.13, 0.94) vs. 0.34 (0.01, 0.53) X109/L, P = 0.045], eosinophil percentage [6.3 (3.0, 9.8) vs. 4.4 (0.2, 8.4) %, P = 0.046], serum IL-5 [104.19 (89.03, 199.66) vs. 84.57 (26.87, 103.58) ng/L, P = 0.011], and serum herpesvirus entry mediator (HVEM) [128.53 (100.89, 204.83) vs. 90.71 (37.05, 108.08) pg/mL, P = 0.002] were also found in CVA patients compared to those in CA patients. The logistic analysis revealed that serum HVEM had a strong predictive power for CVA group (OR = 1.105, P = 0.015). The sensitivities and specificity of serum HVEM and IL-5 to distinguish between CVA and CA at optimal cut-offs were 85.0% and 61.1%; 85.0% and 61.1%, respectively. AUCs of serum HVEM and IL-5 were 0.789 and 0.739, respectively. Furthermore, serum HVEM and IL-5 had no correlation with PFT parameters in CVA group (P all > 0.05).ConclusionsElevated serum levels of HVEM and IL-5 are exhibited in CVA patients, which may indicate their important roles in the pathogenesis and progression of CVA.