Home-Based FeNO Monitoring with the Vivatmome Device Reveals Type2 Inflammatory Patterns of Patients with Asthma at Different Treatment Steps: The FeNO@Home Study.

Association between allergic sensitization and exhaled nitric oxide in children in the School Inner-City Asthma Study

Determinants of asthma control and exacerbations in moderate to severe asthma

<b>Introduction:</b> Asthmatics with BHR to mannitol demonstrate clinical benefit with regular ICS. It has been demonstrated FeNO should be &gt;47ppb for clinical benefits to ICS. However, it has been observed that many with BHR to mannitol have ‘normal’ (0-24ppb) or ‘borderline’ (25-47ppb) FeNO levels, suggesting no benefit with ICS. <b>Aim:</b> To determine if a clinical benefit is observed with ICS in uncontrolled asthmatics with BHR to mannitol that have FeNO levels ≤47ppb. <b>Methods:</b> Adult asthmatics (n=20) who were referred to a pulmonary function laboratory for an assessment of BHR to inhaled mannitol also performed FeNO and the Asthma Control Questionnaire (ACQ). All participants entered the study with an ACQ score &gt;0.75, indicating uncontrolled asthma. Following regular ICS for 6 weeks, FeNO and ACQ scores were reassessed. <b>Results:</b> Patients (n=20, median age 36yrs (range:18-71), 7F;13M) had moderate BHR to mannitol (GeoMean PD₁₅ 81mg, 95% CI 52-126), mean FeNO of 32ppb and an ACQ score of 1.75. The majority (85%) had FeNO &lt;47ppb (8 normal; 9 borderline). ICS for 6 weeks afforded a clinically significant decrease in ACQ score to 0.86 (Δ0.89, p&lt;0.001), associated with a reduction in mean FeNO to 18 ppb (p=0.007). Clinical benefit was also seen when the normal/borderline (&lt;47ppb) group were analysed separately with a decrease in ACQ score to 0.95 (Δ0.81, p&lt;0.001). <b>Conclusion:</b> Clinically significant benefit to ICS was observed in patients with uncontrolled asthma and BHR to mannitol with borderline to normal FeNO levels. This suggests there is a low FeNO phenotype in asthma that is ICS sensitive.

Combining low-frequency oscillometry and spirometry measurements in relation to asthma control and exacerbations in moderate-to-severe asthma

Background: Asthma is a chronic inflammatory airway disease requiring regular monitoring to prevent exacerbation. Conventional clinical assessments may not fully capture airway inflammation, highlighting a need for reliable biomarkers. Fractional exhaled nitric oxide (FeNO) is a non-invasive marker reflecting eosinophilic airway inflammation and may improve asthma control evaluation. Objective: This study aimed to assess asthma control levels in follow-up patients by measuring FeNO and to evaluate the correlation between FeNO values and asthma control status classified according to Global Initiative for Asthma (GINA) guidelines. Methods: A descriptive observational study was conducted on 100 adult asthma patients aged 18–60 years attending follow-up at a tertiary care center. Patients with recent respiratory infections or corticosteroid use were excluded. FeNO levels were measured using a standardized electrochemical analyzer following ATS guidelines. Asthma control was classified per GINA 2022 criteria. Data were analyzed using SPSS version 24.0 with ANOVA to compare mean FeNO across control groups. Ethical approval was obtained, and the study adhered to the Declaration of Helsinki. Results: The mean age was 35.4 ± 10.2 years; 58% were female. Asthma control distribution was 40% controlled, 35% partially controlled, and 25% uncontrolled. Mean FeNO significantly increased with worsening control: 15.2 ± 5.3 ppb (controlled), 34.8 ± 8.7 ppb (partially controlled), and 51.3 ± 12.1 ppb (uncontrolled) (p &lt; 0.001). Higher FeNO levels were strongly associated with poorer asthma control. Conclusion: FeNO measurement effectively distinguishes asthma control levels in follow-up patients, offering a valuable tool for detecting airway inflammation and guiding treatment adjustments. Incorporation of FeNO into routine asthma management can enhance individualized care and improve clinical outcomes.

Exhaled nitric oxide measurements: Correction equation to compare hand-held device to stationary analyzer

Background FeNO has been used as a marker for Th2-mediated airway inflammation in asthma. There is evidence which recommends the use of this biomarker in asthma management. Little is known about whether the FeNO test alone or in combination with the ACT score can reflect asthma control in Vietnamese patients. Materials and Methods A cross-sectional study was conducted in asthmatic patients (≥18 years old) recruited at the University Medical Center, Ho Chi Minh City, Vietnam from March 2016 to March 2017. Asthma control levels were assessed following the GINA 2017 guidelines, and FeNO was measured by a Niox Mino device. FeNO cut-offs predicting asthma control status were determined using the ROC curve analysis. The combination of FeNO and ACT was investigated in detecting well-controlled and uncontrolled asthma. The results of the study are as follows: 278 patients with 68% females, mean age of 44 years, and mean asthma duration of 10 years were analyzed. All patients were treated following step 2 to 4 of GINA guidelines. Mean (SD) FeNO was 30.6 (24) ppb. Patients with uncontrolled (16%), partly controlled (29%), and well-controlled asthma (55%) had a median (IQR) FeNO of 50.0 (74), 25.0 (23), and 21.0 (22.3) ppb, respectively, and the mean of FeNO in the uncontrolled group was significantly higher than that in other groups (p < 0.001). The area under the ROC curve (AUC) for FeNO detecting uncontrolled asthma was 0.730 with an optimal cut-off point of FeNO > 50 ppb, and this AUC increased to 0.89 when combining FeNO and ACT. The AUC for FeNO detecting well-controlled asthma was 0.601 with an optimal cut-off point of FeNO <25 ppb and this AUC increased to 0.78 if combining FeNO and ACT. Conclusions FeNO can predict asthma control status with an estimated cut-off point of <25 ppb for well-controlled and >50 ppb for uncontrolled asthma. The combination of FeNO and ACT provides better information regarding asthma control than FeNO alone, and this combination is useful to predict asthma control statuses in asthmatic patients in Viet Nam.

Monitoring during treatment of asthma is usually done by various clinical tools, spirometry, sputum eosinophils and fractional exhaled nitric oxide. Fractional exhaled nitric oxide is a simple and noninvasive tool and has a good agreement with asthma control test score. This study aims to correlate fractional exhaled nitric oxide with asthma control test score. This cross-sectional study was conducted at National Academy of Medical Sciences, Bir hospital, Chest unit, Department of Medicine, over a duration of six months. Patients aged more than 18 years with bronchial asthma diagnosed at least three months prior were included into the study. Those with recent severe exacerbations, known other chronic respiratory disease and smokers were excluded. Asthma control test score was obtained at baseline. All included patients underwent fractional exhaled nitric oxide measurement followed by measurement of Forced vital capacity(FVC) Forced expiratory volume in one second (FEV1) and FEV1/FVC ratio. Forty patients with a mean age of 40.5±11.1 years were included in the study. Majority were females (65%) and the median duration of symptoms was 24 months (Interquartile range= 18-60). Mean fractional exhaled nitric oxide level was 27.8 (±16.0) parts per billion (ppb) and asthma control test score was 19.3 (±4.7). Mean fractional exhaled nitric oxide levels were significantly different across different severity (well controlled, partially controlled and poorly controlled) of asthma (p=0.013). The mean fractional exhaled nitric oxide values and total asthma control test score shows statistically significant negative correlation (Pearson correlation coefficient (r) = -0.462, p=0.003). Asthma control test and FeNO values guided the change of inhaled steroid dose in 17 of the 40 patients. Fractional exhaled nitric oxide can be used when available, along with asthma control test for monitoring control and adjusting the inhaled steroid dose in asthma.

Fractional exhaled nitric oxide (FeNO) is a noninvasive marker of inflammation, used for monitoring asthma. The aim of this study was to compare FeNO, asthma control test (ACT), and lung function test (spirometry) in children aged 8-15 years. This observational, cross-sectional study was performed on76 asthmatic children (age, 8-15 years), who were referred to the Department of Immunology and Allergy, Children's Medical Center, Tehran, Iran during 2012-2013. Patients were matched for sex and age. The recruited patients were selected via consecutive sampling. FeNO was measured with a portable electrochemical analyzer and forced spirometry was performed according to the American Thoracic Society (ATS) guidelines. The ACT questionnaire was used and completed for all the patients.The mean FeNO was 28.5±29.1 ppb, and the mean ACT score was 19.8±3.6. FeNO was significantly correlated with forced expiratory volume (FEV1) (r, 0.232; p=0.049) or 25-75% maximum expiratory flow (MEF 25-75) (r, -0.304; p=0.009). FeNO showed no significant correlation with ACT score or FEV1/forced vital capacity (FVC) (p>0.05). Additionally, there was no significant correlation between FeNO and changes in FEV1 and MEF 25-75% before and after the administration of bronchodilators (p>0.05). To improve asthma control, childhood ACT, FeNO, and spirometric tests can be used as complementary tools in clinical practice to detect children with poorly controlled asthma.

BackgroundAlthough fractional exhaled nitric oxide (FeNO) is a reliable and easily applied marker of airway inflammation in asthma, the relationship between FeNO and indicators of asthma control [Asthma Control Test (ACT) score] and/or severity (spirometry parameters) remains unclear. This study aims to determine possible correlations between FeNO and ACT score; and between FeNO and spirometry parameters.MethodsA cross-sectional study with convenience sampling was conducted among ambulatory patients in the Asthma & COPD clinic at the University Medical Center, Ho Chi Minh City from March 2016 to March 2017. Using measurement of FeNO, the ACT questionnaire and a spirometry test, correlations were determined between FeNO and the ACT score and spirometry parameters.ResultsFour hundred and ten asthmatic patients (mean age 42 years; 65% female) were included and analyzed; their mean time since onset of asthma was 9.5 years. All patients were treated following step 2 to 4 of GINA guidelines. Mean (SD) FeNO was 29.5 (24.4) parts per billion (ppb) and mean (SD) ACT score was 20.5 (40). A significant difference in FeNO values was found among the three groups with different asthma control levels categorized according to the ACT score (P=0.001) but was not found among the three groups with different asthma treatment levels (P=0.425). FeNO was significantly inversely correlated with the ACT score (Spearman’s r =−0.224, P<0.001) and with spirometry parameters indicate airway obstruction such as predicted FEV1, FEV1/FVC, predicted PEF and predicted FEF25–75% with Spearman’s r were −0.187; −0.143; −0.091 and −0.195, respectively (all P<0.05), whereas no correlation between FeNO and FVC—an indicator of airway restriction—was found.ConclusionsIn these asthmatic patients in Vietnam, an inverse correlation was found between FeNO and the ACT score and between FeNO and spirometry indicators of airway obstruction. Therefore, FeNO may be a useful tool in asthma management.

Background: FENO is assessment of airway eosinophilic inflammation.AIM: To predict postoperative respiratory complications in a patient of cardiac surgery (CABG)METHOD: All patients underwent FENO, COPD6 before surgery. Patients characteristics like age,sex, BMI,smoking history,Left ventricle ejection fraction ,Pulmonary artery wedge pressures(PAWP) were recorded.Monitoring of ECG,SpO2,invasive arterial line, anesthesia protocols, ventilator protocols,peroperative, post operative monitoring,extubation protocols and post operative ICU care were closely monitored. Post operative complications were recorded.RESULT: Total 211 patients had undergone cardiac surgery from 16/08/18 to 05/02/20 .77 patients gave consent for FENO assessment and were included in the study. Male to female ratio was 3:1. Smokers were 22% and 78% were non smokers. Average age was 61.Mean post operative ICU stay was 3.38 days.Out of 77 patients who had undergone preoperative FENO assessment,31% had increased level of FENO and 69% were having normal FENO.In high FENO group,mean FENO was 38.64,mean PAWP before and after surgery is 33.6/15 and 37.4/16.4.Mean ICU stay was 3.4.In normal FENO group mean FENO was 10.3.PAWP before and after was 32.3/14 and 37.9/16.4.Mean ICU stay was 3.4 days.Only 5 patients experienced respiratory complications.3 had raised FENO levels in which one patient died.As our cardiac unit has minimal post operative complications,therefore, we found that that there was no requirment of FENO at our cardiac centre.Conclusion: FENO cannot be used as a predictor to asses post operative respiratory complications in a patient undergoing CABG.

Background: Essential oils are volatile compounds of plant origin increasingly used by allergic and/or asthmatic subjects to purify indoor air. The active compounds of essential oils belong to terpenes, the most widespread biogenic volatile organic compounds (VOC). Although there is substantial literature showing associations between exposure to chemical VOCs and asthmatic symptoms and impaired respiratory function, the impact of essential oils in patients with asthma has never been studied. Objectives: To evaluate the safety of a purifying air spray containing 41 essential oils (PPAS) in patients with mild or moderate allergic asthma. Methods: This was a prospective open study in which 25 mild (19) and moderate (6) asthmatics were exposed to PPAS, one spray twice a day at 8 am and 8 pm in two different corners of a given subjects bedroom for 4 weeks. Before and after 4 weeks of exposure, fractional exhaled nitric oxide (FeNO), lung function and methacholine challenge (PD20) were performed and asthma control was assessed by the 5 questions of the Asthma Control Test (ACT). The spray was weighed after the 4-week exposure to assess compliance. Results: FeNO was the primary endpoint and was thus analyzed in all (N = 25) subjects irrespective of the level of airflow obstruction. The results apply to all (N = 25) subjects in which FeNO could be measured at D1 and D30 (17 subjects). Mean (SD) FeNO amounted to 37.4 (16.6) and to 33.1 (18.7) ppm before and after PPAS exposure, respectively (p = 0.09). No significant change in lung function and methacholine responsiveness was noted after PPAS exposure, the mean PD20 amounting to 1179 (1124.42) μg (range 100–3200) before and to 1226 (1189.8) μg (p = 0.06) after. The mean ACT before and after PPAS exposure amounted to 20.9 (4.2) and 21 (5.15), respectively (p = 0.80). The mean weight of the PPAS bottles was 211.4 g (DS:0) before the first use and 171.41 g (DS: 29.8) at the end of the study. The average amount of PPAS used was 40.0 g (29.8). In the subgroup of subjects who used the highest quantities of essential oils (>40 g), as assessed by the mean weight of the bottle at the end of the study, FeNO after 30 days of exposure decreased more than in the entire group: 7.9 ppm vs 4.2 ppm (p = 0.07). Conclusion: No difference was noted on airway inflammation, lung function or asthma control in mild and moderate allergic asthmatics after exposure twice a day for one month, to a spray containing a mixture of 41 essential oils.

Fractional exhaled nitric oxide as a potential biomarker for radiation pneumonitis in patients with non-small cell lung cancer: A pilot study

RATIONALE: We have reported that diurnal variation of fractional exhaled nitric oxide (FeNO) could be useful in the assessment of asthma control and future risks of asthma exacerbation (Saito J, ERJ 2014). However, it is unclear how asthma treatment influences diurnal variation of FeNO. OBJECTIVES: To compare diurnal variation of FeNO before and after intensive asthma treatment. METHODS: Sixteen healthy subjects and ten uncontrolled or partially controlled asthmatic subjects were enrolled in the study. In asthmatic subjects, FeNO and peak expiratory flow (PEF) were measured twice daily using portable monitors (NObreath® and PIKO®) for 1 week before starting intensive treatment and for 2 weeks thereafter. In healthy subjects, FeNO and PEF were also measured for 2 weeks as a normal control. Asthma control questionnaire (ACQ) and spirometry before and after treatment were also performed to assess the treatment effect. RESULTS: Diurnal FeNO variation and mean FeNO levels in asthmatic subjects were significantly greater than in healthy subjects, whereas mean PEF levels, but not diurnal PEF variation, were significantly lower compered to healthy subjects. For the FeNO and PEF levels before and after treatment, only diurnal FeNO variation in the 2nd week after treatment decreased significantly than before treatment. Other parameters including mean FeNO levels, mean PEF levels and diurnal PEF variation showed no significant change after 2 weeks of treatment, although 9 of 10 asthmatic subjects achieved good control by ACQ scores and spirometry. CONCLUSIONS: These results suggest thatdiurnal FeNO variation is useful for predicting short-term treatment effect in asthmatic patients.

Background The fractional exhaled nitric oxide (FENO) test is useful in asthma patients. However, a few studies on its usefulness in chronic obstructive pulmonary disease (COPD) patients have been reported. We analyzed the FENO level distribution and clinical characteristics according to the FENO level in COPD patients.Methods From December 2014 to June 2019, COPD patients who underwent pulmonary function and FENO tests at Chonnam National University Hospital were retrospectively evaluated for FENO, comorbidities, asthma history, blood eosinophil, and pulmonary function test. The high FENO group was defined as those with FENO level>25 parts per billion (ppb).Results A total of 849 COPD patients (mean age, 70.3±9.4 years) were included. The mean forced expiratory volume at 1 second was 66.5±21.7% and the mean FENO level was 24.3±20.5 ppb. Patients with FENO ≤25 ppb were 572 (67.4%) and those with FENO >25 ppb were 277 (32.6%). Blood eosinophil percentage was significantly higher (4.2±4.8 vs. 2.7±2.5, p<0.001) in patients with the high FENO group than the low FENO group. The high FENO group revealed a significantly higher frequency of patients with blood eosinophil percentage >3% (46.9% vs. 34.8%, p=0.001) and asthma history (25.6% vs. 8.6%, p<0.001) than the lower FENO group. Asthma history, blood eosinophil percentage >3%, and positive bronchodilator response (BDR) were independent risk factors for the high FENO level (adjusted odds ratio [aOR], 3.85; p<0.001; aOR, 1.46; p=0.017; and aOR, 1.57, p=0.034, respectively) in the multivariable analysis.Conclusion The FENO level distribution varied in COPD patients and the mean FENO value was slightly elevated. Asthma history, eosinophil percent, and positive BDR were independent risk factors for the high FENO level.