Biomass Smoke Research Articles

ẢNH HƯỞNG CỦA Ô NHIỄM KHÔNG KHÍ TỚI TRẺ EM KHUYẾT TẬT: NGHIÊN CỨU TỔNG QUAN DIỄN NGÔN

Air pollution is one of the global problems with adverse effects on many aspects of human life, on different population groups and on the ecology of animals and plants. The effects of air pollution on disadvantaged communities in society such as children with disabilities are also considered. This paper describes the research results on the effects of air pollution on children with disabilities through narrative review and content analysis from 39 articles published from 2010 to 2020. Results showed that most studies were conducted in developed countries from the large survey sample sizes in wide age ranges from from pregnancy to 19 years of age in longitudinal, cross-sectional and retrospective study designs. Air pollution is determined based on the indicators of nitrogen dioxide (NO2), black carbon (BC), fine particulate matter (PM) such as PM1, PM2.5, PM10, sulfur dioxide (SO2), polycyclic aromatic hydrocarbon (PAH), benzene, ground-level ozone and solid biomass smoke. Results from the review showcased that air pollution has an effect on a high risk of autism spectrum disorders, attention deficit hyperactivity disorder, intellectual disability, behavioral and emotional disorders including depression and psychosis. In addition, studies have also shown that air pollution has serious effects on children's brain development and physical health such as impaired fetal neural development, premature brain imbalance, inflammation, and changes in fetal brain structure. Showing the relationship between air pollution and children's disability may indicate that environmental pollution is considered as a factor that negatively affects the disability etiology and severity. Showing this relationship contributes to promoting environmental protection, reducing pollution including air pollution at national and global scale.

The effect of air pollution on the transcriptomics of the immune response to respiratory infection

Combustion related particulate matter air pollution (PM) is associated with an increased risk of respiratory infections in adults. The exact mechanism underlying this association has not been determined. We hypothesized that increased concentrations of combustion related PM would result in dysregulation of the innate immune system. This epidemiological study includes 111 adult patients hospitalized with respiratory infections who underwent transcriptional analysis of their peripheral blood. We examined the association between gene expression at the time of hospitalization and ambient measurements of particulate air pollutants in the 28 days prior to hospitalization. For each pollutant and time lag, gene-specific linear models adjusting for infection type were fit using LIMMA (Linear Models For Microarray Data), and pathway/gene set analyses were performed using the CAMERA (Correlation Adjusted Mean Rank) program. Comparing patients with viral and/or bacterial infection, the expression patterns associated with air pollution exposure differed. Adjusting for the type of infection, increased concentrations of Delta-C (a marker of biomass smoke) and other PM were associated with upregulation of iron homeostasis and protein folding. Increased concentrations of black carbon (BC) were associated with upregulation of viral related gene pathways and downregulation of pathways related to antigen presentation. The pollutant/pathway associations differed by lag time and by type of infection. This study suggests that the effect of air pollution on the pathogenesis of respiratory infection may be pollutant, timing, and infection specific.

Risk of anaemia among women engaged in biomass-based fish smoking as their primary livelihood in the central region of Ghana: a comparative cross-sectional study

BackgroundFish smoking using biomass fuel is an important livelihood for women living in the coastal regions of Ghana and may contribute to anaemia risk. We assessed whether women who smoke fish as their primary livelihood are at increased risk of anaemia compared to women in other livelihoods in the Central Region of Ghana.MethodsWe conducted a comparative cross-sectional study of 330 randomly selected adult women (18–49 years) whose primary livelihood was either fish smoking (FSL) involving the burning of biomass fuel (n = 175) or other livelihoods (OL) not involving burning of firewood (n = 155). Data on participants’ recent diet were collected from a single, quantitative 24-h dietary recall and qualitative 7-day food frequency questionnaire of animal-source food (ASF) consumption. We further assessed participants’ haemoglobin concentration using the Urit 12 Hemocue system. We compared total iron intakes, the proportion of dietary iron from animal and plant sources, mean haemoglobin concentrations, and anaemia prevalence between FSL and OL women.ResultsFish was the most frequently consumed ASF by both groups of women. Although OL women consumed more diverse ASFs in the past week compared with the FSL women (3.4 ± 1.2 vs. 2.7 ± 1.3; p < 0.001), the contribution of ASFs to total iron intake in the past day was greater for the FSL women (49.5% vs. 44.0%; p = 0.030). Estimated total dietary iron intake in the past day was generally low (5.2 ± 4.7 mg) and did not differ by group. The unadjusted prevalence of anaemia was 32 and 27.1% among the FSL and OL women, respectively (p = 0.33). After covariates adjustment, the FSL women had statistically higher anaemia prevalence (36.4% vs. 20.5%; p = 0.032) and 80% greater risk of being anemic (RR: 1.8; 95% CI: 1.1, 3.0) than the OL women.ConclusionWomen who use biomass fuel to smoke fish as their primary livelihood had an increased risk of anaemia. Furthermore, the average 24-h dietary iron intake among both the FSL and OL women was below their daily iron requirement. Interventions to enhance women’s dietary iron intake and reduce their livelihood related biomass smoke exposure may be warranted in this population.

Lung Features in Individuals with Biomass Smoke Exposure Characterized by CT Scan and Changes in Pulmonary Function.

Background and ObjectiveTo determine the effects of BSE (biomass smoke exposure) on pulmonary and non-pulmonary changes in patients with COPD compared with normal individuals.MethodsUsing a cohort, we recruited 16 healthy individuals with BSE (BSE normal), 19 patients with BSE+COPD, 13 healthy individuals with cigarette smoke exposure (CSE normal), 25 patients with CSE+COPD, and 25 healthy controls. Patients with GOLD stage I and II COPD were included. Baseline data (demographic data, BSE or CSE, lung function, and CT findings) and follow-up lung function data were collected. CT parameters of emphysema, pulmonary small vessels, airway remodeling, pectoralis muscles, and erector spinae muscle were measured.ResultsIndividuals with BSE were mainly women (32/35, 91.43%). Compared with the CSE+COPD group, the BSE+COPD group demonstrated slower lung function decline, increased lower lung emphysema, narrower airway lumen dimensions and increased airway wall thickening in the moderate and small airways (all P<0.05). Compared with healthy controls, the CSE normal and BSE normal groups exhibited significant reductions in pulmonary small vessel area and obvious airway remodeling in small airways (P<0.05). Compared with the BSE normal group, the BSE+COPD group showed significantly more severe emphysema and airway remodeling, as well as reduced left pectoralis major muscle area (all P<0.05).ConclusionHealthy individuals with BSE had reduced pulmonary small vessel area and evidence of airway remodeling; patients with BSE and COPD showed more severe emphysema, airway remodeling, and reductions in pectoralis major muscle area.Clinical Trial RegistrationChiCTR-OO-14004264.

Circulating Secretoglobin Family 1A Member 1 (SCGB1A1) Levels as a Marker of Biomass Smoke Induced Chronic Obstructive Pulmonary Disease.

Secretoglobin family 1A member 1 (SCGB1A1) alternatively known as club cell protein 16 is a protective pneumo-protein. Decreased serum levels of SCGB1A1 have been associated with tobacco smoke induced chronic obstructive pulmonary disease (TS-COPD). Exposure to biomass smoke (BMS) is an important COPD risk factor among women in low and lower-middle income countries. Therefore, in a cross-sectional study (n = 50/group; total 200 subjects) we assessed serum SCGB1A1 levels in BMS-COPD subjects (11 male, 39 female) compared to TS-COPD (all male) along with TS-CONTROL (asymptomatic smokers, all male) and healthy controls (29 male, 21 female) in an Indian population. Normal and chronic bronchitis like bronchial mucosa models developed at the air–liquid interface using human primary bronchial epithelial cells (3 donors, and three replicates per donor) were exposed to cigarette smoke condensate (CSC; 0.25, 0.5, and 1%) to assess SCGB1A1 transcript expression and protein secretion. Significantly (p < 0.0001) decreased serum SCGB1A1 concentrations (median, interquartile range, ng/mL) were detected in both BMS-COPD (1.6; 1.3–2.4) and TS-COPD (1.8; 1.4–2.5) subjects compared to TS-CONTROL (3.3; 2.9–3.5) and healthy controls (5.1; 4.5–7.2). The levels of SCGB1A1 were positively correlated (r = 0.7–0.8; p < 0.0001) with forced expiratory volume in 1 s, forced vital capacity, their ratios, and exercise capacity. The findings are also consistent within the BMS-COPD sub-group as well. Significantly (p < 0.03) decreased SCGB1A1 concentrations were detected with severity of COPD, dyspnea, quality of life, and mortality indicators. In vitro studies demonstrated significantly (p < 0.05) decreased SCGB1A1 transcript and/or protein levels following CSC exposure. Circulating SCGB1A1 levels may therefore also be considered as a potent marker of BMS-COPD and warrant studies in larger independent cohorts.

Source-specific light absorption by carbonaceous components in the complex aerosol matrix from yearly filter-based measurements

Abstract. Understanding the sources of light-absorbing organic (brown) carbon (BrC) and its interaction with black carbon (BC) and other non-refractory particulate matter (NR-PM) fractions is important for reducing uncertainties in the aerosol direct radiative forcing. In this study, we combine multiple filter-based techniques to achieve long-term, spectrally resolved, source- and species-specific atmospheric absorption closure. We determine the mass absorption efficiency (MAE) in dilute bulk solutions at 370 nm to be equal to 1.4 m2 g−1 for fresh biomass smoke, 0.7 m2 g−1 for winter-oxygenated organic aerosol (OA), and 0.13 m2 g−1 for other less absorbing OA. We apply Mie calculations to estimate the contributions of these fractions to total aerosol absorption. While enhanced absorption in the near-UV has been traditionally attributed to primary biomass smoke, here we show that anthropogenic oxygenated OA may be equally important for BrC absorption during winter, especially at an urban background site. We demonstrate that insoluble tar balls are negligible in residential biomass burning atmospheric samples of this study and thus could attribute the totality of the NR-PM absorption at shorter wavelengths to methanol-extractable BrC. As for BC, we show that the mass absorption cross-section (MAC) of this fraction is independent of its source, while we observe evidence for a filter-based lensing effect associated with the presence of NR-PM components. We find that bare BC has a MAC of 6.3 m2 g−1 at 660 nm and an absorption Ångström exponent of 0.93 ± 0.16, while in the presence of coatings its absorption is enhanced by a factor of ∼ 1.4. Based on Mie calculations of closure between observed and predicted total light absorption, we provide an indication for a suppression of the filter-based lensing effect by BrC. The total absorption reduction remains modest, ∼ 10 %–20 % at 370 nm, and is restricted to shorter wavelengths, where BrC absorption is significant. Overall, our results allow an assessment of the relative importance of the different aerosol fractions to the total absorption for aerosols from a wide range of sources and atmospheric ages. When integrated with the solar spectrum at 300–900 nm, bare BC is found to contribute around two-thirds of the solar radiation absorption by total carbonaceous aerosols, amplified by the filter-based lensing effect (with an interquartile range, IQR, of 8 %–27 %), while the IQR of the contributions by particulate BrC is 6 %–13 % (13 %–20 % at the rural site during winter). Future studies that will directly benefit from these results include (a) optical modelling aiming at understanding the absorption profiles of a complex aerosol composed of BrC, BC and lensing-inducing coatings; (b) source apportionment aiming at understanding the sources of BC and BrC from the aerosol absorption profiles; (c) global modelling aiming at quantifying the most important aerosol absorbers.

Multisite characterization of concurrent black carbon and biomass burning around COVID-19 lockdown period

The Magee Scientific Model AE33 Next Generation Aethalometer, installed at Amity University Haryana (AUH), Panchgaon (rural station) has been operated round-the-clock and obtained high-resolution (1–5 Minutes) observations of Black Carbon (BC) mass concentration at seven different sensing wavelengths (ranging from UV to NIR). For each observation, contribution from Biomass Burning (BB, in percent) to the BC has also been recorded. These measurements have been analyzed to segregate different sources, responsible for BC at this rural station. The results reveal that the major contributor is ‘traffic’ (fossil-fuel diesel emissions), followed by ‘biomass smoke’, wood-burning activities. The diurnal variation in BC and associated BB over this study area reveals a significant maximum around 0900 h and minimum around 1600 h. These maximum and minimum concentrations are attributed to transport activities during morning and ascending of local atmospheric boundary-layer height. The results also exhibit a strong affinity between BC mass concentration and coincident CO2 and PM2.5 mass concentrations. Synchronous BC measurements have also been organized over two more locations, namely, Bhopal (urban station) and Mahabaleshwar (high-altitude station). The black carbon aerosol transport through long-range air mass back-trajectories is explained.

What are the Differences Between Smoker and Non-smoker COPD Cases? Is it a Different Phenotype?

The most important risk factor for chronic obstructive pulmonary disease (COPD) is smoking. However, more than 25% of patients do not have a history of smoking. The intent of this study is to identify characteristics of COPD patients that are non-smokers. The records of patients with COPD were retrospectively reviewed. Smoking history, comorbidities, exacerbations, biomass, and environmental tobacco smoke (ETS) exposures were identified. Also, age, gender, pulmonary function test (PFT) values, modified Medical Research Council (mMRC) dyspnea scores were recorded. Non-smokers exposed to any of the COPD risk factors above were grouped and the data were analyzed to determine the specific characteristics of COPD that applied to them. A total of 706 COPD patients were analyzed with a mean age of 67.2 ± 9.4. Of these patients, 93 (13.2%) were female and 613 (86.8%) were male. Of the 706 patients, 128 (18.1%) were non-smokers. The percentage of male patients having COPD was significantly lower in the non-smoker group (P < .001). However, biomass, ETS exposure in childhood, and a history of previous respiratory infection were significantly higher in the non-smoker group (P < .001). The mean body mass index (BMI) was greater in non-smokers than smokers. Non-smokers with COPD have more biomass, ETS exposure, and infection history in childhood. They also have less impairment of airflow limitation, better symptom scores, and greater BMIs. Smoking history can be used to determine a different phenotype.

Cardiorespiratory Toxicity of Biomass Pollutants

Traditional biomass alone accounts for 8.5% of global energy consumption and exclusively covers the energy needs of nearly 3 billion people and 1.2 billion of whom do not yet have access to electricity. The smoke resulting from the combustion of this biomass contains various gases having harmful effects on health. This work aims to evaluate the toxic effects of carbon monoxide, methane and hydrogen sulfide on biochemical and cardiorespiratory parameters of Wistar rats. The complete blood count, C-reactive protein, lipid profile and histology of the lungs are evaluated after subchronic exposure to biomass smoke. The results showed a decrease in red blood cells (p = 0.004), an increase in blood platelets, an increase in C - reactive protein (p = 0.003) and triglycerides (p = 0.0041) and a decrease in HDL (p = 0, 0215) after 28 days of exposure. Exposure to smoke from biomass is therefore a source of alteration of cardiorespiratory parameters.

The “Slow Horse Racing Effect” on Lung Function in Adult Life in Chronic Obstructive Pulmonary Disease Associated to Biomass Exposure

Although different trajectories in lung function decline have been identified in patients with COPD associated to tobacco exposure (TE-COPD), genetic, environmental, and infectious factors affecting lung function throughout life have not been fully elucidated in patients with COPD associated to biomass (BE-COPD). In this review, we present current epidemiological findings and notable advances in the natural history of lung decline in BE-COPD, as well as conditions modeling the FEV1 trajectory, such as health insults, during the first years of childhood. Evidence shows that women exposed to biomass smoke reach adult life with a lower FEV1 than expected. However, in contrast to the “horse racing effect” predicting an excessive lung-function decline in forthcoming years, as observed in smokers, this decline is slower in non-smokers, and no rapid decliners are observed. Accordingly, BE-COPD might be considered another phenotype of COPD based on assessments of lung function decline. Likewise, other functional and clinical aspects described in this review suggest that this condition might be similar to TE-COPD. More research is needed to fully characterize this subgroup of variants of COPD.

Exposure to biomass smoke induces pulmonary Th17 cell differentiation by activating TLR2 on dendritic cells in a COPD rat model

Almost three billion people in developing countries are exposed to biomass smoke (BS), which predisposes them to developing chronic obstructive pulmonary disease (COPD). COPD is associated with abnormal innate and adaptive immune responses in the lungs and systemic circulation, but the mechanisms underlying BS-COPD development are uncertain. We investigated the role of dendritic cells (DCs) and interleukin (IL)-17A in BS-COPD. We investigated T helper cell responses in the BS-exposed COPD rat model by flow cytometry, quantitative PCR, and enzyme-linked immunosorbent assays. We conducted ex vivo experiments to determine which antigen-presenting cells induce Th17 cell responses. We evaluated the in vitro effects of BS-related particulate matter (BRPM) (2.5 μm) on the function of bone marrow-derived dendritic cells (BMDCs). We found that BS exposure enhanced Th17 responses in the lungs of the COPD-modelled rats, and the stimulated DCs (but not the macrophages) were sufficient to induce naïve CD4 + T cells to produce IL-17A in ex vivo experiments. BRPM significantly enhanced the maturation and activation of DCs through Toll-like receptor 2 (TLR2), but not TLR4, and induced Th17 responses. Therefore, BS activated lung DCs through TLR2, which led to Th17 responses and emphysema in the rats. This process is possibly therapeutically targetable.

Zebrafish irritant responses to wildland fire-related biomass smoke are influenced by fuel type, combustion phase, and byproduct chemistry

ABSTRACT Human exposure to wildfire-derived particulate matter (PM) is linked to adverse health outcomes; however, little is known regarding the influence of biomass fuel type and burn conditions on toxicity. The aim of this study was to assess the irritant potential of extractable organic material (EOM) of biomass smoke condensates from five fuels (eucalyptus, pine, pine needle, peat, or red oak), representing various fire-prone regions of the USA, burned at two temperatures each [flaming (approximately 640°C) or (smoldering approximately 500°C)] using a locomotor assay in zebrafish (Danio rerio) larvae. It was postulated that locomotor responses, as measures of irritant effects, might be dependent upon fuel type and burn conditions and that these differences relate to combustion byproduct chemistry. To test this, locomotor activity was tracked for 60 min in 6-day-old zebrafish larvae (25–32/group) immediately after exposure to 0.4% dimethyl sulfoxide (DMSO) vehicle or EOM from the biomass smoke condensates (0.3–30 µg EOM/ml; half-log intervals). All EOM samples produced concentration-dependent irritant responses. Linear regression analysis to derive rank-order potency indicated that on a µg PM basis, flaming pine and eucalyptus were the most irritating. In contrast, on an emission-factor basis, which normalizes responses to the amount of PM produced/kg of fuel burned, smoldering smoke condensates induced greater irritant responses (>100-fold) than flaming smoke condensates, with smoldering pine being the most potent. Importantly, irritant responses significantly correlated with polycyclic aromatic hydrocarbon (PAH) content, but not with organic carbon or methoxyphenols. Data indicate that fuel type and burn condition influence the quantity and chemical composition of PM as well as toxicity.

POS0482 WOOD SMOKE EXPOSURE IS ASSOCIATED WITH HIGHER ANTI-CCP ANTIBODY TITERS IN HISPANIC PATIENTS WITH RHEUMATOID ARTHRITIS

Background:Wood smoke exposure is a risk factor for the development of chronic obstructive pulmonary disease (COPD), lung cancer and cardiovascular disease and it has also been linked to higher anti-CCP antibodies in patients with rheumatoid arthritis (RA) and COPD (1).Objectives:The objective of the present study is to report the correlation between anti-CCP, IgG, IgM and IgA rheumatoid factor (RF) to wood smoke exposure in patients with RA. Additionally, evaluate the impact of disease activity, biomass exposure, and disease duration on anti-CCP antibody levels.Methods:A cross-sectional, observational study was designed based on a cohort of Hispanic RA patients. All fulfilled the 2010 ACR/EULAR classification criteria for RA. Biomass smoke exposure was expressed using the biomass exposure index (BEI) calculated from the mean of exposed hours per day multiplied by the number of years exposed. Subjects were divided into two groups: those exposed to wood smoke with BEI ≥1 and subjects not exposed to wood smoke. They were matched by age, gender, and comorbidities. Anti-CCP antibodies and RF were measured by ELISA with cutoff points of &lt;5 U/mL and &lt;20 U/mL respectively.Results:A total of 318 subjects were included, 159 (50%) of them had a history of exposure to wood smoke. Anti-CCP antibody positivity was present in 102 (64.2%) with a median titer of 97.1 U/mL (1.7-198) in the RA exposed group, and in 89 (56%) with a median titer of 8.5 U/mL (1.1-145) in the RA non-exposed group. A significant difference was found in anti-CCP antibody titers between groups (p=0.003). (Table 1). Spearman’s rho showed a small but statistically significant correlation between BEI and anti-CCP antibody titers (rho= 0.170, p=0.002). Biomass exposure was independently related to higher anti-CCP antibody titers (B=35.4, p&lt;0.001).Conclusion:RA patients who were exposed to wood smoke had higher titers of anti-CCP antibodies than non-exposed RA patients. Furthermore, biomass exposure was shown to be independently related to higher titers of anti-CCP antibodies.

Association of Exposure to Biomass Smoke with Reduced Pulmonary Functions in Rural School Children- A Cross-sectional Study Findings

Background: Children are at higher risk of developing respiratory diseases when they expose to biomass smoke. Very few studies have compared the duration of exposure to pulmonary function tests in children. The purpose of the study was to observe the effect of biomass fuel smoke on respiratory functions in 40 school-going children aged between 7 to 14 years and to compare these parameters with 40 age and sex-matched healthy children of the same school, and correlate their duration of exposure through pulmonary function tests. Methods: This prospective cross-sectional study was carried out over six months (August 2018 to January 2019). The selection of the study population was carried out from one of the Government primary schools. Eighty students participated in the study. The study population was divided into two groups. Group-1 consisted of 40 school children exposed to biomass smoke aged between 7 to 14 years as cases. Group-2 consisted of the same number of sex and age-matched controls who had no exposure to biomass smoke. After the relevant history, questionnaire, and respiratory examinations, children were subjected to spirometry. Schiller’s Spirovit-SP1 was also used. Results: The prevalence of some of the respiratory symptoms in biomass smokers was significant compared to non-smokers. There was a significant 1.125 fold reduction in FVC (p=0.003*) and 1.195 fold reduction in FEV1 (p=0.000*) in smokers compared to non-smokers. A significant correlation existed between duration of exposure to FVC (r=-0.508 p=0.001) and FEV1 (r=-0.462 p=0.005). Conclusions: We concluded that biomass smoke significantly reduced FVC and FEV1 in children, and these parameters are negatively correlated with the number of hours of exposure.

The prevalence of Asthma-Copd Overlap Syndrome In Women Patients With Biomass Fuel Utilizing

Objective: Asthma-chronic obstructive pulmonary disease overlap (ACO) indicates that its characteristics with pulmonary exaggerated reactivity and airflow limitation chronically. We aimed to investigate the differences among women non smoker participants who have asthma, chronic obstructive pulmonary disease (COPD) and ACO with biomass smoke exposure.&#x0D; Method: Patients were examined at the outpatient clinic from September 2017 to March 2020. Non-smoker women patients aged ≥40 years, diagnosed with obstructive pulmonary disease were included in the study. pulmonary function tests (PFT), early reversibility testing (bronchodilator test), and sputum eosinophil analysis were performed to all patients.&#x0D; Results: A total of 102 patients were included. The mean age was 46.95±9.50 years. In the differential diagnosis, 65 patients (63.7%) had asthma and 37 patients (36.3%) had COPD. Among COPD patients, 10 (27.0%) were diagnosed with ACO. The actual prevalence rates of COPD and ACO were 26.5% and 9.8%, respectively. Poisson regression analysis showed that COPD compared to asthma, while holding the others variable constant in the model, are expected to have 2.976 times greater rate for exacerbations.( IRR, 95%CI ,2.976 (0.687 to 1.494), 5.296 (1.203 to 2.130), P&lt;0.001, Coef. 1.091, 1.667 respectively). Logistic Regression analysis demonstrated that, the count of sputum, blood eosinophil and total IgE results were correlated with the exacerbation times.&#x0D; Conclusion: Biomass smoke exposure in the women population is revealed as a significant factor for the diagnosis of ACO.

Prevalence of Risk Factors and Pharmacotherapeutic Management of COPD in Elderly Patients

Chronic obstructive pulmonary disease (COPD) is the most common illness in the elderly population. Treating elderly patients is a challenge for physicians because of the co-existence of multi-morbidities, which increases the number of prescribed medications among these patients. The objectives of this study were to identify prevalence of associated risk factors and to evaluate pharmacotherapeutic management of COPD in elderly patients. A prospective, observational study was conducted from January 2019 to December 2019 in the department of pulmonary medicine of a tertiary care teaching hospital in Bangalore, India. A total of 136 elderly patients diagnosed with COPD aged above 65 years who consented to take part in the study and fulfilled study criteria were enrolled. A well designed and internally validated case report form was used to document the findings after a due approval obtained from the Institutional Ethics Committee. Socio-demographic characteristics, prescribed medications, risk factor and clinical characteristics were documented and analyzed. Out of 136 elderly patients, 52.21% were male while 47.79% were female. The mean age of the participants was 70.68±5.08 (SD) years. Amongst the study patients 48.53% had other comorbidities. The major risk factors associated with COPD were smoking (38.97%), biomass fuel exposure (16.91%) and occupational exposure (36.76%). Treatment with antibiotic combination therapy was observed in 48.53% of patients, 46.32% with antibiotic monotherapy followed by 4.41% with escalation of therapy. It is evident from this study that the prevalence of risk factors such as age, cigarette smoking, exposure to biomass smoke and occupation plays a role in the development of COPD and it requires a rational approach in the management of COPD in the elderly patients.

Differences between cigarette smoking and biomass smoke exposure: An in silico comparative assessment of particulate deposition in the lungs

Cigarette smoking and biomass smoke are the two main environmental risk factors of chronic obstructive pulmonary disease (COPD) worldwide. However, it remains unclear why these exposures result in two different disease phenotypes. In this study, we assessed the lung deposition from biomass and cigarette smoke exposures and examined whether differences due to inherently different particle size distributions and inhalation conditions may contribute to the differences between biomass- and tobacco-related COPD phenotypes. Using high-fidelity three-dimensional computational fluid-particle dynamics in a representative upper airway geometry, coupled to one-dimensional models of the lower airways, we computed total deposited doses and examined regional deposition patterns based on exposure data from a randomized control trial in Peru and from the literature for biomass and mainstream cigarette smoke, respectively. Our results showed that intrathoracic deposition was higher in cigarette smoking, with 36.8% of inhaled biomass smoke particles and 57.7% of cigarette smoke particles depositing in the intrathoracic airways. We observed higher fractions of cigarette smoke particles in the last few airway generations, which could explain why cigarette smoking is associated with more emphysema than biomass smoke exposure. Mean daily deposited dose was two orders of magnitude higher in cigarette smoking. Lobar distributions of the deposited dose also differed, with the left lower and right upper lobes receiving the highest doses of biomass and cigarette smoke particles, respectively. Our findings suggest that the differences between biomass- and tobacco-related COPD could, at least in part, be due to differences in total and regional lung deposition of biomass and cigarette smoke.

Inflammatory Biomarkers Interleukin 1 Beta (IL-1β) and Tumour Necrosis Factor Alpha (TNF-α) Are Differentially Elevated in Tobacco Smoke Associated COPD and Biomass Smoke Associated COPD.

Chronic obstructive pulmonary disease (COPD), the leading cause of mortality and morbidity worldwide, is characterized by abnormal activation of inflammatory cells. The increased pro-inflammatory cytokines, such as tumour necrosis factor alpha (TNF-α) and interleukin 1 beta (IL-1β), further amplify the inflammation. We evaluated the dose response relationship of IL-1β and TNF-α levels and severity of airflow limitation, and differential responses in IL-1β and TNF-α between biomass COPD (BMS-COPD) and tobacco smoke COPD (TS-COPD) using a case control design in 160 subjects. Patients with COPD had higher serum levels of both IL-1β and TNF-α compared to healthy controls. A large difference in TNF-α was observed between TS-COPD and BMS-COPD, where TS-COPD patients had much higher levels. Serum IL-1β levels were higher in BMS-COPD. Levels of IL-1β correlated better with severity of airflow limitation than TNF-α levels. Both TNF-α and IL-1β levels had a negative linear relationship with Forced Expiratory Volume in 1st second (FEV1) and six-minute walk distance. The correlations were stronger with FEV1 than six-minute walk distance. The correlations of TNF-α and IL-1β with St George Respiratory Questionnaire (SGRQ) scores and body mass index (BMI) were not significant. In conclusion, the levels of pro-inflammatory cytokines TNF-α and IL-1β are differently elevated in TS-COPD and BMS-COPD, respectively.

Effectiveness of low-dose theophylline for the management of biomass-associated COPD (LODOT-BCOPD): study protocol for a randomized controlled trial

BackgroundCOPD is a leading cause of death globally, with the majority of morbidity and mortality occurring in low- and middle-income country (LMIC) settings. While tobacco-smoke exposure is the most important risk factor for COPD in high-income settings, household air pollution from biomass smoke combustion is a leading risk factor for COPD in LMICs. Despite the high burden of biomass smoke-related COPD, few studies have evaluated the efficacy of pharmacotherapy in this context. Currently recommended inhaler-based therapy for COPD is neither available nor affordable in most resource-limited settings. Low-dose theophylline is an oral, once-a-day therapy, long used in high-income countries (HICs), which has been proposed for the management of COPD in LMICs in the absence of inhaled steroids and/or bronchodilators. The Low-dose Theophylline for the Management of Biomass-Associated COPD (LODOT-BCOPD) trial investigates the clinical efficacy and cost-effectiveness of low-dose theophylline for the management of biomass-related COPD in a low-income setting.MethodsLODOT-BCOPD is a randomized, double-blind, placebo-controlled trial to test the efficacy of low-dose theophylline in improving respiratory symptoms in 110 participants with moderate to severe COPD in Central Uganda. The inclusion criteria are as follows: (1) age 40 to 80 years, (2) full-time resident of the study area, (3) daily biomass exposure, (4) post-bronchodilator FEV1/FVC below the 5th percentile of the Global Lung Initiative mixed ethnic reference population, and (5) GOLD Grade B-D COPD. Participants will be randomly assigned to receive once daily low-dose theophylline (200 mg ER, Unicontin-E) or placebo for 52 weeks. All participants will receive education about self-management of COPD and rescue salbutamol inhalers. We will measure health status using the St. George’s Respiratory Questionnaire (SGRQ) and quality of life using the EuroQol-5D (EQ-5D) at baseline and every 6 months. In addition, we will assess household air pollution levels, serum inflammatory biomarkers (fibrinogen, hs-CRP), and theophylline levels at baseline, 1 month, and 6 months. The primary outcome is change in SGRQ score at 12 months. Lastly, we will assess the cost-effectiveness of the intervention by calculating quality-adjusted life years (QALYs) from the EQ-5D.Trial registrationClinicalTrials.gov NCT03984188. Registered on June 12, 2019Trial acronymLow-dose Theophylline for the Management of Biomass-Associated COPD (LODOT-BCOPD)

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BACKGROUND Around half a million of people still rely on biomass fuels for cooking, which is a major source of household air pollution, associated with increased morbidity and mortality. Biomass smoke exposure is associated with airway obstruction and decreased ventilatory function. Though various studies are available in relation to biomass exposure and pulmonary function, literature is limited on lung age. Hence, the current study was undertaken to evaluate the effect of biomass fuel on pulmonary function and lung age in rural women and correlate biomass exposure index with the spirometry parameters and lung age. METHODS A cross sectional study was conducted in rural areas of Tamilnadu. Around 350 women were screened and 100 women aged &gt; 18 years with biomass exposure for at least five years and able to perform spirometry were selected for inclusion in the study. After obtaining consent, the subjects were evaluated further with detailed history and spirometry to record the lung function parameters and lung age. Biomass exposure index was calculated from hours spent in cooking per day multiplied with the years of cooking. RESULTS Mean age of the participants was 49.88 ± 10.76 years. 68 % had indoor kitchen with inadequate ventilation in 57 % of households. Majority of the women were housewives and belonged to the middle- and low-income groups. Around 19 % were symptomatic with cough and expectoration being predominant symptoms. Spirometry was abnormal in 83 % of the women and showed obstruction in majority. Mean forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), forced expiratory flow 25 - 75 % (FEF) and peak expiratory flow (PEF) were reduced in the study population. A significant negative correlation was observed between the biomass exposure index (BEI) hour-years and FEV 1 and FEF 25 % - 75 %. A significant positive correlation was observed between BEI hours-year and lung age. CONCLUSIONS Majority of the women exposed to biomass fuel smoke, though asymptomatic, had abnormal lung function with increased lung age. Intensity of exposure as measured by biomass exposure index correlated significantly with FEV1, FEF 25 - 75 % and lung age. Hence, regular surveillance of the women using biomass fuel for cooking should be done for early identification of respiratory impairment. KEY WORDS Biomass Exposure, Biomass Fuel, Pulmonary Function, Lung Age, Biomass Exposure Index