AIR POLLUTION INFLUENCES ON EXHALED NITRIC OXIDE AMONG PEOPLE WITH TYPE II DIABETES

The association between short-term exposure to ambient air pollution and fractional exhaled nitric oxide level: A systematic review and meta-analysis of panel studies

Several epidemiological studies have evaluated the fractional exhaled nitric oxide (FeNO) of ambient air pollution but the results were controversial. We therefore conducted a systematic review and meta-analysis to investigate the associations between short-term exposure to air pollutants and FeNO level. We searched PubMed and Web of Science and included a total of 27 articles which focused on associations between ambient air pollutants (PM₁₀, PM_2.5, black carbon (BC), nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone (O₃)) exposure and the change of FeNO. Random effect model was used to calculate the percent change of FeNO in association with a 10 or 1 μg/m³ increase in air pollutants exposure concentrations. A 10 μg/m³ increase in short-term PM₁₀, PM_2.5, NO₂, and SO₂ exposure was associated with a 3.20% (95% confidence interval (95%CI): 1.11%, 5.29%), 2.25% (95%CI: 1.51%, 2.99%),4.90% (95%CI: 1.98%, 7.81%), and 8.28% (95%CI: 3.61%, 12.59%) change in FeNO, respectively. A 1 μg/m³ increase in short-term exposure to BC was associated with 3.42% (95%CI: 1.34%, 5.50%) change in FeNO. The association between short-term exposure to O₃ and FeNO level was insignificant (P＞0.05). Future studies are warranted to investigate the effect of multiple pollutants, different sources and composition of air pollutants on airway inflammation.

Meditation and Yoga Practices as Potential Adjunctive Treatment of SARS-CoV-2 Infection and COVID-19: A Brief Overview of Key Subjects

Editor's Note: As an acute condition quickly associated with multiple chronic susceptibilities, COVID-19 has rekindled interest in, and controversy about, the potential role of the host in disease processes. While hundreds of millions of research dollars have been funneled into drug and vaccine solutions that target the external agent, integrative practitioners tuned to enhancing immunity faced a familiar mostly unfunded task. First, go to school on the virus. Then draw from the global array of natural therapies and practices with host-enhancing or anti-viral capabilities to suggest integrative treatment strategies. The near null-set of conventional treatment options propels this investigation. In this paper, researchers from the Massachusetts Institute of Technology, University of California-San Diego, Chopra Library for Integrative Studies, and Harvard University share one such exploration. Their conclusion, that "certain meditation, yoga asana (postures), and pranayama (breathing) practices may possibly be effective adjunctive means of treating and/or preventing SARS-CoV-2 infection" underscores the importance of this rekindling. At JACM, we are pleased to have the opportunity to publish this work. We hope that it might help diminish in medicine and health the polarization that, like so much in the broader culture, seems to be an obstacle to healing. -John Weeks, Editor-in-Chief, JACM.

Ambient air pollution is associated with airway inflammation in older women: a nested cross-sectional analysis

BACKGROUND

Air pollution is a risk factor for chronic obstructive pulmonary disease (COPD). Fraction of exhaled nitric oxide (FeNO) could be a useful biomarker for health effects of air pollutants. However, there were limited data from older populations with higher prevalence of COPD and other inflammatory conditions.

METHODS

We obtained data from the German Study on the influence of Air pollution on Lung function, Inflammation and Ageing. Spirometry and FeNO were measured by standard techniques. Air pollutant exposures were estimated following the European Study of Cohorts for Air Pollution Effects protocols, and ozone (O3) measured at the closest ground level monitoring station. Multiple linear regression models were fitted to FeNO with each pollutant separately and adjusted for potential confounders.

RESULTS

In 236 women (mean age 74.6 years), geometric mean FeNO was 15.2ppb. Almost a third (n=71, 30.1%) of the women had some chronic inflammatory respiratory condition. A higher FeNO concentration was associated with exposures to fine particles (PM2.5), PM2.5absorbance and respirable particles (PM10). There were no significant associations with PMcoarse, NO2, NOx, O3 or length of major roads within a 1 km buffer. Restricting the analysis to participants with a chronic inflammatory respiratory condition, with or without impaired lung function produced similar findings. Adjusting for diabetes did not materially alter the findings. There were no significant interactions between individual pollutants and asthma or current smoking.

CONCLUSIONS

This study adds to the evidence to reduce ambient PM2.5 concentrations as low as possible to protect the health of the general population.

Obesity, sedentary lifestyle, and exhaled nitric oxide in an early adolescent cohort

Fractional exhaled nitric oxide (FeNO) is a marker of airway inflammation that is well-characterized in allergic disease states. However, FeNO is also involved in nonallergic inflammatory and pulmonary vascular mechanisms or responses to environmental stimuli. We sought to determine the extent to which obesity or sedentary lifestyle is associated with FeNO in adolescents not selected on the basis of allergic disease. In Project Viva, a prebirth cohort study, we measured body mass index (BMI), skinfold thicknesses, waist circumference, body fat, hours watching television, hours of physical activity, and heart rate after exercise among 929 adolescents (median age, 12.9). We measured FeNO twice and averaged these as a continuous, log-transformed outcome. We performed linear regression models, adjusted for child age, sex, height, and race/ethnicity, maternal education and smoking during pregnancy, household income and smoking, and neighbourhood characteristics. In secondary analysis, we additionally adjusted for asthma. More than 2 hours spent watching TV was associated with 10% lower FeNO (95% confidence interval [CI]: -20, 0%). Higher body fat percentage was also associated with lower FeNO. After additional adjustment for asthma, teens who are underweight (BMI <5th %tile, 3%) had 22% lower FeNO (95%CI: -40, 2%) and teens who are overweight (BMI ≥85th %ile, 28%) had 13% lower FeNO (95%CI: -23, -2%). Each of these associations of lifestyle and body weight with lower FeNO were greater in magnitude after adjusting for asthma. In summary, sedentary lifestyle, high and low BMI were all associated with lower FeNO in this adolescent cohort.

Factors influencing breath analysis results in patients with diabetes mellitus

Breath analysis is used to detect the composition of exhaled gas. As a quick and non-invasive detection method, breath analysis provides deep insights into the progression of various kinds of diseases, especially those with metabolism disorders. Abundant information on volatile compounds in diabetic patients has been studied in numerous articles in the literature. However, exhaled gas in diabetic patients can be altered by various complications. So far, little attention has been paid to this alteration. In our paper, we found that under air pollution conditions, diabetic patients exhale more nitric oxide. Diabetic patients with heart failure exhale more acetone than those without heart failure. After ¹³C-labeled glucose intake, patients infected with Helicobacter pylori exhaled more ¹³C and less ¹⁸O than those without infection. Exhalation with chronic kidney disease changes volatile organic compounds on a large scale. Diabetic patients with ketoacidosis exhale more acetone than those without ketoacidosis. Some specific volatile organic compounds also emanate from diabetic feet. By monitoring breath frequency, diabetic patients with obstructive sleep apnea syndrome exhibit a unique breath pattern and rhythm as compared with other diabetic patients, and sleep apnea is prevalent among diabetic patients. In addition to clinical findings, we analyzed the underlying mechanisms at the levels of molecules, cells and whole bodies, and provided suggestions for further studies.

Source-specific pollution exposure and associations with pulmonary response in the Atlanta Commuters Exposure Studies

Concentrations of traffic-related air pollutants are frequently higher within commuting vehicles than in ambient air. Pollutants found within vehicles may include those generated by tailpipe exhaust, brake wear, and road dust sources, as well as pollutants from in-cabin sources. Source-specific pollution, compared to total pollution, may represent regulation targets that can better protect human health. We estimated source-specific pollution exposures and corresponding pulmonary response in a panel study of commuters. We used constrained positive matrix factorization to estimate source-specific pollution factors and, subsequently, mixed effects models to estimate associations between source-specific pollution and pulmonary response. We identified four pollution factors that we named: crustal, primary tailpipe traffic, non-tailpipe traffic, and secondary. Among asthmatic subjects (N = 48), interquartile range increases in crustal and secondary pollution were associated with changes in lung function of -1.33% (95% confidence interval (CI): -2.45, -0.22) and -2.19% (95% CI: -3.46, -0.92) relative to baseline, respectively. Among non-asthmatic subjects (N = 51), non-tailpipe pollution was associated with pulmonary response only at 2.5 h post-commute. We found no significant associations between pulmonary response and primary tailpipe pollution. Health effects associated with traffic-related pollution may vary by source, and therefore some traffic pollution sources may require targeted interventions to protect health.

Acute changes in a respiratory inflammation marker in guards following Beijing air pollution controls

The adverse respiratory health effects of PM_2.5 have been studied. However, the epidemiological evidence for the association of specific PM_2.5 sources with health outcomes is still limited. This study investigated the association between PM_2.5 components and sources with a biomarker of acute respiratory inflammation (FeNO) in guards. Personal exposure was estimated by microenvironment samplers and FeNO measurements were carried out before, during and after the Victory Day Military Parade in Beijing. Four sources were determined by factor analysis, including urban pollution, dust, alloy steel abrasion and toxic metals. A mixed-effect model was used to estimate the associations of FeNO with PM_2.5 sources and chemical constituents, controlling for age, BMI, smoke activity, physical activity, waist circumference, temperature and relative humidity. In summary, large concentration decreases in PM_2.5 concentration and PM_2.5 chemical constituents were observed in both roadside and indoor environments during the air control periods, immediately followed by statistically significant decreases in FeNO of roadside guards and patrol guards. Besides, statistically significant increases in FeNO were found to be associated with interquartile range (IQR) increases in some pollutants, with an increase of 1.45ppb (95% CI: 0.69, 2.20), 0.65ppb (95% CI: 0.13, 1.17), 1.48ppb (95% CI: 0.60, 2.35), 0.82ppb (95% CI: 0.44, 1.20), 0.77ppb (95% CI: 0.42, 1.11) in FeNO for mass, sulfate, BC, Ca²⁺ and Sm, respectively. In addition, compared to alloy steel abrasion and toxic metals, urban pollution and dust factors were more associated with acute airway inflammation for highly-exposed populations.

Comparison of normal and dusty day impacts on fractional exhaled nitric oxide and lung function in healthy children in Ahvaz, Iran

Children are the vulnerable group at risk of adverse health effects related to air pollution due to dust storm in Ahvaz. The purpose of this study was to compare the values of fractional exhaled nitric oxide (FENO) and lung functions as parameters of adverse health effects of particulate matter (PM) in dusty and normal (non-dusty) days in elementary schoolchildren. The study was conducted among elementary school students in Ahvaz. The healthy elementary schoolchildren (N = 105) were selected from different districts for FENO and lung function sampling during the dusty and normal days. The values of PM₁₀ and PM_2.5 during dusty days were higher than during normal days. Mean values of FENO during the normal and dusty days were 14.23 and 20.3 ppb, respectively, and the difference between these values was statistically significant (p < 0.05). Lung function results showed a statistically significant difference between the mean values of forced vital capacity during the dusty and normal days (p < 0.05). The results revealed a significant difference both in the values of inflammatory biomarker and in the lung function tests in dusty and normal days. Based on our results, fractional exhaled nitric oxide could be a useful short-term biomarker of particulate pollution effect coupled with spirometry.