Association Between FeNO, Total Blood IgE, Peripheral Blood Eosinophil and Inflammatory Cytokines in Partly Controlled Asthma

Associations between the Dietary Inflammatory Index and fractional exhaled nitric oxide among United States adults: A cross-sectional study

BACKGROUND

Fractional exhaled nitric oxide (FeNo) is a convenient and noninvasive test that measures the concentration of nitric oxide in exhalation as a surrogate biomarker of airway inflammation. This cross-sectional study aimed to determine the associations between Dietary Inflammatory Index (DII) and FeNo in US adults.

METHODS

Adults participating in the 2007-2012 cycles of the US National Health and Nutrition Examination Survey with complete information and available measurement data of DII and FeNo were included. Associations between DII and FeNo were assessed using univariable and multivariable logistic regression models, restricted cubic spline analysis, stratified analysis, and sensitivity analysis.

RESULTS

A total of 7677 participants (mean age 45.68 years, 53.03% men) with a mean DII of 1.28 and FeNo of 17.33 ppb were included. The multivariable-adjusted linear regression analysis showed that a one-unit increase in DII was associated with a 0.283-ppb reduction in FeNo level. The beta and 95% CI for the second, third, and fourth DII quartile groups were -1.19 (-2.04 to -0.35), -1.07 (-2.26 to 0.12), and -1.60 (-2.85 to -0.36), respectively (P for trend = 0.04), with the lowest quartile group as the reference. The restricted cubic spline curve showed an inversely linear relationship between DII and FeNo. The study result is robust and did not appear to be affected by the participant's age, sex, race, body mass index, physical activity, diabetes status, or white blood cell or eosinophil counts.

CONCLUSION

A proinflammatory diet, as indicated by a higher DII, is cross-sectionally associated with lower FeNo levels in US adults.

Relationship between fraction of exhaled nitric oxide and peripheral eosinophilia in asthma

BACKGROUND

Achieving disease control is the goal of asthma management. Serum or sputum eosinophil counts have been known traditional means of assessing eosinophilic airway inflammation in asthma, which is vital in predicting response to corticosteroid therapy which ultimately promotes control of the disease. Evidence suggests that fraction of exhaled nitric oxide (FeNO) may be a more useful non-invasive surrogate biomarker for the assessment of eosinophilic airway inflammation and could help with the timely adjustment of inhaled corticosteroid therapy in the uncontrolled asthma patient. The relationship between FeNO and other markers of airway inflammation has been variable in literature, with limited data in sub-Saharan Africa where FeNO testing is very sparse. We sought to define the relationship between FeNO levels, serum eosinophil counts, spirometry measures and symptom control among asthma patients.

MATERIALS AND METHODS

The study was conducted at the Asthma Clinic of a large tertiary hospital. This study included 82 patients with physician-diagnosed asthma being regularly managed at the clinic. All participants were taken through the asthma control test (ACT), had FeNO and spirometry measurements taken according to the American Thoracic Society (ATS) guidelines. Blood samples were obtained from all participants for serum eosinophil counts. Correlation coefficient was used to ascertain the relationship between FeNO levels and serum eosinophil counts, ACT scores, and spirometry measurements. Logistic regression was used to examine the association between high FeNO and abnormal FEV1 percentage predicted (<80%) with adjustments for age, sex, and BMI.

RESULTS

A total of 82 patients with asthma were included in the study, with higher prevalence of females (72%). Majority (40.2%) of the patients were found in the 60 and above age category. The median FeNO level and ACT score was 42.00 (26.00-52.50) parts per billion (ppb) and 20.0 (18-23) respectively. The median serum eosinophil counts was 0.25(0.90-0.38) × 109/L. The median FeNO levels were significantly higher in patients with partly and very poorly controlled asthma than in the well-controlled group (p < 0.001). A total of 47(57%) of the patients were classified as having well controlled asthma and 35 (42%) uncontrolled. FeNO correlated with serum eosinophil counts (r = 0.450, p < 0.001), ACT (r = -0.648, p < 0.001), and FEV1 percentage predicted (r = -0.353, p = 0.001). High FeNO (>50 ppb) was associated with an over fivefold increased risk of having an abnormal FEV1 percentage predicted.

CONCLUSION

FeNO levels significantly correlated with the ACT scores, serum eosinophil counts and FEV1% predicted among the asthma patients who were on inhaled corticosteroid therapy. High FeNO was significantly associated with abnormal FEV1 percentage predicted. We suggest that the point of care assessment of FeNO is a reliable marker of eosinophilic inflammation in our cohort of patients and together with 'ACT scores' in our asthma clinics could increase asthma control rates.

The Association of Nasal and Blood Eosinophils with Serum IgE Level in Allergic Rhinitis and Asthma: A Case-Control Study

Background and Aims

Allergic rhinitis and asthma are two common respiratory diseases with allergic etiology in the world's population. Eosinophils and serum IgE levels have been known as inflammatory allergy markers for many years. This study aimed to evaluate the correlation of nasal and blood eosinophils with serum IgE levels in allergic rhinitis and asthma patients.

Methods

This prospective study was done on patients (n = 78) diagnosed with asthma (n = 20), allergic rhinitis (n = 49), and chronic rhinosinusitis with nasal polyposis (CRSwNP) (n = 9) at our hospital in Ahvaz City, Iran. The age of participants in our study ranged from 3 to 73 years, and all of them were subjected to a complete blood count (CBC) test, nasal smear, and determination of serum IgE levels after their consent.

Results

There was no correlation between serum IgE level and nasal eosinophil count (p = 0.728) or between serum IgE level and blood eosinophil count (p = 0.657); however, a positive correlation was detected between blood and nasal eosinophil levels (p = 0.003).

Conclusion

There is no significant relationship between serum IgE level and eosinophil count in the blood and nasal secretions. Serum IgE level and blood or nasal eosinophil count are both useful biomarkers for monitoring allergic rhinitis and asthma individually, but no diagnostic conclusion can be drawn from their correlation.

Type 2 inflammation in COPD: is it just asthma?

COPD is a heterogeneous condition, with tobacco smoking being the main environmental risk factor. The presence of type 2 (T2) inflammation is a well-recognised feature of asthma; however, it is now apparent that a subset of COPD patients also displays evidence of T2 inflammation with respect to elevated eosinophil counts and altered gene and protein expression of several T2 inflammatory mediators. T2 inflammatory mediators represent an attractive therapeutic target in both COPD and asthma; however, the efficacy of pharmaceutical interventions varies between diseases. Furthermore, the nature of some shared clinical features also differs. We provide a narrative review of differences in the nature of T2 inflammation between COPD and asthma, which may partly explain phenotypic differences between diseases. We focus on evidence from studies of pulmonary histopathology, sputum and epithelial gene and protein expression, and response to pharmacological interventions targeted at T2 inflammation.

Prognostic value of serum total IgE and FeNO levels in children with atopic constitution bronchiolitis

Bronchiolitis is a significant factor contributing to bronchial asthma in infants and young children. After treatment, recurrent wheezing symptoms often occur, especially in children with atopic constitution, who tend to have more severe conditions and poorer prognosis. Therefore, exploring the prognostic value of total serum immunoglobulin E (tIgE) and fractional exhaled nitric oxide (FeNO) levels in children with atopic constitution who suffer from bronchiolitis is of great significance. A total of 260 children with bronchiolitis admitted to our hospital from October 2020 to June 2022 were regarded as the research subjects with prospective study, according to whether the children had atopic constitution, they were grouped into non atopic constitution group (n = 156) and atopic constitution group (n = 104); after 6 months of treatment, children with atopic constitution were grouped into a good prognosis group (n = 58) and a poor prognosis group (n = 46) based on their prognosis; in addition, 260 healthy children who underwent physical examination and had clinical data consistent with those of children with bronchiolitis were regarded as the reference group. The serum tIgE and FeNO levels of each group were compared; multivariate Logistic regression was applied to analyze the prognostic factors of children with atopic constitution bronchiolitis; ROC curve was applied to analyze the predictive value of tIgE and FeNO levels after treatment for the prognosis of children with atopic constitution bronchiolitis. The tIgE levels in the control group, non-atopic group, and atopic group [(123.54 ± 29.62) IU/mL, (245.71 ± 30.59) IU/mL, (316.46 ± 31.78) IU/mL, respectively] increased sequentially, with statistically significant differences (F = 1766.954, P = 0.000). The FeNO levels in the control group, non-atopic group, and atopic group [(8.36 ± 3.57) ppb, (15.28 ± 3.69) ppb, (19.84 ± 3.58) ppb, respectively] also increased sequentially, with statistically significant differences (F = 765.622, P = 0.000). The tIgE, FeNO, proportion of patients with asthma family history, and proportion of patients with allergic family history in the poor prognosis group were obviously higher than those in the good prognosis group (P < 0.05). Multivariate Logistic regression analysis showed that family history of asthma, family history of allergies, tIgE, and FeNO were influencing factors for the prognosis of children with atopic bronchiolitis (P < 0.05). The AUC of the combination of tIgE and FeNO in predicting the prognosis of children with atopic constitutional bronchiolitis was 0.910, with a sensitivity of 78.26% and a specificity of 93.10%, which was superior to the independent prediction of tIgE and FeNO (Zcombined detection-tIgE = 2.442, Zcombined detection-FeNO = 3.080, P = 0.015, 0.002). The levels of tIgE and FeNO in children with atopic constitution bronchiolitis are obviously increased, and the combination of the two has high predictive value for the prognosis of atopic constitution bronchiolitis.

Exhaled nitric oxide is only an asthma-relevant biomarker among children with allergic sensitization

BACKGROUND

Fraction of exhaled nitric oxide (FeNO) is used for diagnosing and monitoring asthma in children, but the influence of allergic sensitization is still poorly understood. Here, we investigate how asthma and allergic sensitization influence FeNO levels during childhood.

METHODS

We investigated the associations between asthma, aeroallergen sensitization, and FeNO measured from age 5-18 years in the COPSAC2000 birth cohort of 411 children using repeated measurement mixed models adjusted for gestational age, sex, concurrent airway infection, inhaled corticosteroids, and tobacco exposure. Replication was sought in the similarly designed COPSAC2010 cohort of 700 children.

RESULTS

In the COPSAC2000 cohort, 133 had asthma between age 5 and 18 years, and in the COPSAC2010 cohort, 112 had asthma between age 5 and 10 years. In the COPSAC2000 cohort, asthma and aeroallergen sensitization were both associated with higher FeNO from age 5 to 18 years: adjusted geometric mean ratio (aGMR), 1.22 (1.08-1.35), p < .01, and 1.41 (1.21-1.65), p < 0.001, respectively. However, asthma was associated with increased FeNO among children with aeroallergen sensitization: 1.44 (1.23-1.69), p < .0001, whereas asthma was associated with decreased FeNO among nonsensitized children: 0.80 (0.65-0.99), p = .05 (p-interaction<.0001 for asthma x sensitization). Replication in the COPSAC2010 cohort showed similar results (p-interaction <.01). Further, blood eosinophil count, total-IgE, bronchodilator response, and bronchial hyperreactivity were all associated with increased FeNO among children sensitized to aeroallergens, but not among nonsensitized children.

CONCLUSION

Fraction of exhaled nitric oxide is elevated through childhood in children with asthma and is correlated with asthma-associated traits depending on the presence of aeroallergen sensitization. These findings indicate that FeNO is only a valid asthma biomarker in children with concurrent aeroallergen sensitization, which is important for guideline recommendations on the clinical use of FeNO.

Obese Asthma Phenotype Is Associated with hsa-miR-26a-1-3p and hsa-miR-376a-3p Modulating the IGF Axis

Clarifying inflammatory processes and categorising asthma into phenotypes and endotypes improves asthma management. Obesity worsens severe asthma and reduces quality of life, although its specific molecular impact remains unclear. We previously demonstrated that hsa-miR-26a-1-3p and hsa-miR-376a-3p, biomarkers related to an inflammatory profile, discriminate eosinophilic from non-eosinophilic asthmatics. We aimed to study hsa-miR-26a-1-3p, hsa-miR-376a-3p, and their target genes in asthmatic subjects with or without obesity to find biomarkers and comprehend obese asthma mechanisms. Lung tissue samples were obtained from asthmatic patients (n = 16) and healthy subjects (n = 20). We measured miRNA expression using RT-qPCR and protein levels (IGF axis) by ELISA in confirmation samples from eosinophilic (n = 38) and non-eosinophilic (n = 39) obese (n = 26) and non-obese (n = 51) asthma patients. Asthmatic lungs showed higher hsa-miR-26a-1-3p and hsa-miR-376a-3p expression than healthy lungs. A study of seven genes regulated by these miRNAs revealed differential expression of IGFBP3 between asthma patients and healthy individuals. In obese asthma patients, we found higher hsa-miR-26a-1-3p and IGF-1R values and lower values for hsa-miR-376a-3p and IGFBP-3. Hsa-miR-26a-1-3p and IGFBP-3 were directly and inversely correlated with body mass index, respectively. Hsa-miR-26a-1-3p and hsa-miR-376a-3p could be used as biomarkers to phenotype patients with eosinophilic and non-eosinophilic asthma in relation to comorbid obesity.

The Correlation Between Fractional Exhaled Nitric Oxide (FeNO), Blood Eosinophil Count, Immunoglobulin E Levels, and Spirometric Values in Patients With Asthma

BACKGROUND AND OBJECTIVE

In patients with asthma, fractional exhaled nitric oxide (FeNO) is a biomarker for eosinophilic airway inflammation. However, the correlation with the blood eosinophil count, immunoglobulin E (IgE), and spirometric values is not well established. We aimed to investigate the correlation between FeNO, blood eosinophils, IgE, and spirometric values in asthmatic patients.

METHODS

Data were extracted from the electronic medical records of adult asthmatic patients, and included the FeNO, blood eosinophil count, IgE, and spirometric values. The correlation between the markers was investigated using receiver operating characteristics (ROC) and the area under the curve (AUC).

RESULTS

A total of 135 adult patients (30% male) were analyzed. The mean FeNO was 36 ppb and almost half (48%) had a FeNO > 25 ppb. The mean blood eosinophil count was 377 cells/mm³, and 42% had a blood eosinophil count > 300 cells/mm³. There was a significant positive correlation between FeNO and the blood eosinophil count (r = 0.42, sensitivity 63%, specificity 77%, AUC 72%, p < 0.0001) as well as with the IgE (r = 0.35, sensitivity 78%, specificity 44%, AUC 68%, p < 0.0007). There was significant negative correlation between FeNO and FEV1% (r = -0.18, sensitivity 35%, specificity 85%, AUC 67%, p = 0.027).

CONCLUSION

The blood eosinophil count, IgE, and spirometric values were correlated with the severity of the eosinophilic airway inflammation (high FeNO). Asthmatic patients with a higher FeNO level had a higher eosinophil count, higher IgE levels, and lower FEV1 values.

The Role of Nasal Cytology and Serum Atopic Biomarkers in Paediatric Rhinitis

A Nasal Provocation Test allows the differentiation of allergic and non-allergic rhinitis, but it is difficult and expensive. Therefore, nasal cytology is taking hold as an alternative. We carried out a cross-sectional study, including 29 patients with persistent rhinitis according to ARIA definition and negative skin prick tests. Nasal symptoms were scored from 0 to 5 using a visual analogue scale, and patients underwent blood tests to investigate blood cell count (particularly eosinophilia and basophilia), to analyze serum total and specific IgE and eosinophil cationic protein (ECP), and to perform nasal cytology. We performed a univariate logistical analysis to evaluate the association between total serum IgE, serum eosinophilia, basophils, and ECP and the presence of eosinophils in the nasal mucosa, and a multivariate logistic model in order to weight the single variable on the presence of eosinophils to level of the nasal mucosa. A statistically significant association between serum total IgE levels and the severity of nasal eosinophilic inflammation was found (confidence interval C.I. 1.08-4.65, odds ratio OR 2.24, p value 0.03). For this reason, we imagine a therapeutic trial with nasal steroids and oral antihistamines in patients with suspected LAR and increased total IgE levels, reserving nasal cytology and NPT to non-responders to the first-line therapy.

Efficacy of vitamin D supplementation on COPD and asthma control: A systematic review and meta-analysis

Background

The role of vitamin D (VD) in the management of chronic obstructive pulmonary disease (COPD) and asthma remains largely undetermined. In the present meta-analysis, we aimed to comprehensively investigate the efficacy of VD in the treatment of COPD and asthma according to the latest update.

Methods

The PubMed, Embase, and Cochrane Library databases were searched from their inception to June 2, 2022. Randomized controlled trials (RCTs) comparing the efficacy of VD with placebo against COPD or asthma were included.

Results

A total of 11 RCTs consisting of 1183 COPD patients and 19 RCTs consisting of 2025 asthmatic patients were finally included. As for pulmonary function, FEV1/FVC was not changed significantly, while FEV1% was improved in the VD group. In the asthma subgroup, FEV1% was not changed significantly, while FEV1/FVC was improved in the VD group. For the questionnaire and rating scale, the mMRC (modified Medical Research Council) dyspnoea scale score for COPD and ACT (Asthma Control Test) score for asthma were not significantly changed, while the SGRQ (St. George's Respiratory Questionnaire) score for COPD was improved in the VD group. For inflammation indicators, IL-6 and IL-10 were statistically equivalent between the VD and placebo groups, while IgE, IL-5, and IL-10 (baseline VD deficiency subgroup) were improved in the VD group. The exacerbation, length of hospital stays, and mortality were statistically equivalent between the two groups.

Conclusions

VD supplementation improved the indicators of asthma and COPD, especially in pulmonary function, SGRQ scores, IL-5, and IgE.

Registration

The protocol could be found at PROSPERO with the registration number of CRD42020218058.

Predictive characteristics to discriminate the longitudinal outcomes of childhood asthma: a retrospective program-based study

BACKGROUND

Childhood asthma is an inflammatory disease with heterogeneous outcomes. We sought to determine the impact of total IgE, blood eosinophil, allergen sensitization, and inhaled corticosteroid (ICS) on longitudinal outcomes and to identify characteristics for discriminating different outcomes.

METHODS

We conducted a retrospective study in 383 childhood asthma patients and another 313 patients with blood eosinophil data only receiving regular program-based visits from September 1, 2004, to December 31, 2018. Peak expiratory flow (PEF) variability, PEF predicted %, asthma severity, and asthma control at each visit were assessed as clinical outcomes.

RESULTS

Our data show that the percentage of blood eosinophils was significantly associated with increased asthma severity (OR: 1.043, 95% CI: 1.002-1.086, P = 0.0392). Mold sensitization was significantly associated with asthma severity (OR: 2.2485, 95% CI: 1.3253-3.8150, P = 0.0027). Characteristics including sensitization status plus ICS dosage had the best area under the receiver operating characteristic curve (AUC) value for predicting longitudinal PEF predicted % (0.6609), PEF variability (0.6885), asthma severity (0.5918), and asthma control (0.6441), respectively.

CONCLUSIONS

We showed that the risk for adverse clinical outcomes at follow-up differed between serum IgE, blood eosinophil, and allergen sensitization identified at baseline. Sensitization and ICS dosage were predictive characteristics of long-term clinical outcomes.

IMPACT

The unique aspects of the study are its longitudinal assessment of patients receiving guideline-based asthma management program to help characterize the stability of the clinical outcomes over time. Characteristics including allergen sensitization and ICS dosage demonstrated an improved capability for distinguishing between better and worse clinical outcomes. Through longitudinal serial assessment, this study indicates the risk for adverse clinical outcomes differed between children with serum IgE/blood eosinophil/allergen sensitization characterized at baseline.

Application of fractional exhaled nitric oxide and nasal nitric oxide in control evaluation of bronchial asthma and diagnosis of allergic rhinitis in children

OBJECTIVES

To study the association of fractional exhaled nitric oxide (FeNO) and nasal nitric oxide (nNO) with asthma control and their value in the diagnosis of allergic rhinitis in children.

METHODS

A total of 186 children aged 5-12 years, who attended the outpatient service of the Department of Respiration, Shanghai Children's Hospital due to bronchial asthma and/or allergic rhinitis or who underwent physical examination, were enrolled as subjects, with 52 children in the asthma group, 60 children in the asthma+allergic rhinitis group, 36 children in the allergic rhinitis group, and 38 children in the control group. FeNO, nNO, and pulmonary function were compared between groups.

RESULTS

The asthma+allergic rhinitis, asthma, and allergic rhinitis groups had a significantly higher level of FeNO than the control group (P<0.05). The asthma+allergic rhinitis and allergic rhinitis groups had a significantly higher level of nNO than the asthma and control groups (P<0.05). The uncontrolled asthma and partially controlled asthma groups had significantly higher levels of FeNO and nNO than the completely controlled asthma group (P<0.05). The receiver operating characteristic (ROC) curve analysis showed that nNO had an area under the ROC curve of 0.91, with a sensitivity of 80.0% and a specificity of 89.5% in the diagnosis of allergic rhinitis in children with asthma (P<0.05).

CONCLUSIONS

The combined measurement of nNO and FeNO can be used to evaluate the control of asthma, and the measurement of nNO can help with the diagnosis of allergic rhinitis in children with bronchial asthma.

Bronchopulmonary dysplasia as a determinant of respiratory outcomes in adult life

Respiratory disease is unfortunately common in preterm infants with the archetype being bronchopulmonary dysplasia (BPD). BPD affects approximately 50,000 preterm infants in the U.S. annually with substantial morbidity and mortality related to its pathology (alveolar, airway, and pulmonary vasculature maldevelopment). Predicting the likelihood and severity of chronic respiratory disease in these children as they age is difficult and compounded by the lack of consistent phenotyping. Barriers to understanding the actual scope of this problem include few longitudinal studies, information limited by small retrospective studies and the ever-changing landscape of therapies in the NICU that affect long-term respiratory outcomes. Thus, the true burden of adult respiratory disease caused by premature birth is currently unknown. Nevertheless, limited data suggest that a substantial percentage of children with a history of BPD have long-term respiratory symptoms and persistent airflow obstruction associated with altered lung function trajectories into adult life. Small airway disease with variable bronchodilator responsiveness, is the most common manifestation of lung dysfunction in adults with a history of BPD. The etiology of this is unclear however, developmental dysanapsis may underlie the airflow obstruction in some adults with a history of BPD. This type of flow limitation resembles that of aging adults with chronic obstructive lung disease with no history of smoking. It is also unclear whether lung function abnormalities in people with a history of BPD are static or if these individuals with BPD have a more accelerated decline in lung function as they age compared to controls. While some of the more significant mediators of lung function, such as tobacco smoke and respiratory infections have been identified, more work is necessary to identify the best means of preserving lung function for individuals born prematurely throughout their lifespan.

Correlation study of cytokine levels in alveolar lavage fluid with exhaled nitric oxide and lung function in children with bronchial asthma

BACKGROUND

The associations between cytokines in the bronchoalveolar lavage fluid (BALF), lung cytokine expression, fractional exhaled nitric oxide (FeNO) and pulmonary function test results in pediatric asthmatics have not been extensively characterized. This study sought to explore correlations between cytokines BALF, FeNO, and pulmonary function test results.

METHODS

From October 2018 to October 2020, a prospective study was conducted on 42 children with asthma and 17 children with pulmonary foreign bodies that required bronchoscopy. Pulmonary function tests and FeNO tests were performed on all patients. Patients were divided into a high FeNO group or low FeNO group based on their FeNO results. Interleukin (IL)-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in the BALF were measured by enzyme-linked immunosorbent assays. Pearson correlations were used to assess the correlations between the cytokines in BALF, the pulmonary function test results, and the FeNO results. Pearson correlation was used to calculate the correlation coefficient "r" among alveolar lavage fluid cytokines, lung function, and FeNO. Receiver operating characteristic (ROC) curves were used to determine the area under the curve (AUC), sensitivity, and specificity of BALF cytokines for the high and low FeNO groups.

RESULTS

IL-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in BALF were significantly correlated with FeNO, but were not significantly correlated with the pulmonary function test results. Cytokine IL-4, IL-5, IL-6, IL-8, IL-13, and IL-17 in BALF were significantly different in the high FeNO, low FeNO, and control groups (all P<0.05). The AUCs for differentiating between low and high FeNO based on BALF cytokines ranged from 0.72 to 0.95. The sensitivity and specificity for discriminating between low and high FeNO based on IL-5 and IL-13 reached 95.7% and 100%, respectively.

CONCLUSIONS

The cytokine levels of the BALF of children with asthma were significantly elevated, correlated with FeNO, and can be used evaluate airway inflammation in children with asthma.