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.

Impact of biomass fuel exposure from traditional stoves on lung functions in adult women of a rural Indian village.

INTRODUCTION: Exposure to biomass fuel (BMF) from traditional cookstoves inflicts an enormous burden of morbidities in women across the developing world. This study aims to assess the lung function and its association with the indoor air pollutants generated using BMF. MATERIALS AND METHODS: This cross-sectional study including 310 women was conducted in a rural village of India. Households were divided into two groups based on the cooking fuel, the BMF group and the liquefied petroleum gas (LPG) group. Information on respiratory symptoms and socioeconomic status was obtained using a standard questionnaire. Indoor air concentration for PM10and PM2.5was measured during cooking hours. Pulmonary function tests (PFTs) were conducted for the women inhabitants. RESULTS: On comparing the two groups, the concentration of PM10(890.26 ± 59.59 vs. 148.66 ± 31.97) µg/m3 and PM2.5(728.90 ± 50.20 vs. 99.76 ± 41.80) µg/m3 (P < 0.01) were higher in the group using BMF. The respiratory symptoms such as wheezing, dyspnea, chronic cough, and nocturnal cough, were significantly more common in the group using BMF. A significant difference was seen in the lung function indices between the two groups. A significant negative correlation of respiratory indices with duration of exposure and the particulate matter (PM) values suggested a greater decline on lung function among women exposed to increased concentrations of PM. On comparing participants with normal and abnormal PFT, it was seen that the use of BMF (odds ratio [OR] 8.01; 95% confidence interval [CI] 4.80, 13.36, P < 0.001) and the duration of exposure to BMF (OR 1.16; 95% CI 1.13, 1.20., P < 0.001) increased the odds of having an abnormal PFT. CONCLUSIONS: This study shows a high prevalence of respiratory symptoms and an abnormal pulmonary function in women exposed to BMF.

Management of anastomotic biliary stricture after liver transplantation: metal versus plastic stent.

BACKGROUND: Post-transplant anastomotic biliary strictures remain refractory to endoscopic therapy in a considerable number of cases. The aim of this meta-analysis was to compare fully-covered self-expandable metal and plastic stents in the management of post-transplant biliary strictures. METHODS: A meta-analysis was performed using a random effects model; results were expressed as odds ratio (OR) and mean standardized difference. The primary outcome was stricture resolution, while recurrence rate after stent placement, treatment time, and safety of the procedure were the secondary outcomes. RESULTS: Through a systematic literature review until October 2017, we identified 7 studies, of which 4 were randomized controlled trials. Stricture resolution was slightly higher with metal stents, with no statistical difference between the two procedures (OR 1.38, 95% confidence interval [CI] 0.60-3.15; P=0.45) and low heterogeneity (I2=6%). Stricture recurrence showed a non-significant trend in favor of plastic stents (OR 1.82, 95%CI 0.52-6.31, P=0.35). Endoscopic retrograde cholangiopancreatography with placement of metal stents offered a significant improvement in terms of reduced treatment time (mean standardized difference: -3.58 months, 95%CI -6.23 to -0.93; P=0.008), but with more frequent complications, although not significantly so (OR 2.34, 95%CI 0.75-7.25; P=0.14). Sensitivity analysis confirmed all the findings. CONCLUSION: Metal stents appear to be a promising tool that can decrease treatment time, although there is still no clear evidence of their superiority over plastic stents in terms of efficacy.