Expired Nitric Oxide and Airway Obstruction in Asthma Patients with an Acute Exacerbation

Abstract Background Capnography waveform contains essential information regarding physiological characteristics of the airway and thus indicative of the level of airway obstruction. Our aim was to develop a capnography-based, point-of-care tool that can estimate the level of obstruction in patients with asthma and COPD. Methods Two prospective observational studies conducted between September 2016 and May 2018 at Rabin Medical Center, Israel, included healthy, asthma and COPD patient groups. Each patient underwent spirometry test and continuous capnography, as part of, either methacholine challenge test for asthma diagnosis or bronchodilator reversibility test for asthma and COPD routine evaluation. Continuous capnography signal, divided into single breaths waveforms, were analyzed to identify waveform features, to create a predictive model for FEV1 using an artificial neural network. The gold standard for comparison was FEV1 measured with spirometry. Measurements and main results Overall 160 patients analyzed. Model prediction included 32/88 waveform features and three demographic features (age, gender and height). The model showed excellent correlation with FEV1 (R = 0.84), R2 achieved was 0.7 with mean square error of 0.13. Conclusion In this study we have developed a model to evaluate FEV1 in asthma and COPD patients. Using this model, as a point-of-care tool, we can evaluate the airway obstruction level without reliance on patient cooperation. Moreover, continuous FEV1 monitoring can identify disease fluctuations, response to treatment and guide therapy. Trial registration clinical trials.gov, NCT02805114. Registered 17 June 2016, https://clinicaltrials.gov/ct2/show/NCT02805114

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Risk Factors Associated with Irreversible Airway Obstruction in Asthma: A Systematic Review and Meta-Analysis

BioMed Research International ◽

10.1155/2016/9868704 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 2

Author(s):

Lanlan Zhang ◽

Lixiu He ◽

Jin Gong ◽

Chuntao Liu

Keyword(s):

Risk Factors ◽

Systematic Review ◽

Atopic Dermatitis ◽

Airway Obstruction ◽

Fixed Effects ◽

Meta Analysis ◽

Case Control Studies ◽

Smoking Exposure ◽

Asthma Patients ◽

Irreversible Airway Obstruction

Irreversible airway obstruction (IAO) is a subtype of asthma and relates to poorer prognosis in some asthma patients. However, the prevalence and risk factors for IAO are unknown. A systematic review regarding controlled clinical studies (cohort, case-control studies) on IAO asthma in adult and/or children affected by asthma/early wheeze was performed. Eighteen papers were identified in this study. It was reported that the incidence of IAO at random effects or fixed effects in severe asthma and nonsevere asthma was 0.54 (95% CI: 0.45–0.62) and 0.16 (95% CI: 0.12–0.20), respectively. In IAO asthma, the pooled odds ratio (OR) related to smoking exposure was 2.22 (95% CI: 1.82–2.73), the OR for male, smoking, and fractional exhaled nitric oxide (FENO) was 2.22 (95% CI: 1.82–2.7), 1.79 (95% CI: 1.46–2.19), and 2.16 (95% CI: 1.05–4.43), respectively, suggesting these factors increase the risk of IAO. However, a decreased OR in IAO asthma was observed due to rhinitis (OR = 0.31, 95% CI: 0.24–0.40), atopy (OR = 0.584, 95% CI: 0.466–0.732), and atopic dermatitis (OR = 0.60, 95% CI: 0.42–0.85), indicating these factors are associated with reduced risk of IAO. IAO in asthma is associated with gender, smoking, FENO, rhinitis, atopy, and atopic dermatitis.

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The efficacy of the combination of exhaled nitric oxide and blood eosinophil count in the diagnosis of asthma in China

10.21203/rs.3.rs-89700/v1 ◽

2020 ◽

Author(s):

Jiang-hua Li ◽

Rui Han ◽

Yu-bo Wang ◽

Min Cheng ◽

Heng-yi Chen ◽

...

Keyword(s):

Nitric Oxide ◽

Characteristic Curve ◽

Positive Likelihood Ratio ◽

Exhaled Nitric Oxide ◽

Airflow Limitation ◽

Blood Eosinophil ◽

Asthma Diagnosis ◽

Diagnostic Efficacy ◽

Asthma Patients ◽

In Series

Abstract BackgroundTests to identify reversible airflow limitation are important in asthma diagnosis, but they are time-consuming and may be difficult for patients to cooperate. We aim to evaluate the predictive value of fractional exhaled nitric oxide (FeNO) and blood eosinophil (B-Eos) count in asthma diagnosis, and to distinguish patients who could avoid reversibility testing.MethodsWe screened 7463 suspected asthma cases between January 2014 and December 2019 in Chongqing, China, and identified 2349 patients with complete FeNO, B-Eos count, and spirometry data. Of these, 824 were diagnosed with asthma via a positive bronchial-provocation or bronchodilation test.ResultsWhen FeNO and B-Eos counts were used in combination, the area under the receiver operating characteristic curve (AUC) for diagnosing asthma increased (0.768 vs. 0.745 or 0.728; both P < 0.001). The odds ratio for having asthma increased progressively with a gradual increase in FeNO or B-Eos count (both P < 0.001). Further analysis of in-series combinations of different threshold values for these biomarkers indicated that moderately elevated biomarker levels (FeNO > 40 ppb and B-Eos > 300 cells/μl) support a diagnosis of asthma because diagnostic specificity was > 95% and the positive likelihood ratio (PLR) was > 10. This conclusion was verified when selecting the data from 2017 to 2019 as the verification cohort.ConclusionThe combination of FeNO and B-Eos count can improve diagnostic efficacy for asthma. Patients with moderately elevated biomarkers (FeNO > 40 ppb and B-Eos > 300 cells/μl) could be diagnosed with asthma.

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Can nasal nitric oxide be a biomarker to differentiate allergic and non-allergic rhinitis?

The Egyptian Journal of Otolaryngology ◽

10.1186/s43163-021-00154-1 ◽

2021 ◽

Vol 37 (1) ◽

Author(s):

A. F. Kalpaklioglu ◽

A. Baccioglu ◽

S. A. Yalim

Keyword(s):

Nitric Oxide ◽

Allergic Rhinitis ◽

Severe Disease ◽

Female Gender ◽

Non Invasive ◽

Nasal Nitric Oxide ◽

Nasal Symptoms ◽

Asthma Patients ◽

Duration Of Disease ◽

Non Allergic Rhinitis

Abstract Background Nasal nitric oxide (nNO), a noninvasive indicator for eosinophilic airway inflammation, has not been adequately studied in different types of rhinitis. The aim of this study was to compare nNO levels between allergic (AR) and non-allergic rhinitis (NAR). Patients were included based on their chronic nasal symptoms. Total nasal symptoms score (TNSS) were evaluated. nNO was measured transnasally with a flow of 5 ml/s from the nostril with an NO analyzer (NIOX MINO; Aerocrine, Sweden). Results were evaluated as parts per billion (ppb). Results Four hundred forty-three patients (277 F/166 M)—337 with AR (76%) and 106 with NAR (24%)—were assessed. Patients with AR had significantly higher TNSS, more severe disease, and longer duration of disease compared to NAR group. Allergic rhinitis had significantly higher nNO levels than NAR (370 ppb vs 290 ppb) (p = 0.001). Likewise, significant differences were observed in female gender, in patients with BMI ≥ 25 kg/m2 and those without sinusitis between the two groups. When nNO were further evaluated in comorbid asthma, patients with AR w/o asthma had the highest TNSS and had significantly higher nNO level (p < 0.001). NAR+A group, with the longest duration of rhinitis, was significantly older and had the lowest nNO level (p < 0.001). Conclusions This study showed that nNO levels were significantly higher in AR patients than NAR. Although there is no recommended standard threshold for nNO, this study confirmed the utility of nNO in differentiating AR and NAR in addition to its known fast and non-invasive advantages.

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The Utility of Serum IL-1β and CRP Together with Fractional Exhaled Nitric Oxide in the Diagnosis of Asthma in Adults

NeuroQuantology ◽

10.14704/nq.2021.19.8.nq21122 ◽

2021 ◽

Vol 19 (8) ◽

pp. 119-124

Author(s):

Hayder Abdul-Amir Makki Al-Hindy ◽

Ali Jihad Hemid Al-Athari ◽

Mazin J. Mousa ◽

Safa Jihad Hameed ◽

Suhad Hafidh Obeed

Keyword(s):

Nitric Oxide ◽

Sensitivity And Specificity ◽

Bronchial Asthma ◽

High Sensitivity ◽

Exhaled Nitric Oxide ◽

Fractional Exhaled Nitric Oxide ◽

Asthmatic Patients ◽

Significant Difference ◽

Asthma Patients ◽

Hs Crp

Background: Bronchial asthma (BrA), recognized lately as an umbrella, covers various subtypes rather than only one disease. Asthma is a chronic inflammation of the airways, in which cytokines could play a crucial role in its pathogenesis. Hence, labors to progress noninvasive markers for asthma had centered through this era. Presently, the fractional exhaled nitric oxide (FeNO), serum C-reactive protein (CRP), and interleukin levels are emerging analytical biomarkers in this field. FeNO is a noninvasive and practical tool even in mild asthma. This study aimed to evaluate the utility of serum IL-1β and CRP together with fractional exhaled nitric oxide in the diagnosis of adult bronchial asthma. Method: The study was a case control, including 150-patients and 100-healthy controls. FeNO tests, measurements of plasma levels IL-1β and HS-CRP had undertaken for all the participants. The statistical data had examined by SPSS (V/27) for Windows. Descriptive data of the variables had compatibly used. A significance lower than or identical to 0.05 had intended. ROC curve examination of FeNO tests, IL-1β, and HS-CRP, to predict asthma from healthy control had applied. Results: there was a significant difference in the FeNo test, HS-CRP levels, and BMI, while no significant difference in all other variables between the groups. The FeNo results correlate positively, though not significantly, with the levels of IL-1β in asthmatic patients (> 0.05). There was a nonsignificant negative correlation between the FeNo results with the level of HSCRP. The accuracy, sensitivity, and specificity of the IL-1β to distinguish asthma were 68.6% and 58% at 95% CI [0.41-0.745], respectively, which was not significant (p>0.05). However, ROC analysis of HS-CRP revealed predictability for asthma patients (p-0.000), with higher accuracy, sensitivity, and specificity: 89.9%, and 68.1% at 95% CI [0.820-0.979], respectively. The FeNo tests revealed highly significant (0.000), high sensitivity, and specific (91% for both) with high 95% CI [0.938-1.000] predictability for asthma. Conclusion: The utility of circulating HS-CRP is more valuable than IL-1β when combined with fractional exhaled nitric oxide in the diagnosis of asthma. Novel biomarkers could improve the precision of this field.

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