Prevalence of chronic obstructive pulmonary disease in rural women of Tamilnadu: implications for refining disease burden assessments attributable to household biomass combustion

Exploring the links between indoor air pollutants and health outcomes in South Asian countries: a systematic review

Indoor air pollution (IAP) has adverse effects on the health of people, globally. The objective of this systematic review was to present the range of health problems studied in association with indoor air pollutants in South Asian countries. We searched five databases, including PubMed, Web of Science, Scopus, Google Scholar, and CAB Direct for articles published between the years 2000 and 2020. We retrieved 5,810 articles, out of which we included 90 articles in our review. Among South Asian countries, only five countries have published results related to relationship between indoor air pollutants and adverse health conditions. All studies have shown adversity of indoor air pollutants on human's health. We found indoor solid fuel burning as a key source of indoor air pollution in the included studies, while women and children were most affected by their exposure to solid fuel burning. More than half of the studies accounted particulate matter responsible for indoor air pollution bearing negative health effects. In the included studies, eyes and lungs were the most commonly affected body organs, exhibiting common symptoms like cough, breathing difficulty and wheezing. This might have developed into common conditions like respiratory tract infection, chronic obstructive pulmonary diseases and eye cataract. In addition to promote research in South Asian countries, future research should focus on novel digital ways of capturing effects of indoor air pollutants among vulnerable segments of the population. As a result of this new knowledge, public health agencies should develop and test interventions to reduce people's exposure levels and prevent them to develop adverse health outcomes.

Prevalence of chronic obstructive pulmonary disease in Indian nonsmokers: a systematic review & meta-analysis

INTRODUCTION

Nonsmokers with chronic obstructive pulmonary disease (COPD) are neglected despite constituting half of all cases in studies from the developed world. Herein, we systematically reviewed the prevalence of COPD among nonsmokers in India.

CONTENT

We searched Embase, Scopus, and PubMed databases for studies examining the prevalence of COPD among nonsmokers in India. We used the Joanna Briggs Institute (JBI) checklist to assess included studies' quality. Meta-analysis was performed using random-effects model.

SUMMARY

Seven studies comprising 6,903 subjects were included. The quality of the studies ranged from 5/9 to 8/9. The prevalence of COPD varied between 1.6 and 26.6 %. Studies differed considerably in demographics and biomass exposure profiles of subjects. Among the four studies that enrolled both middle-aged and elderly Indian nonsmokers not screened based on biomass fuel exposure, the pooled prevalence of COPD was 3 % (95 % CI, 2-3 %; I2=50.52 %, p=0.11). The pooled prevalence of COPD among biomass fuel-exposed individuals was 10 % (95 % CI, 2-18 %; I2=98.8 %, p<0.001).

OUTLOOK

Limited evidence suggests a sizable burden of COPD among nonsmokers and biomass fuel-exposed individuals in India. More epidemiological studies of COPD in nonsmokers are needed from low and middle-income countries.

Issue 2 - "Update on adverse respiratory effects of indoor air pollution". Part 2): Indoor air pollution and respiratory diseases: Perspectives from Italy and some other GARD countries

OBJECTIVE

to synthesize the Italian epidemiological contribution to knowledge on indoor pollution respiratory impact, and to analyze the perspective of some GARD countries on the health effects of indoor air pollution.

RESULTS

Italian epidemiological analytical studies confirmed a strong relationship between indoor air pollution and health in general population. Environmental tobacco smoke, biomass (wood/coal) fuel for cooking/heating and indoor allergens (house dust mites, cat and dog dander, mold/damp) are the most relevant indoor pollution sources and are related to respiratory and allergic symptoms/diseases in Italy and in other GARD countries such as Mexico, Brazil, Vietnam, India, Nepal and Kyrgyzstan. Community-based global health collaborations are working to improve prevention, diagnosis and care of respiratory diseases around the world, specially in low- and middle-income countries, through research and education.

CONCLUSIONS

in the last thirty years, the scientific evidence produced on respiratory health effects of indoor air pollution has been extensive, but the necessity to empower the synergies between scientific community and local administrations remains a challenge to address in order to implement effective interventions. Based on abundant evidence of indoor pollution health effect, WHO, scientific societies, patient organizations and other members of the health community should work together to pursue the GARD vision of "a world where all people breathe freely" and encourage policy makers to increase their engagement in advocacy for clean air.

Critical review on emerging health effects associated with the indoor air quality and its sustainable management

Indoor air quality (IAQ) is one of the fundamental elements affecting people's health and well-being. Currently, there is a lack of awareness among people about the quantification, identification, and possible health effects of IAQ. Airborne pollutants such as volatile organic compounds (VOCs), particulate matter (PM), sulfur dioxide (SO2), carbon monoxide (CO), nitrous oxide (NO), polycyclic aromatic hydrocarbons (PAHs) microbial spores, pollen, allergens, etc. primarily contribute to IAQ deterioration. This review discusses the sources of major indoor air pollutants, molecular toxicity mechanisms, and their effects on cardiovascular, ocular, neurological, women, and foetal health. Additionally, contemporary strategies and sustainable methods for regulating and reducing pollutant concentrations are emphasized, and current initiatives to address and enhance IAQ are explored, along with their unique advantages and potentials. Due to their longer exposure times and particular physical characteristics, women and children are more at risk for poor indoor air quality. By triggering many toxicity mechanisms, including oxidative stress, DNA methylation, epigenetic modifications, and gene activation, indoor air pollution can cause a range of health issues. Low birth weight, acute lower respiratory tract infections, Sick building syndromes (SBS), and early death are more prevalent in exposed residents. On the other hand, the main causes of incapacity and early mortality are lung cancer, chronic obstructive pulmonary disease, and cardiovascular disorders. It's crucial to acknowledge anticipated research needs and implemented efficient interventions and policies to lower health hazards.

Impact of smokeless cooking fuel use on health status of women in a rural setting of eastern India

The sustainable development goals (SDG 7.1) reinforce to ensure that everyone has access to affordable, safe and renewable energy. In India, women are typically responsible for cooking and are most vulnerable to household air contaminants. We conducted a descriptive cross-sectional comparative study in Odisha, India between exclusive LPG (liquefied petroleum gas) users and non-LPG users. A total of 900 women, 450 from each group, were randomly selected. The LPG-users had a better predictor of physical, psychological, social, and environmental wellbeing than non-LPG users. We found the ophthalmic disorders (adjusted odds ratio (AOR) 2.87, 95% CI 1.16-7.10, p = .023), asthma (AOR 2.05, 95% CI 1.15-3.65, p = .015), and ALRI (acute lower respiratory infections) (AOR 9.19, 95% CI 2.06-40.96, p < .004) were significantly higher in non-LPG users in comparison to LPG users. Access to smokeless cooking fuel will improve women's quality of life by eliminating the consumption of biofuel and thereby providing a healthier cooking environment.

Machine learning reveals sex differences in clinical features of acute exacerbation of chronic obstructive pulmonary disease: A multicenter cross-sectional study

Introduction

Intrinsically, chronic obstructive pulmonary disease (COPD) is a highly heterogonous disease. Several sex differences in COPD, such as risk factors and prevalence, were identified. However, sex differences in clinical features of acute exacerbation chronic obstructive pulmonary disease (AECOPD) were not well explored. Machine learning showed a promising role in medical practice, including diagnosis prediction and classification. Then, sex differences in clinical manifestations of AECOPD were explored by machine learning approaches in this study.

Methods

In this cross-sectional study, 278 male patients and 81 female patients hospitalized with AECOPD were included. Baseline characteristics, clinical symptoms, and laboratory parameters were analyzed. The K-prototype algorithm was used to explore the degree of sex differences. Binary logistic regression, random forest, and XGBoost models were performed to identify sex-associated clinical manifestations in AECOPD. Nomogram and its associated curves were established to visualize and validate binary logistic regression.

Results

The predictive accuracy of sex was 83.930% using the k-prototype algorithm. Binary logistic regression revealed that eight variables were independently associated with sex in AECOPD, which was visualized by using a nomogram. The AUC of the ROC curve was 0.945. The DCA curve showed that the nomogram had more clinical benefits, with thresholds from 0.02 to 0.99. The top 15 sex-associated important variables were identified by random forest and XGBoost, respectively. Subsequently, seven clinical features, including smoking, biomass fuel exposure, GOLD stages, PaO2, serum potassium, serum calcium, and blood urea nitrogen (BUN), were concurrently identified by three models. However, CAD was not identified by machine learning models.

Conclusions

Overall, our results support that the clinical features differ markedly by sex in AECOPD. Male patients presented worse lung function and oxygenation, less biomass fuel exposure, more smoking, renal dysfunction, and hyperkalemia than female patients with AECOPD. Furthermore, our results also suggest that machine learning is a promising and powerful tool in clinical decision-making.

Biomass use and its health effects among the vulnerable and marginalized refugee families in the Gaza Strip

Introduction

Biomass fuel remains the most common type of fuel used in many developing countries, leading to indoor air pollution and serious health impacts.

Objective

The objective of this study was to compile evidence on the impact household fuel combustion has on child and adult health, with an emphasis on solid fuel use in Gaza.

Methods

In this cross-sectional study, 110 structured self-administered questionnaires were distributed in April 2019 among families living in the Al-Maghazi refugee camp.

Results

Participants reported that the main fuel used were wood, coal, cardboard, and a mix of wood, cardboard, and plastic, which were used for cooking, heating, baking, boiling water, and lighting. The most common symptoms were nasal irritation (71.8%), followed by headache (66.4%) and dizziness (65.4%). The results of logistic regression showed that the participants who used wood fuel had a higher chance of feeling eye irritation than those who used a mix of wood, cardboard, and dried grass (OR = 1.316; 95% CI = 1.54-8.99). The participants who opened windows during the burning process of biomass fuel were five times more likely to develop pneumonia than those who closed windows (OR = 5.53; 95%CI = 11.60-19.0).

Conclusion

there is an urgent need for community awareness campaigns designed to inform people about the risks of exposure to biomass fuel smoke and how to better implement household ventilation.

Prevalence of chronic obstructive pulmonary disease (COPD) among rural population: A national survey in Bangladesh

Background

In Bangladesh, there is a scarcity of nationally representative data on the burden of chronic obstructive pulmonary disease (COPD).

Methods

To estimate the COPD prevalence in rural settings, this cross-sectional, population-based study was conducted in all eight administrative divisions of Bangladesh, and involved adults aged 40 years and above. By using multi-stage random sampling, 2,458 individuals were enrolled. The Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines were used to diagnose COPD based on post-bronchodilator lung function, while additional participant data was gathered through computer-assisted personal interviews.

Results

A 2% COPD prevalence (95% CI: 1.45, 2.55) was found in the study sample with a statistically significant difference between males (2.7%; 95% CI: 1.8, 3.6) and females (1.2%; 95% CI: 0.59, 1.81). Increasing age significantly inflated the odds of having COPD irrespective of sex (OR: 1.03; 95% CI: 1.00, 1.05; P value < 0.05). Furthermore, prevalence of COPD was higher among manual workers, cigarette smokers, and those that used the indoor kitchen and did not have a primary education. Sex-based analysis showed that smokeless tobacco consumption was significantly associated with COPD occurrence among males (OR: 2.14; 95% CI: 1.05, 4.37; P value < 0.05), but not females. Further, using an indoor kitchen increased the odds of developing COPD by 400% among female participants (OR: 4.39; 95% CI: 1.37, 14.10; P value < 0.05).

Conclusion

This study provides a comprehensive sex-based estimation of COPD prevalence among rural population and imparts significant contribution to the growing database on COPD prevalence in Bangladesh.

Effects of indoor air pollution on tribal community in rural India and health risk assessment due to domestic biomass burning: a realistic approach using the lung deposition model

Indoor air pollution from the combustion of biomass fuel and associated health risks is a critical issue in developing countries. Concentrations of PM2.5 and PM10 are measured in Birbhum, West Bengal, during 2017-2018. PM2.5-bound elemental concentrations of twelve metals are determined in rural kitchens. The results showed higher toxicological risks in BMF (1.15) than the LPG users (0.14). The risk of non-carcinogenic exposure related with dermal contact and ingestion was observed in the acceptable limits (HQ < 1) for all age groups, and the risk associated with inhalation exposure from Cr, Ni, As, and Mn exceeded the acceptable limit. Results also suggest that carcinogenic risks from ingestion and dermal contact are within the acceptable limit (1 × 10-4-1 × 10-6) except Cr and As which were found to exceed the range. The deposition flux (Dφ) for multiple metals in the head airway region, tracheobronchial region, and alveolar regions was found to be higher in teenagers as compared to other groups, whereas the value was lower in infants. Further, it was notified from the Dφ that the metals could pass through the head airways and harm the tracheobronchial tree and alveolar region, increasing the risk of human health.

Chronic obstructive pulmonary disease (COPD) in women due to indoor biomass burning: a meta analysis

Chronic Obstructive Pulmonary Disease (COPD) is attributable to household air pollution and is known to increase the Disability Adjusted Life Years (DALYs), morbidity and mortality and women are most susceptible groups for the exposure. In order to understand the global risk among women with COPD due to exposure of household air pollutants, an evidence-based systematic review and meta-analysis was conducted. Meta regression analysis was carried out to identify potential sources of heterogeneity. The summary estimates of the included studies showed higher prevalence of COPD due to biomass fuel exposure in women. Clinical diagnosis has shown more risk of COPD prevalence compared to diagnosis based on spirometer test alone. However, the data between included studies for both clinical and spirometry-based studies showed higher heterogeneity. The present meta-data analysis has shown that household air pollutants may be a factor associated with increased risk of COPD in women.

Particulate matter exposure in biomass-burning homes of different communities of Brahmaputra Valley

Biomass burning for cooking prevalent in the developing countries is an issue which has been a concern for the past several decades for the noxious emissions and subsequent effects on the health of women and children due to the exposure of particulate matter (PM) and other gases. In this study, PM (PM₁, PM_2.5, and PM₁₀) were measured in biomass-burning households for different communities of Brahmaputra Valley region northeast India by a 31-channel aerosol spectrometer. The levels of emission of PM in the case of different community households were found to be significantly different. Also, the emission characteristics of different cooking time of the day were found to be different across communities. The emission levels in the biomass-burning households were compared with emission in household using "clean" LPG fuel, and it was found that the biomass fuels emitted 10-12 times more PM_2.5 and 6-7 times more PM₁₀. The number densities of the emission were found to be more with smaller sizes of particulates which could explain why such biomass-burning emissions can pose with greater health risks. The exposure doses were calculated and were found to be about three times higher in biomass-burning houses than "clean" LPG fuel. It is important to note that the exposure from biomass burning while cooking has a gender perspective. The woman of the house generally takes care of the activities in the kitchen and get exposed to the noxious PM and the gases. Children often accompany their mothers and face the same fate.

Prevalence of chronic obstructive pulmonary disease in India: A systematic review and meta-analysis

Background and Objective:

The prevalence of chronic obstructive pulmonary disease (COPD) is increasing worldwide. There is a lack of national-level estimates on the magnitude of COPD in India. Hence, we estimated the prevalence of COPD among adults in India.

Methods:

We searched PubMed, Embase, Cochrane Library, Google Scholar, and Scopus and included community-based cross-sectional studies reporting data on the prevalence of COPD among adults based on spirometry. A random-effects model was used to estimate the pooled prevalence of COPD.

Results:

In the eight identified studies, (pooled sample of 8,569 individuals), the estimated prevalence was 7.4% (95% confidence interval: 5.0%–9.8%), I² = 95.4% (P < 0.001). The prevalence was higher among males, in the urban area, and the northern region.

Conclusion:

Adequate training and resources should be provided to diagnose COPD at primary health care level for early management. A nationwide population-based survey is indicated to provide reliable estimates of the burden to inform evidence-based community-based interventions.

Prevalence of COPD among population above 30 years in India: A systematic review and meta-analysis

Background

By 2030, Sustainable Development Goal 3.4 aims to reduce the premature mortality caused by non-communicable diseases through prevention and treatment. Chronic obstructive pulmonary disease is the second leading cause of mortality and disability-adjusted life years in India. This review was conducted to estimate the prevalence of COPD using systematic review and meta-analysis technique.

Method

Search was conducted using six databases for studies on COPD among population above 30 years in India between years 2000 to 2020. Cross-sectional and cohort studies reporting prevalence of COPD and associated risk factors were included in the present review. Screening and data extraction was done by two authors independently. Studies were appraised for quality using the modified New Castle Ottawa scale and reporting quality was assessed using STROBE guidelines.

Result

Our search returned 8973 records, from which 23 records fulfilled the eligibility criteria. Overall, the prevalence of COPD among population aged 30 years and above in India was 7%. Risk factors like active and passive smoking, biomass fuel exposure, environmental tobacco smoke, occupational exposure to dust, indoor and outdoor pollution, and increasing age were reported to have a significant association with COPD among Indian population.

Conclusion

Our findings suggest the need for a multicentric national-level research study to understand COPD burden and its contributing risk factors. The findings also suggest the need for COPD sensitive health literacy program focused on early screening and primary prevention of risk factors for COPD, which may help early initiation of self-management practices, that are crucial for better quality of life.

Effect of Indoor Air Pollution on Chronic Obstructive Pulmonary Disease (COPD) Deaths in Southern Asia-A Systematic Review and Meta-Analysis

BACKGROUND

About half of the population in developing countries are exposed to indoor pollution such as combustion fuels at present. Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality globally and the primary cause of COPD in women is indoor air pollution exposure, while tobacco smoking is the leading cause in men. The aim of this systematic review and meta-analysis is to evaluate the correlation between the indoor air pollution and deaths related to COPD and COPD prevalence in South Asia.

METHODS

A systematic search on studies with sufficient statistical power has been conducted from 1985 until 30 June 2020, in English electronic databases following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in MEDLINE and PubMed databases with the terms Chronic Obstructive Pulmonary disease COPD or Chronic Bronchitis or Emphysema or COPD Deaths or Chronic Obstructive Lung Disease or Airflow Obstruction or Chronic Airflow Obstruction or Airflow Obstruction, Chronic or Bronchitis, Chronic and Mortality or Death or Deceased was conducted. Studies were eligible if they were Prospective controlled or non-controlled trials conducted in Southern Asia/ Asia and Retrospective studies conducted in Southern Asia/ Asia.

RESULTS

The results have concluded that long term exposure to indoor pollution had a significant effect on COPD deaths as well as its symptoms. Odd's ratio was in a range of 1.05 (Randomized controlled trials) to 7.87 (Cross sectional studies) for all the studies mentioned. Meta-analysis observed a significantly higher Odds Ratio of 2.13 for COPD mortality and 2.08 for COPD prevalence on exposure to indoor air pollution.

CONCLUSION

Exposure to solid fuel smoke is consistently and significantly correlated with COPD mortality and COPD prevalence in South Asian countries, in spite of heterogeneity observed in the studies included. For performing domestic tasks, initiatives are to be taken to reduce dependency on solid fuel by using cleaner alternatives or comparatively cleaner technology.

FEV1/FEV6 is effective as a surrogate for FEV1/FVC in the diagnosis of chronic obstructive pulmonary disease

BACKGROUND AND OBJECTIVE

Chronic Obstructive Pulmonary Disease (COPD) causes substantial morbidity and mortality across the globe. Diagnosis of COPD requires post-bronchodilator FEV1/FVC <0.70 as per GOLD Guidelines. FVC maneuver requires a minimum of 6 seconds of forceful expiration with no flow for 1 second for an accepted effort, which lacks any fixed cut-off point. This leads to discomfort, especially in advanced COPD and old aged population. We conducted this study to find the utility of FEV1/FEV6 as a surrogate for FEV1/FVC, the correlation between the two ratios, and the fixed cut-off value of FEV1/FEV6 for COPD diagnosis.

METHODS

This was a prospective, cross-sectional study approved by the institutional ethics committee conducted from January 2017 to November 2018. Consented patients above 18 years suspected of COPD underwent Spirometry as per ATS guidelines. FEV1, FEV6, FEV1/FEV6 and FEV1/FVC ratios were recorded from the best acceptable maneuver.

RESULTS

Out of 560 screened patients, 122 diagnosed as COPD. The correlation coefficient between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio was 0.972 (p < 0.01). The relationship between the post-bronchodilator FEV1/FVC ratio and FEV1/FEV6 ratio (linear regression analysis) was found out as: FEV1/FVC = -1.845 + 1.009(FEV1/FEV6). Using this formula, the post-bronchodilator FEV1/FEV6 value of 71.845 was obtained corresponding to the post-bronchodilator FEV1/FVC value of 70.00.

CONCLUSION

We found a positive correlation coefficient (r = 0.972, p < 0.001) between the FEV1/FEV6 and FEV1/FVC ratios and the cut off value of 71.845 (p < 0.01) for the post-bronchodilator FEV1/FEV6 ratio for the diagnosis of COPD. Thus FEV1/FEV6 should be used as a surrogate for FEV1/FVC for the diagnosis of COPD.

COPD in Biomass exposed nonsmokers: a different phenotype

INTRODUCTION

Chronic obstructive pulmonary disease, most commonly caused by tobacco smoking, is increasingly reported in nonsmoking patients exposed to domestic combustion of biomass fuels. This is particularly common among rural women in the low- and middle-income countries. It is highly likely that the disease in these patients is a different clinical phenotype.

AREAS COVERED

This manuscript covers epidemiological and clinical aspects of biomass-exposed COPD and also dwells upon its different phenotypic characteristics.

EXPERT OPINION

Chronic obstructive pulmonary disease in biomass-exposed, nonsmoker patients which predominantly presents with features of chronic bronchitis is more likely a distinct phenotype with greater likelihood of small airway involvement.

Assessment of the effectiveness of a pharmacist approach for improving disease-specific knowledge and treatment in patients with chronic obstructive pulmonary disease

OBJECTIVE

Adequate knowledge is essential for the appropriate management of chronic conditions such as chronic obstructive pulmonary disease (COPD). However, some patients may not be able either to comprehend or obtain adequate information. This study aims to assess the effectiveness of the clinical pharmacist approach to refining disease-specific knowledge in patients with COPD treated in a tertiary care hospital.

METHODS

A prospective observational longitudinal study was carried out in adult COPD patients for 9 months in the tertiary care hospital of Pune. At the time of enrolment, disease-specific knowledge of patients with COPD was assessed using the Bristol COPD Knowledge Questionnaire (BCKQ). After the assessment, patients were educated, counselled verbally and provided with a validated COPD information leaflet. The patients' knowledge was reassessed 1 month and 3 months after enrolment. Pre and post scores of BCKQ were compared by ANOVA followed by Tukey's post hoc test. The difference in the proportions was calculated using the χ² test.

RESULTS

Of 75 patients, the majority were men (53.33%), aged >60 years (72%), employed (62.67%) and had obtained secondary education (37.33%). The mean baseline BCKQ overall score of the patients was 25.87, which increased after education to 42.43 on the first visit (1 month) and to 45.62 on the second visit (3 months) (p<0.0001). At baseline, the topics 'vaccination', 'inhaled steroids' and 'antibiotics' returned the lowest mean scores of 0.37, 0.38 and 0.60, which were increased to 2.30, 2.70 and 2.72, respectively, after follow-up.

CONCLUSION

The knowledge of patients with COPD about the disease and its treatment was poor at the time of enrolment. Proper counselling and education provided by the clinical pharmacist helped to improve the patients' knowledge about COPD and its treatment.

Household air pollution in India and respiratory diseases: current status and future directions

PURPOSE OF REVIEW

Combustion of solid cooking fuels employed by more than 3 billion people globally, contributes to approximately one third of ambient air pollution. In the recent past, the issue has drawn global attention because of its threat to the health of rural communities, particularly women and children. This review is focused on the evidence from India on effects of household air pollution (HAP) on respiratory health and interventions to replace the solid fuels.

RECENT FINDINGS

HAP exposure is a major risk factor for increased respiratory symptoms, respiratory infections, and chronic obstructive pulmonary disease. In most studies, the odds ratio for the risk of development of respiratory disorders is more than one in HAP exposed individuals. HAP is also associated with increased risk of tuberculosis, asthma, mortality from cardio-respiratory illnesses, and nonrespiratory problems such as adverse pregnancy outcomes, prematurity, and low birth weight.

SUMMARY

Household air pollution is a common but preventable risk factor for respiratory diseases. Replacement of solid cooking fuels with clean fuels such as LPG gas as exemplified by the 'Ujjwala' program of India is likely to be most effective intervention to reduce the HAP related disease burden.

Household cooking fuel use and its health effects among rural women in southern India-A cross-sectional study

The use of biomass fuel is associated with the deterioration of human health and women are more likely to develop health conditions due to their exposure to indoor air pollution during cooking. This study was conducted to assess the pattern of fuel used for cooking in households as well as to determine the association between the types of fuel used with respect to socio-demographic characteristics and health status of women. A community based cross-sectional survey was conducted between August 2016 and September 2018 in four rural areas and one semi-urban area of Udupi district, Karnataka, India. The study comprised 587 families including 632 women. A pre-tested semi-structured questionnaire was used to collect data on the type of fuel as well as self-reported health conditions. Overall, 72.5% of the families used biomass, where 67.2% families were currently using both biomass and liquefied petroleum gas while only biomass was used in 5.3% of the families for cooking. Among women, being ever exposed to biomass fuel was significantly associated with their age, literacy level, occupation and socio-economic status (p < 0.001). Those who were exposed to biomass fuel showed a significant association with self-reported ophthalmic (AOR = 3.85; 95% CI: 1.79–8.29), respiratory (OR = 5.04; 95% CI: 2.52–10.07), cardiovascular (OR = 6.07; 95% CI: 1.88–19.67), dermatological symptoms /conditions (AOR = 3.67; 95% CI: 1.07–12.55) and history of adverse obstetric outcomes (AOR = 2.45; 95% CI: 1.08–5.57). A positive trend was observed between cumulative exposure to biomass in hour-years and various self-reported health symptoms/conditions (p < 0.001). It was observed that more than two-thirds of women using biomass fuel for cooking were positively associated with self-reported health symptoms. Further longitudinal studies are essential to determine the level of harmful air pollutants in household environment and its association with various health conditions among women in this region.

Risk of COPD due to indoor air pollution from biomass cooking fuel: a systematic review and meta-analysis

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of mortality in developing nations. In this meta-analysis, we aimed to determine the association between indoor air pollution and risk of COPD. Database searches were conducted using indoor air pollution, biomass and COPD related terms to identify relevant articles. The eligible studies were case-control, retrospective cohort, cross-sectional studies and conducted in adults that assessed COPD using any diagnostic criteria. A total of 35 studies with 73,122 participants were included. The pooled analysis showed that exposure to indoor air pollution due to solid biomass fuels increased risk of COPD by 2.65 (95% confidence interval [CI] 2.13-3.31; n = 73,122) and chronic bronchitis by 2.89 (95% CI 2.18-3.82) times more compared to non-biomass fuels. The risk of COPD was higher in Africa region (odds ratio [OR] 3.19), Asia (OR 2.88), South America (OR 2.15), Europe (OR 2.30) and North America (OR 2.14). The results of our meta-analysis indicated that exposure to indoor air pollution due to biomass smoke is strongly associated with COPD.Abbreviations: CS: cross-sectional; CC: case-control; NR: not reported; ATS: American Thoracic Society; BMRC: British Medical Research Council; GOLD: Global Initiative for Obstructive Lung Disease; IAP: indoor air pollution; BMF: biomass fuel; CB: chronic bronchitis; OR: odds ratio; UCI; upper confidence interval; LCI: lower confidence interval; COPD: chronic obstructive pulmonary disease.

Measuring the impact of household energy consumption on respiratory diseases in India

Background

Most households in developing countries like India are not able to afford to get the services of efficient energy for cooking and lighting. Therefore, they rely mostly on solid fuels (firewood, dung cakes, crop residue, coal/coke/lignite). Such fuels cause respiratory diseases like tuberculosis, asthma respiratory cancer. Hence, this study aims to estimate the association between different types of energy used and the prevalence of respiratory diseases in India where more than 50% of the population relies on solid fuels for cooking.

Methods

The study is based on 117,752 respondents who were diagnosed with various chronic diseases such as diabetes, chronic heart diseases, leprosy, chronic renal diseases, tuberculosis, asthma etc. from District Level Household Survey (DLHS-4) which was conducted in 2012–13. Individuals who were diagnosed with a chronic illness after a proper medical examination have been considered as a dependent variable. Exposure to the type of cooking fuel is the main exposure variable, which recognises the dependence on energy. Logistic regression has been utilized to understand the association between the use of solid fuels for cooking and the prevalence of respiratory diseases.

Results

The dependence on solid fuels is very high in rural areas (72.22%) as compared to urban areas (21.43%). Among different castes, the reliance on solid fuels for cooking is highest among Scheduled Castes (61.79%) and Scheduled Tribes (70.46%). Individuals living in households where crop residue and coal/lignite is used for cooking suffer from asthma/chronic respiratory failure in the higher proportion as compared to others. Results further revealed that the use of solid fuels for cooking has a strong association with respiratory diseases. Individuals living in households where solid fuels like firewood [OR: 1.27 (0.001); C.I.: 1.19–1.35], crop residue [OR: 1.33 (0.001); C.I.:1.19–1.48], and coal [OR: 1.60 (0.001); C.I.:1.32–1.93] are used as primary fuel for cooking are 17 to 60% more likely to suffer from respiratory diseases.

Conclusion

Use of solid fuels is associated with respiratory diseases like asthma, tuberculosis and cancer of the respiratory system. Assuming these associations are causal, therefore, about 17 to 60% of the respiratory diseases in India could be prevented by providing access to clean cooking fuel to the individuals.

Under- and over-diagnosis of COPD: a global perspective

Globally, chronic obstructive pulmonary disease (COPD) is the fourth major cause of mortality and morbidity and projected to rise to third within a decade as our efforts to prevent, identify, diagnose and treat patients at a global population level have been insufficient. The European Respiratory Society and American Thoracic Society, along with the Global Initiative for Chronic Obstructive Lung Disease (GOLD) strategy document, have highlighted key pathological risk factors and suggested clinical treatment strategies in order to reduce the mortality and morbidity associated with COPD. This review focuses solely on issues related to the under- and over-diagnosis of COPD across the main geographical regions of the world and highlights some of the associated risk factors. Prevalence of COPD obtained mainly from epidemiological studies varies greatly depending on the clinical and spirometric criteria used to diagnose COPD, i.e. forced expiratory volume in 1 s to forced vital capacity ratio <0.7 or 5% below the lower limit of normal, and this subsequently affects the rates of under- and over-diagnosis. Although under-utilisation of spirometry is the major reason, additional factors such as exposure to airborne pollutants, educational level, age of patients and language barriers have been widely identified as other potential risk factors. Co-existent diseases, such as asthma, bronchiectasis, heart failure and previously treated tuberculosis, are reported to be the other determinants of under- and over-diagnosis of COPD.

COPD is a major cause of morbidity and mortality, but misdiagnosis of COPD is a huge problem worldwide. Its main causes are under-utilisation of spirometry and lack of uniformity in diagnosis criteria, particularly in resource poor settings.http://ow.ly/KfP330nonkh

Chronic bronchitis and airflow obstruction is associated with household cooking fuel use among never-smoking women: a community-based cross-sectional study in Odisha, India

BACKGROUND

The use of solid biomass as cooking fuel could be a potential risk factor for chronic bronchitis (CB) and airflow obstruction (AFO) among never-smoking women. The disease burden in India among women is generally underestimated due to limited population-based epidemiological investigations. The aim of the study was to determine the prevalence of CB and AFO among never-smoking women, and its association with household cooking fuel use.

METHODS

We conducted a community-based cross-sectional study with a representative study sample (N = 1120) in Odisha, India during 2013-14. Study participants, never-smoking women aged 18-49 years, were recruited randomly from the population census. Trained community health volunteers administered a validated questionnaire that aligned with the standards of the Burden of Obstructive Lung Disease (BOLD) initiative and conducted spirometry. Prevalence estimates of CB (defined as "cough with productive of sputum for at least 3 months of the year for at least 2 years") and AFO (pre-bronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) < 0.7) was estimated. Indoor PM2.5 exposure data were collected from a subset of 130 of the total 1120 homes in the study settings. Multivariable regression models were used to estimate the associated risk factors.

RESULTS

Prevalence of CB and AFO were 7.3 and 22.4% respectively among the study participants. Of the study participants, 31% used exclusive liquefied petroleum gas, 18% used mixed fuel and 51% exclusively used solid biomass fuel for household cooking. In adjusted analysis, both CB (odds ratio 1·96, 95% CI: 1.06-3.64; p = 0·031) and AFO (OR 5.55, 95% CI: 3.51-8.78; p < 0·001) were found to be associated with cooking with solid biomass fuel. Interquartile range increases in PM2.5 was associated with significantly lower FEV1/FVC ratio.

CONCLUSIONS

The study highlights that the estimates of population burden of CB and AFO are much higher than shown in previous epidemiological studies, and that cooking fuel type and time spent on cooking were associated with increased chronic bronchitis as well as decreased lung function as measured by FEV1/FCV ratios. To most accurately understand the current burden of disease and most effectively prevent an escalation in the future disease burden, further epidemiological investigations are warranted.

Chronic obstructive pulmonary disease associated with biomass fuel use in women: a systematic review and meta-analysis

Introduction

Chronic obstructive pulmonary disease (COPD) is a major and growing cause of morbidity and mortality worldwide. The global prevalence of COPD is growing faster in women than in men. Women are often exposed to indoor pollutants produced by biomass fuels burning during household activities.

Methods

We conducted a meta-analysis to establish the association between COPD and exposure to biomass smoke in women.Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we searched MEDLINE and Scopus databases in 31December 2016, with the terms: "wood", "charcoal", "biomass", "solid fuels", "organic fuel", "biofuel", "female", "women", "COPD", "chronic bronchitis", "emphysema", "chronic obstructive pulmonary disease". Studies were eligible if they were case-control or cross-sectional studies involving exposure to indoor biomass smoke, conducted at any time and in any geographic location. Fixed-effects or random-effects meta-analysis was used to generate pooled OR.

Results

24 studies were included: 5 case-control studies and 19 cross-sectional studies. Biomass-exposed individuals were 1.38 times more likely to be diagnosed with COPD than non-exposed (OR 1.38, 95% CI 1.28 to 1.57).Spirometry-diagnosed COPD studies failed to show a significant association (OR 1.20, 95% CI 0.99 to 1.40). Nevertheless, the summary estimate of OR for chronic bronchitis (CB) was significant (OR 2.11, 95% CI 1.70 to 2.52). The pooled OR for cross-sectional studies and case-control studies were respectively 1.82 (95% CI 1.54 to 2.10) and 1.05 (95% CI 0.81 to 1.30). Significant association was found between COPD and biomass smoke exposure for women living as well in rural as in urban areas.

Conclusions

This study showed that biomass smoke exposure is associated with COPD in rural and urban women.In many developing countries, modern fuels are more and more used alongside traditional ones, mainly in urban area. Data are needed to further explore the benefit of the use of mixed fuels for cooking on respiratory health, particularly on COPD reduction.

Air pollution and environmental risk factors for altered lung function among adult women of an urban slum area of Delhi: A prevalence study

Background:

Household and ambient air pollution are jointly responsible for about 7 million premature deaths annually. Women living in slums, with unhealthy environment, both indoors and outdoors, particularly those living close to industrial and/or vehicular pollution zones due to multiple sources of air pollution, are at the higher risk of having impaired lung function tests.

Objective:

The aim of this study was to estimate the prevalence of abnormal lung functions and to identify the environmental risk factors associated with them among adult women of 18–59 years.

Materials and Methods:

A total of 550 women aged 18–59 years were approached in a representative urban slum. Five hundred consented to participate and 299 had prebronchodilator spirometry satisfying ATS standards. House visits to assess environmental conditions were conducted to determine their association with forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC). Chi-square test was used to test the association of risk factors with lung functions. ANOVA was used to test the association of mean values of FEV1 and FVC with age.

Results:

Out of 299 participants with acceptable spirometric curves, 5% had reduced FEV1/FVC ratio than the normal and 26.8% and 17.4% had lower values than predicted for FVC and FEV1, respectively. Altered lung function was related to age, tobacco smoking, and history of respiratory disease.

Conclusions:

Both ambient and household air pollution have a deleterious pulmonary effect on long-term women residents of a representative urban slum in Delhi.

PM2.5 pollution from household solid fuel burning practices in central India: 1. Impact on indoor air quality and associated health risks

PM_2.5 concentrations were measured in residential indoor environment in slums of central India during 2012-2013. In addition, a suite of chemical components including metals (Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Cd, Pb, Mo, Se, Sb, Na, Mg, K and Hg), ions (Na⁺, Mg²⁺, K⁺, Ca²⁺, F^-, Cl^-, NH₄⁺, NO₃^- and SO₄^2-) and carbon (OC and EC) were analyzed for all samples. Indoor PM_2.5 concentrations were found to be several folds higher than the 24-h national ambient air quality standard (60 µg/m³) for PM_2.5 in India, and the concentrations were found to vary from season to season. Mass closure was attempted for PM_2.5 data, and close to 100 % mass was accounted for by organic matter, crustal material, secondary organic and inorganic aerosols and elemental carbon. Additionally, carcinogenic and non-carcinogenic health risks associated with exposure to indoor PM_2.5 (inhalation, dermal and ingestion) were estimated and while exposures associated with dermal contact and ingestion were found to be within the acceptable limits, risk associated with inhalation exposure was found to be high for children and adults. Elements including Al, Cd, Co, Cr, Mn, Ni, As and Pb were present in high concentrations and contributed to carcinogenic and non-carcinogenic risks for residents' health. Results from this study highlight the need for efforts to reduce air pollution exposure in slum areas.

Biomass smoke exposure as an occupational risk: cross-sectional study of respiratory health of women working as street cooks in Nigeria

OBJECTIVE

Little is known about respiratory health of women who are occupationally exposed to biomass smoke outside their homes. This study reports the exposure and respiratory health of street cooks in Ile-Ife, Nigeria.

METHODS

We assessed exposure to biomass smoke by questionnaire in 188 street cooks and 197 control women and by personal diffusive samplers to quantify volatile organic compounds (VOCs) in a subsample of the women. Respiratory symptoms were assessed by a standardised questionnaire, and pulmonary function was assessed by spirometry before and after bronchodilation. Regression analysis was conducted to compare the outcome between the two groups.

RESULTS

The study included 188 women (median age 40, IQR 30-50 years) who had worked as street cooks for a median of 7 years (IQR 3-15 years) and 197 control women with similar demographics. Benzene concentration in passive samplers worn by the street cooks was significantly higher compared with controls (median (IQR) 119.3 (82.7-343.7) µg/m³ vs 0.0 (0.0-51.2) µg/m³, p<0.001). The odds of reported respiratory symptoms were significantly higher among the street cooks than controls: cough (adjusted OR 4.4, 95% CI 2.2 to 8.5) and phlegm (adjusted OR 3.9, 95% CI 1.5 to 7.3). The street cooks also had higher odd of airway obstruction as measured by forced expiratory volume in 1 s/forced vital capacity <0.7: 11% 3% (adjusted OR of 3.3 (95% CI 1.3 to 8.7)).

CONCLUSIONS

This study provides evidence of adverse respiratory effects among street cooks using biomass fuels.

A cross-sectional study on prevalence of chronic obstructive pulmonary disease (COPD) in India: rationale and methods

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common preventable and treatable chronic respiratory disease, which affects 210 million people globally. Global and national guidelines exist for the management of COPD. Although evidence-based, they are inadequate to address the phenotypic and genotypic heterogeneity in India. Co-existence of other chronic respiratory diseases can adversely influence the prognosis of COPD.India has a huge burden of COPD with various risk factors and comorbid conditions. However, valid prevalence estimates employing spirometry as the diagnostic tool and data on important comorbid conditions are not available. This study protocol is designed to address this knowledge gap and eventually to build a database to undertake long-term cohort studies to describe the phenotypic and genotypic heterogeneity among COPD patients in India.

OBJECTIVES

The primary objective is to estimate the prevalence of COPD among adults aged ≥25 years for each gender in India. The secondary objective is to identify the risk factors for COPD and important comorbid conditions such as asthma and post-tuberculosis sequelae. It is also proposed to validate the currently available definitions for COPD diagnosis in India.

METHODS AND ANALYSIS

A cross-sectional study will be undertaken among the populations of sub-urban areas of Chennai and Shillong cities, which represent the Southern and Northeastern regions of India. We will collect data on sociodemographic variables, economic characteristics, risk factors of COPD and comorbidities. The Global Initiative for Obstructive Lung Disease (GOLD) and Global Initiative for Asthma (GINA) definitions will be used for the diagnosis of COPD and asthma. Data will be analysed for estimation of the prevalence of COPD, asthma and associated factors.

ETHICS AND DISSEMINATION

This study proposal was approved by the respective institutional ethics committees of participating institutions. The results will be disseminated through publications in the peer-reviewed journals and a report will be submitted to the concerned public health authorities in India for developing appropriate research and management policies.

Household air pollution from various types of rural kitchens and its exposure assessment

Exposure to household air pollutants has become a leading environmental health risk in developing countries. Considering this, real-time temporal variation in fine particulate matter (PM_2.5) and carbon monoxide (CO) concentrations were measured in various types of rural household kitchens. Observed average concentrations of PM_2.5, CO, percent relative humidity (%RH) and temperature (T) in five different kitchen types were 549.6μg/m³, 4.2ppm, 70.2% and 20°C respectively. Highest CO and PM_2.5 concentration were found in household performing cooking in indoor kitchens (CO: 9.3ppm; PM_2.5: 696.5μg/m³) followed by outdoor kitchens (CO: 5.8ppm; PM_2.5: 539.5μg/m³). The concentration of PM_2.5 and CO varied according to the fuel type and highest concentration was observed in kitchens using cowdung cakes followed by agricultural residue>firewood>biogas>Liquefied Petroleum Gas (LPG). Results revealed that the pollutants concentration varied with kitchen type, fuel type and the location of kitchen. An exposure index was developed to calculate the exposure of cook, non-cook and children below 5years. Analysis of exposure index values shows that cooks, who use solid biomass fuel (SBF) in indoor kitchen, are four times more exposed to the harmful pollutants than the cooks using clean fuel. Further, using indoor PM_2.5 concentrations, hazard quotient was calculated based on evaluation of intake concentration and toxicological risk, which also shows that SBF users have higher health risks (hazard quotient>1) than the clean fuel (LPG) users.

Biomass smoke exposure and chronic lung disease

PURPOSE OF REVIEW

Approximately 3 billion people worldwide rely on coal and biomass fuel for cooking and heating. Biomass smoke exposure is associated with several chronic lung diseases, including chronic obstructive pulmonary disease (COPD), asthma-COPD overlap syndrome, usual interstitial pneumonitis, hut lung, and bronchial anthracofibrosis. Household air pollution primarily from biomass smoke is the biggest risk factor for COPD worldwide. Despite the significant burden of biomass smoke-related respiratory disease, the exposure is still underappreciated worldwide, especially in high-income countries.

RECENT FINDINGS

Recent literature highlights the immunoinflammatory differences between biomass smoke-related COPD and tobacco smoke-related COPD that may lead to better understanding of the differences in the clinical phenotypes between the two entities, suggests an association with the recently recognized asthma-COPD overlap syndrome, and elucidates the burden of disease in high-income countries.

SUMMARY

The current review focuses on the association between biomass smoke and common chronic respiratory diseases, discuss differences between biomass smoke-related COPD and tobacco smoke-related COPD, highlights chronic respiratory diseases that are specific for biomass smoke exposure such as hut lung and bronchial anthracofibrosis, and discusses the known impact of beneficial interventions.

Global and regional estimates of COPD prevalence: Systematic review and meta-analysis

Background

The burden of chronic obstructive pulmonary disease (COPD) across many world regions is high. We aim to estimate COPD prevalence and number of disease cases for the years 1990 and 2010 across world regions based on the best available evidence in publicly accessible scientific databases.

Methods

We conducted a systematic search of Medline, EMBASE and Global Health for original, population–based studies providing spirometry–based prevalence rates of COPD across the world from January 1990 to December 2014. Random effects meta–analysis was conducted on extracted crude prevalence rates of COPD, with overall summaries of the meta–estimates (and confidence intervals) reported separately for World Health Organization (WHO) regions, the World Bank's income categories and settings (urban and rural). We developed a meta–regression epidemiological model that we used to estimate the prevalence of COPD in people aged 30 years or more.

Findings

Our search returned 37 472 publications. A total of 123 studies based on a spirometry–defined prevalence were retained for the review. From the meta–regression epidemiological model, we estimated about 227.3 million COPD cases in the year 1990 among people aged 30 years or more, corresponding to a global prevalence of 10.7% (95% confidence interval (CI) 7.3%–14.0%) in this age group. The number of COPD cases increased to 384 million in 2010, with a global prevalence of 11.7% (8.4%–15.0%). This increase of 68.9% was mainly driven by global demographic changes. Across WHO regions, the highest prevalence was estimated in the Americas (13.3% in 1990 and 15.2% in 2010), and the lowest in South East Asia (7.9% in 1990 and 9.7% in 2010). The percentage increase in COPD cases between 1990 and 2010 was the highest in the Eastern Mediterranean region (118.7%), followed by the African region (102.1%), while the European region recorded the lowest increase (22.5%). In 1990, we estimated about 120.9 million COPD cases among urban dwellers (prevalence of 13.2%) and 106.3 million cases among rural dwellers (prevalence of 8.8%). In 2010, there were more than 230 million COPD cases among urban dwellers (prevalence of 13.6%) and 153.7 million among rural dwellers (prevalence of 9.7%). The overall prevalence in men aged 30 years or more was 14.3% (95% CI 13.3%–15.3%) compared to 7.6% (95% CI 7.0%–8.2%) in women.

Conclusions

Our findings suggest a high and growing prevalence of COPD, both globally and regionally. There is a paucity of studies in Africa, South East Asia and the Eastern Mediterranean region. There is a need for governments, policy makers and international organizations to consider strengthening collaborations to address COPD globally.

Impact of air quality guidelines on COPD sufferers

Background

COPD is one of the leading causes of morbidity and mortality in both high- and low-income countries and a major public health burden worldwide. While cigarette smoking remains the main cause of COPD, outdoor and indoor air pollution are important risk factors to its etiology. Although studies over the last 30 years helped reduce the values, it is not very clear if the current air quality guidelines are adequately protective for COPD sufferers.

Objective

This systematic review was to summarize the up-to-date literature on the impact of air pollution on the COPD sufferers.

Methods

PubMed and Google Scholar were utilized to search for articles related to our study’s focus. Search terms included “COPD exacerbation”, “air pollution”, “air quality guidelines”, “air quality standards”, “COPD morbidity and mortality”, “chronic bronchitis”, and “air pollution control” separately and in combination. We focused on articles from 1990 to 2015. We also used articles prior to 1990 if they contained relevant information. We focused on articles written in English or with an English abstract. We also used the articles in the reference lists of the identified articles.

Results

Both short-term and long-term exposures to outdoor air pollution around the world are associated with the mortality and morbidity of COPD sufferers even at levels below the current air quality guidelines. Biomass cooking in low-income countries was clearly associated with COPD morbidity in adult nonsmoking females.

Conclusion

There is a need to continue to improve the air quality guidelines. A range of intervention measures could be selected at different levels based on countries’ socioeconomic conditions to reduce the air pollution exposure and COPD burden.

Prevalence of obstructive lung disease in an African country using definitions from different international guidelines: a community based cross-sectional survey

BACKGROUND

Obstructive lung disease (OLD), a major global public health problem, has been less investigated in African countries. We assessed the prevalence and determinants of OLD in Yaounde (the capital city of Cameroon), using internationally agreed definitions.

METHODS

Participants were adults (age >19 years) screened during a community-based survey between December 2013 and April 2014. Air flow limitation (AFL) was based on a pre-bronchodilator forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) below the lower limit of normal (LLN, AFL-LLN). Chronic obstructive pulmonary disease (COPD) was based on post-bronchodilator FEV1/FVC ratio < LLN (COPD-LLN).

RESULTS

Of the 1287 subjects included, 51.9% were female, 9.3% were current smokers and their mean age was 34.4 ± 12.8 years. Forty-nine (3.8%, 95% CI 2.8-4.9%) participants had AFL-LLN. Thirty-one subjects had COPD-LLN; giving a prevalence of COPD-LLN of (2.4%, 95% CI 1.6-3.3%). In multivariable analysis, male gender (AOR 2.42; 95% CI 1.12-5.20) and lifetime wheezing (AOR 2.88; 95% CI 1.06-7.81) were the determinants of COPD-LLN. Otherwise, male sex (AOR 1.93, 95% CI 1.00-3.73), age 40-59 years (AOR 1.99, 95% CI 1.04-3.81) and lifetime wheezing (AOR 2.65, 95% CI 1.13-6.20) remained as independent determinants of AFL-LLN.

CONCLUSIONS

Obstructive lung disease based on more accurate definitions was relatively infrequent in this population. It is important to sensitize the medical staff and the general public about this condition which should be actively investigated in individuals aged 40 years and above.

Pollutional haze and COPD: etiology, epidemiology, pathogenesis, pathology, biological markers and therapy

In recent years, serious pollutional haze occurs in the mainland of China thanks to the development of urbanization and industrialization. There is a close relationship between air pollution and the occurrence and development of chronic obstructive pulmonary disease (COPD), but there are some new characteristics in some aspects of COPD associated with pollutional haze compared with COPD induced by traditional physical and chemical factors. This article attempts to summarize the new progress from these new features of COPD related to pollutional haze, focus on etiology, epidemiology, pathogenesis, pathology, biological markers and therapy.

Predictors of outcome in patients admitted with acute exacerbation of chronic obstructive pulmonary disease in a rural Tertiary Care Center

Background:

Chronic obstructive pulmonary disease (COPD) is associated with a high degree of mortality and morbidity around the world with the burden of the disease being more in the developing countries. In the Indian context data is limited. This study was carried out to determine the predictors of outcome in patients admitted with acute exacerbation of COPD in a rural Tertiary Care Center in the state of Kerala.

Materials and Methods:

This was a prospective cohort study. Patients admitted with acute exacerbation of COPD in the Intensive Care Unit between August 2013 and July 2014 was included in the study. Sociodemographic data, clinical variables, and investigations were collected. Mortality with respect to relevant risk factors was compared using Kaplan–Meier method and Cox proportional hazard model.

Results:

Seventy patients were enrolled in the study of whom 58 (82.9%) were above the age of 60 years. Majority of the patients (87.1%) were males. Tobacco smoking was the main risk factor in them. All the females had a history of exposure to biomass fuel in the form of firewood; none of them were smokers. Majority of patients (80.0%) had a history of one or more co-existing illnesses. Anemia was found to be an independent risk factor for mortality (adjusted hazard ratio: 3.167, 95% confidence interval: 1.516–6.616). Risk factors for poor outcome in COPD patients reported from other centers in India were not found to be relevant in this study.

Conclusions:

Anemia could be an independent risk factor for mortality in COPD patients. India already has a high prevalence of iron deficiency anemia especially in the rural area and in the geriatric population. Henceforth, family practitioners and primary care physicians may remain vigilant regarding the development of anemia in their COPD patients and institute remedial measures without delay. Futhermore, the wide variation reported in the predictors of outcome of COPD along with the finding of this study calls for an urgent need for more studies.

Global and regional estimates of COPD prevalence: Systematic review and meta-analysis

BACKGROUND

The burden of chronic obstructive pulmonary disease (COPD) across many world regions is high. We aim to estimate COPD prevalence and number of disease cases for the years 1990 and 2010 across world regions based on the best available evidence in publicly accessible scientific databases.

METHODS

We conducted a systematic search of Medline, EMBASE and Global Health for original, population-based studies providing spirometry-based prevalence rates of COPD across the world from January 1990 to December 2014. Random effects meta-analysis was conducted on extracted crude prevalence rates of COPD, with overall summaries of the meta-estimates (and confidence intervals) reported separately for World Health Organization (WHO) regions, the World Bank's income categories and settings (urban and rural). We developed a meta-regression epidemiological model that we used to estimate the prevalence of COPD in people aged 30 years or more.

FINDINGS

Our search returned 37 472 publications. A total of 123 studies based on a spirometry-defined prevalence were retained for the review. From the meta-regression epidemiological model, we estimated about 227.3 million COPD cases in the year 1990 among people aged 30 years or more, corresponding to a global prevalence of 10.7% (95% confidence interval (CI) 7.3%-14.0%) in this age group. The number of COPD cases increased to 384 million in 2010, with a global prevalence of 11.7% (8.4%-15.0%). This increase of 68.9% was mainly driven by global demographic changes. Across WHO regions, the highest prevalence was estimated in the Americas (13.3% in 1990 and 15.2% in 2010), and the lowest in South East Asia (7.9% in 1990 and 9.7% in 2010). The percentage increase in COPD cases between 1990 and 2010 was the highest in the Eastern Mediterranean region (118.7%), followed by the African region (102.1%), while the European region recorded the lowest increase (22.5%). In 1990, we estimated about 120.9 million COPD cases among urban dwellers (prevalence of 13.2%) and 106.3 million cases among rural dwellers (prevalence of 8.8%). In 2010, there were more than 230 million COPD cases among urban dwellers (prevalence of 13.6%) and 153.7 million among rural dwellers (prevalence of 9.7%). The overall prevalence in men aged 30 years or more was 14.3% (95% CI 13.3%-15.3%) compared to 7.6% (95% CI 7.0%-8.2%) in women.

CONCLUSIONS

Our findings suggest a high and growing prevalence of COPD, both globally and regionally. There is a paucity of studies in Africa, South East Asia and the Eastern Mediterranean region. There is a need for governments, policy makers and international organizations to consider strengthening collaborations to address COPD globally.

Prevalence and risk factors for COPD in greenhouse farmers: a large, cross-sectional survey of 5,880 farmers from northeast China

Background

COPD is one of the most common chronic diseases, and more and more farmers who were frequently exposed to greenhouse environments were diagnosed with COPD. However, little information is available on the prevalence of COPD among the greenhouse farmers. This study was conducted to assess the prevalence of COPD and investigate the potential risk factors for COPD among the Chinese greenhouse farmers.

Methods

Cross-sectional studies involving a sample of greenhouse farmers living in northeast China were performed via stratified-cluster-random sampling. All subjects were interviewed using a uniform questionnaire and underwent pulmonary function tests between 2006 and 2009, based on the diagnostic criteria of the Global Initiative for Chronic Obstructive Lung Disease. Multiple logistic regression analysis was conducted to examine the risk factors for COPD.

Results

Of the 5,880 greenhouse farmers from northeast China who were originally selected for this study, 5,420 questionnaires were completed. The overall prevalence of COPD in greenhouse farmers was 17.5%. The COPD prevalence was significantly higher in elderly subjects (≥50 years), current smokers, in those with lower body mass index (≤18.5 kg/m²) and less education, in those who were exposed to mushroom, flowers and poultry, and in those living in mountain and coastal region. Multiple logistic regression analysis revealed that age over 50 years old (odds ratio [OR]=298.69, 95% confidence interval [CI]=121.57–733.84), smoking (OR=2.18, 95% CI=1.84–2.59), planting mushroom and flowers (OR=1.46 and 1.53, 95% CI=1.13–1.87 and 1.24–1.95), and living in mountain and coastal region (OR=1.68 and 1.35, 95% CI=1.37–2.06 and 1.10–1.65) were associated with the development of COPD among greenhouse farmers.

Conclusion

In northeast China, COPD is highly prevalent among greenhouse farmers, and advanced age, smoking, planting mushroom, and flowers, as well as living in mountain and coastal regions, are potential risk factors for this disease.

Respiratory symptoms, lung function decrement and chronic obstructive pulmonary disease in pre-menopausal Indian women exposed to biomass smoke

BACKGROUND

The impact of chronic exposure to smoke from biomass burning on respiratory health has been examined.

METHODS

Six-hundred and eighty-one non-smoking women (median age 35 years) from eastern India who cook exclusively with biomass (wood, dung and crop residues) and 438 age-matched women from similar neighborhood who cook with liquefied petroleum gas (LPG) were examined. Pulmonary function test was done by spirometry. The concentrations of particulate matter having diameter of < 10 µm (PM10) and < 2.5 µm (PM2.5) in indoor air was measured by real-time aerosol monitor.

RESULTS

Compared with LPG users, biomass users had greater prevalence of upper (50.9 versus 28.5%) and lower respiratory symptoms (71.8 versus 30.8%) and dyspnea (58.4 versus 19.9%). They showed reduction in all parameters measured by spirometer especially in mid-expiratory volume. PM10 and PM2.5 concentration in biomass using kitchen were 2-3-times more than LPG-using kitchen, and the decline in spirometry values was positively associated PM10 and PM2.5 levels in indoor air after controlling education, family income and kitchen location as potential confounders. Overall, 29.7% of biomass users and 16.4% of LPG users had deficient lung function, and restrictive type of deficiency was predominant. Chronic obstructive pulmonary disease (COPD) was diagnosed in 4.6% of biomass and 0.9% of LPG users. Women who predominantly used dung cake and did not possess separate kitchen had poorer lung function.

CONCLUSION

Cumulative exposure to biomass smoke causes lung function decrement and facilitates COPD development even in non-smoking and relatively young pre-menopausal women.

Meta-analysis approach to study the prevalence of chronic obstructive pulmonary disease among current, former and non-smokers

Comparative risk assessment for Chronic Obstructive Pulmonary Disease (COPD) among current, former and non-smokers categories remains controversial and not studied in detail. We conducted a meta-analysis to summarize all the relevant published studies on this topic and to update the association between smoking and prevalence of COPD in current, former and non-smokers. Identification, screening, eligibility and inclusion of articles for the study were conducted as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Quality assessment of included studies was undertaken using a scoring sheet. Meta-analysis after the final synthesis of the selected studies was performed using the STATA and Comprehensive Meta-Analysis (CMA) software. Estimates from forty two independent studies reporting 547,391 individuals were identified. Twenty two studies were conducted in Europe, nine in America and ten in Asia and one from New Zealand. The meta-analysis showed that the prevalence of COPD was significantly higher in current smokers compared with former and non-smokers. However, owing to large heterogeneity among the estimates obtained from the studies, stratification was done with respect to continent, diagnostic criteria of COPD and study design which also showed similar results. The stratified analysis also revealed similar trend of results with prevalence of COPD being higher in current smokers as compared to former and non-smokers. The present meta-analysis highlights the positive association between smoking and COPD prevalence. There is an urgent need to implement more effective policies towards the restriction of tobacco use, to reduce the burden of COPD.

Prevalence and determinants of self-reported chronic bronchitis among women in rural Central India

BACKGROUND

Chronic respiratory conditions are increasingly becoming a cause of health concern with India attributing 11% of its mortality due to non-communicable diseases to chronic respiratory conditions. Chronic bronchitis and asthma take a large toll in terms of morbidity. Lesser number of studies have mentioned their counts of these conditions affecting women in rural area and therefore the present study was conducted with the objectives of determining the prevalence and correlates of chronic obstructive pulmonary diseases (COPD) in an area of a primary health centre in rural central India.

METHODS

A cross-sectional study was conducted in 24 villages of the study area. Women aged 40 years or more were interviewed using the IUATLD questionnaire. Chronic bronchitis was measured by using the standard criteria for chronic bronchitis, that is, "Presence of cough with expectoration for more than 3 months in a year for the past two or more years".

RESULTS

Prevalence of chronic bronchitis among women was found to be 2.7%. Factors like older age, presence of a cattle shed within house premises, storage of fertilizers inside house, history of allergy, past history of pulmonary tuberculosis emerged as significant correlates of chronic bronchitis.

CONCLUSIONS

The present study provides an insight into the prevalence of chronic bronchitis among rural women exposed to several epidemiological determinants and an opportunity to address the modifiable risk factors.

Effects of cooking fuel smoke on respiratory symptoms and lung function in semi-rural women in Cameroon

BACKGROUND

Indoor air pollution is a major health problem in the developing world. In sub-Saharan Africa more than 90% of people rely on biomass to meet their domestic energy demands. Pollution from biomass fuel ranks 10th among preventable risk factors contributing to the global burden of diseases.

OBJECTIVES

The present study aimed to determine the prevalence of respiratory symptoms and the factors associated with reduced lung function in a population of women exposed to cooking fuel smoke.

METHODS

A cross-sectional study was conducted in a semi-rural area in Cameroon. We compared forced respiratory volume between women using wood (n = 145) and women using alternative sources of energy (n = 155) for cooking.

RESULTS

Chronic bronchitis was found in 7·6% of the wood smoke group and 0·6% in the alternative fuels group. We observed two cases of airflow obstruction in the wood smoke group. Factors associated with lung function impairment were chronic bronchitis, use of wood as cooking fuel, age, and height.

CONCLUSION

Respiratory symptoms and reduced lung function are more pronounced among women using wood as cooking fuel. Improved stoves technology should be developed to reduce the effects of wood smoke on respiratory health.

Disease burden due to biomass cooking-fuel-related household air pollution among women in India

Background

Household air pollution (HAP) due to biomass cooking fuel use is an important risk factor for a range of diseases, especially among adult women who are primary cooks, in India. About 80% of rural households in India use biomass fuel for cooking. The aim of this study is to estimate the attributable cases (AC) for four major diseases/conditions associated with biomass cooking fuel use among adult Indian women.

Methods

We used the population attributable fraction (PAF) method to calculate the AC of chronic bronchitis, tuberculosis (TB), cataract, and stillbirths due to exposure to biomass cooking fuel. A number of data sources were accessed to obtain population totals and disease prevalence rates. A meta-analysis was conducted to obtain adjusted pooled odds ratios (ORs) for strength of association. Using this, PAF and AC were calculated using a standard formula. Results were presented as number of AC and 95% confidence intervals (CI).

Results

The fixed effects pooled OR obtained from the meta-analysis were 2.37 (95% CI: 1.59, 3.54) for chronic bronchitis, 2.33 (1.65, 3.28) for TB, 2.16 (1.42, 3.26) for cataract, and 1.26 (1.12, 1.43) for stillbirths. PAF varied across conditions being maximum (53%) for chronic bronchitis in rural areas and least (1%) for cataract in older age and urban areas. About 2.4 (95% CI: 1.4, 3.1) of 5.6 m cases of chronic bronchitis, 0.3 (0.2, 0.4) of 0.76 m cases of TB, 5.0 (2.8, 6.7) of 51.4 m cases of cataract among adult Indian women and 0.02 (0.01, 0.03) of 0.15 m stillbirths across India are attributable to HAP due to biomass cooking fuel. These estimates should be cautiously interpreted in the light of limitations discussed which relate to exposure assessment, exposure characterization, and age-specific prevalence of disease.

Conclusions

HAP due to biomass fuel has diverse and major impacts on women’s health in India. Although challenging, incorporating the agenda of universal clean fuel access or cleaner technology within the broader framework of rural development will go a long way in reducing disease burden.

Oxidative/Nitrosative stress and the pathobiology of chronic obstructive pulmonary disease

The understanding of the pathobiology of Chronic Obstructive Pulmonary Disease (COPD) has undergone a major change in the past three decades. The classical 'protease-antiprotease' hypothesis still holds true, nevertheless, the sequence of the biochemical events which lead to the protease/antiprotease imbalance have been unraveled. For instance, tobacco smoke, a primary risk factor for COPD, contains a plethora of reactive Oxygen/Nitrogen Species (ROS/RNS) that serve to initiate the oxidant/antioxidant imbalance in the respiratory tract of chronic smokers, a phenomenon that is amplified if certain other risk factors co-exist (e.g. a genetic deficiency of the major antiproteases, a suboptimal antioxidant defense system, airway hyper responsiveness etc.). The inflammatory response that ensues as a result of the initial occult exogenous oxidative/ nitrosative stress becomes a secondary endogenous source of ROS/RNS. This perpetuates the ongoing lung damage, even though the primary insult may no longer be present (abstinence). Depletion of the pulmonary antioxidants, damage to the local antiprotease protective screen, a decreased immune response, hypersecretion of mucus, superadded infections, oxygen therapy-induced oxidant production, etc. are some of the critical factors which account for the oxidative/ nitrosative stress-mediated pulmonary as well as extrapulmonary features of COPD. In the light of the recent developments, remarkable efforts are being made, either to develop novel therapeutic strategies or to improve the existing ones, which are aimed at treating different aspects of the disease. Thus, it is reasonable to recommend antioxidants as a useful adjunct to the more conventional treatment options, keeping in view the 'oxidant/antioxidant' hypothesis as a unifying theme for the 'protease/antiprotease' theory of COPD.

A comparison of the inflammatory and proteolytic effects of dung biomass and cigarette smoke exposure in the lung

Rationale

Biomass is the energy source for cooking and heating for billions of people worldwide. Despite their prevalent use and their potential impact on global health, the effects of these fuels on lung biology and function remain poorly understood.

Methods

We exposed human small airway epithelial cells and C57BL/6 mice to dung biomass smoke or cigarette smoke to compare how these exposures impacted lung signaling and inflammatory and proteolytic responses that have been linked with disease pathogenesis.

Results

The in vitro exposure and siRNA studies demonstrated that biomass and cigarette smoke activated ERK to up regulate IL-8 and MMP-1 expression in human airway epithelial cells. In contrast to cigarette smoke, biomass also activated p38 and JNK within these lung cells and lowered the expression of tissue inhibitor of matrix metalloproteinase-1 (TIMP-1). Similarly, in the lungs of mice, both biomass and cigarette smoke exposure increased macrophages, activated ERK and p38 and up regulated MMP-9 and MMP-12 expression. The main differences seen in the exposure studies was that mice exposed to biomass exhibited more perivascular inflammation and had higher G-CSF and GM-CSF lavage fluid levels than mice exposed identically to cigarette smoke.

Conclusion

Biomass activates similar pathogenic processes seen in cigarette smoke exposure that are known to result in the disruption of lung structure. These findings provide biological evidence that public health interventions are needed to address the harm associated with the use of this fuel source.