Small-Airway Function Variables in Spirometry, Fractional Exhaled Nitric Oxide, and Circulating Eosinophils Predicted Airway Hyperresponsiveness in Patients with Mild Asthma.

PURPOSE: Patients with variable symptoms suggestive of asthma but with normal forced expiratory volume in 1 second (FEV1) often fail to be diagnosed without a bronchial provocation test, but the test is expensive, time-consuming, risky, and not readily available in all clinical settings. PATIENTS AND METHODS: A cross-sectional study was performed in 692 patients with FEV1≥80% predicted; normal neutrophils and chest high-resolution computed tomography; and recurrent dyspnea, cough, wheeze, and chest tightness. RESULTS: Compared with subjects negative for AHR (n=522), subjects positive for AHR (n=170) showed increased FENO values, peripheral eosinophils (EOS), and R5-R20; decreased FEV1, FEV1/Forced vital capacity (FVC), and forced expiratory flow (FEFs) (P≤.001 for all). Small-airway dysfunction was identified in 104 AHR+ patients (61.17%), and 132 AHR- patients (25.29%) (P<0.001). The areas under the curve (AUCs) of variables used singly for an AHR diagnosis were lower than 0.77. Using joint models of FEF50%, FEF75%, or FEF25%-75% with FENO increased the AUCs to 0.845, 0.824, and 0.844, respectively, significantly higher than univariate AUCs (P <0.001 for all). Patients who reported chest tightness (n=75) had lower FEFs than patients who did not (P<0.001 for all). In subjects with chest tightness, the combination of FEF50% or FEF25%-75% with EOS also increased the AUCs substantially, to 0.815 and 0.816, respectively (P <0.001 for all versus the univariate AUCs). CONCLUSION: FENO combined with FEF50% and FEF25%-75% predict AHR in patients with normal FEV1. FEF25%-75%, FEF50%, or FEF25%-75% together with EOS also can potentially suggest asthma in patients with chest tightness.

Prevalence and screening of specific aeroallergens in Chinese male patients with chronic obstructive pulmonary disease: A retrospective cross-sectional observational study.

INTRODUCTION: Sensitization to aeroallergens was linked to severe symptoms and frequent exacerbations in chronic obstructive pulmonary disease (COPD) patients. Elevated serum total immunoglobulin E (tIgE) level is a hallmark of allergic COPD patients. Phadiatop test exhibited high sensitivity for predicting specific aeroallergens (SAs) sensitization. However, the prevalence of aeroallergens, the value of Phadiatop test, alone or combined with tIgE, for predicting aeroallergens sensitization in male COPD patients have not been explored in China. OBJECTIVES: To explore the prevalence and predictors of aeroallergens in the context of COPD. METHODS: The predictive value of Phadiatop test for SAs sensitization in male COPD patients was analyzed via the area under receiver operating characteristic curves (AUCs). RESULTS: The top five SAs in the context of COPD were d2, mx2, i6, d1, and tx5, of which the seasonal distribution showed no significant differences. Allergic group showed higher levels of blood eosinophils, total Phadiatop IgE and tIgE than the nonallergic group (all P ≤ 0.001). The AUCs of total Phadiatop IgE and tIgE for predicting the sensitization to SAs, SAs excluding mx2 (AEM) and mx2 were ((0.921 vs. 0.879, P = 0.2522), (0.967 vs. 0.807, P = 0.0003), and (0.780 vs. 0.883, P < 0.05)) (AUCPhadiatop vs AUCtIgE ), respectively. The combined application of these two parameters (model) increased the AUC of SAs, significantly higher than the single parameter used (P < 0.05 for all). CONCLUSION: d2, mx2, i6, and d1 were the top four SAs sensitized in male COPD patients; Phadiatop test was valuable for predicting the sensitization to SAs when it was > 0.13 kAU/L.

The Value of Fractional Exhaled Nitric Oxide and Forced Mid-Expiratory Flow as Predictive Markers of Bronchial Hyperresponsiveness in Adults with Chronic Cough.

BACKGROUND: Bronchial provocation tests are standard for diagnosing the etiology of chronic cough, but they are time consuming and can induce severe bronchospasm. A safer and faster clinical examination to predict bronchial hyperresponsiveness (BHR) is needed. OBJECTIVE: The objective of this study was to investigate whether small-airway function tests can predict BHR in adult patients with chronic cough. METHODS: A retrospective, cross-sectional study of diagnoses made using spirometry and bronchial provocation test results was performed in 290 patients with chronic nonproductive cough. BHR-predictive values were analyzed via the area under receiver operating characteristic curves (AUCs). Optimal cutoff values were determined by maximizing the sum of sensitivity and specificity. RESULTS: Patients with chronic cough with BHR showed lower forced expiratory flow between 25% and 75% (FEF25%-75%), higher fractional exhaled nitric oxide (FENO), and a higher percentage of eosinophils in blood than patients without BHR (P < .0001 for all). The AUCs of FENO and FEF25%-75% for a BHR diagnosis were 0.788 (95% CI, 0.725-0.851) and 0.702 (95% CI, 0.641-0.763), respectively. Optimal cutoff values were 43 ppb for FENO and 78.5% for FEF25%-75%, with negative predictive values of 85.38% and 81.34%, respectively. The combined use of FENO and FEF25%-75% increased the AUC to 0.843 (95% CI, 0.794-0.892), significantly higher than either FENO (P = .012) or FEF25%-75% (P < .0001) alone. CONCLUSIONS: Small-airway dysfunction is present in patients with chronic cough and BHR. FEF25%-75% has value as a negative predictive parameter for BHR, especially when combined with FENO. FENO > 43 ppb and FEF25%-75% < 78.5% strongly predicted a positive bronchial provocation test.