Exhaled nitric oxide in patients with chronic obstructive pulmonary disease: a systematic review and meta-analysis

Abstract

BackgroundFractional exhaled nitric oxide (FENO) is a useful and noninvasive biomarker for eosinophilic airway inflammation, particularly in asthma. However, its utility in chronic obstructive pulmonary disease (COPD) remains controversial. In this study, we performed a systematic review and meta-analysis to evaluate FENO levels in COPD.MethodsA search of PubMed, Embase, Cochrane Library, and clinical trial registry was conducted from inception to January 2018. Studies were included if they reported FENO levels in patients with COPD and healthy controls. We then extracted relevant information and analyzed data. Standard mean difference (SMD) with 95% confidence interval (CI) was applied in this meta-analysis.ResultsA total of 2,073 studies were reviewed for eligibility, with 24 studies pooled for analysis. The FENO levels in patients with COPD were elevated mildly compared with healthy controls (SMD 1.28, 95% CI 0.60–1.96). A similar result was also observed in stable COPD, with an SMD of 1.21 (95% CI 0.47–1.96). On the other hand, we found no association between FENO levels and exacerbated COPD. Additionally, for patients with COPD, ex-smokers had higher levels of FENO than current smokers (SMD 2.05, 95% CI 1.13–2.97).ConclusionOur studies demonstrated a mild elevation of FENO in COPD, and the association between exacerbated COPD and FENO levels needs to be further explored. The potential mechanism is still unknown and conflicting.

Clinical Features of Chronic Obstructive Pulmonary Disease with High Fractional Exhaled Nitric Oxide

“…However, the median FENO level (19.0 [13.0–29.0]) in our study was somewhat higher than the median level (16.0) in the ATS/ERS guidelines [ 8 ] or that of the report of Jo et al (median, 13.0) [ 17 ]. These results are consistent with the previous findings that the FENO values of COPD patients were normal or mild elevated [ 18 , 19 ].…”

“…Kim et al 16 reported that mean FENO level in non-atopic males was 33.9±14.3, 37.3±12.1 in atopic males, 24.1±10.6 in non-atopic females, and 28.6±17.7 in atopic females. Jo et al 17 reported that mean and median FENO levels in healthy populations were 14.4±9.0, 13.0 (8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19). In two previous studies conducted in Korea, there was a large difference in normal FENO level.…”

Organic-Inorganic Hybrid Materials for Room Temperature Light-Activated Sub-ppm NO Detection

“…DRIFT spectroscopy was performed to investigate the interaction between NO and the surface of the synthesized materials. Sensor measurements demonstrate that hybrid materials are able to detect NO at room temperature in the concentration range of 0.25-4.0 ppm with the detection limit of 69-88 ppb.Nanomaterials 2020, 10, 70 2 of 22 in noninvasive diagnosis of respiratory diseases [7][8][9]. In this case, the limitation of the quantitative determination of NO in exhaled air is due to the low level of its concentration (20-200 ppb) among a wide range of interfering gases [10].Direct determination of nitrogen monoxide in the gas phase is possible using conductometric gas sensors based on various semiconductor metal oxides [7,[10][11][12][13][14][15][16][17][18][19][20][21][22].…”

“…Nanomaterials 2020, 10, 70 2 of 22 in noninvasive diagnosis of respiratory diseases [7][8][9]. In this case, the limitation of the quantitative determination of NO in exhaled air is due to the low level of its concentration (20-200 ppb) among a wide range of interfering gases [10].…”

ГЕМОДИНАМІЧНА ФУНКЦІЯ ЛЕГЕНЬ ТА НАСИЧЕННЯ КРОВІ КИСНЕМ ПРИ ІНТРАБРОНхІАЛЬНОМУ ЗАСТОСУВАННІ ІНФУЗІЙ МОНООКСИДУ АЗОТУ У ХВОРИх НА ХРОНІЧНИЙ БРОНхІТ

“…Встановлено, що у пацієнтів зі стабільним ХОЗЛ у повітрі, що видихається, також збільшується вміст NO у порівнянні зі здоровими суб'єктами [8][9][10]. Потенційний механізм його зростання у пацієнтів з ХОЗЛ досі невідомий і суперечливий [11].…”