scholarly journals Non-communicable respiratory disease and air pollution exposure in Malawi: a prospective cohort study

Thorax ◽  
2020 ◽  
Vol 75 (3) ◽  
pp. 220-226 ◽  
Author(s):  
Sarah Rylance ◽  
Chris Jewell ◽  
Andrew Naunje ◽  
Frank Mbalume ◽  
John D Chetwood ◽  
...  

RationaleThere are no population-based studies from sub-Saharan Africa describing longitudinal lung function in adults.ObjectivesTo explore the lung function trajectories and their determinants, including the effects of air pollution exposures and the cleaner-burning biomass-fuelled cookstove intervention of the Cooking and Pneumonia Study (CAPS), in adults living in rural Malawi.MethodsWe assessed respiratory symptoms and exposures, spirometry and measured 48-hour personal exposure to fine particulate matter (PM2.5) and carbon monoxide (CO), on three occasions over 3 years. Longitudinal data were analysed using mixed-effects modelling by maximum likelihood estimation.Measurements and main resultsWe recruited 1481 adults, mean (SD) age 43.8 (17.8) years, including 523 participants from CAPS households (271 intervention; 252 controls), and collected multiple spirometry and air pollution measurements for 654 (44%) and 929 (63%), respectively. Compared with Global Lung Function Initiative African-American reference ranges, mean (SD) FEV1 (forced expiratory volume in 1 s) and FVC (forced vital capacity) z-scores were −0.38 (1.14) and −0.19 (1.09). FEV1 and FVC were determined by age, sex, height, previous TB and body mass index, with FEV1 declining by 30.9 mL/year (95% CI: 21.6 to 40.1) and FVC by 38.3 mL/year (95% CI: 28.5 to 48.1). There was decreased exposure to PM2.5 in those with access to a cookstove but no effect on lung function.ConclusionsWe did not observe accelerated lung function decline in this cohort of Malawian adults, compared with that reported in healthy, non-smoking populations from high-income countries; this suggests that the lung function deficits we measured in adulthood may have origins in early life.

2018 ◽  
Vol 51 (4) ◽  
pp. 1702536 ◽  
Author(s):  
Robert J. Hancox ◽  
Ian D. Pavord ◽  
Malcolm R. Sears

Eosinophilic inflammation and airway remodelling are characteristic features of asthma, but the association between them is unclear. We assessed associations between blood eosinophils and lung function decline in a population-based cohort of young adults.We used linear mixed models to analyse associations between blood eosinophils and spirometry at 21, 26, 32 and 38 years adjusting for sex, smoking, asthma and spirometry at age 18 years. We further analysed associations between mean eosinophil counts and changes in spirometry from ages 21 to 38 years.Higher eosinophils were associated with lower forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratios and lower FEV1 % predicted values for both pre- and post-bronchodilator spirometry (all p-values ≤0.048). Although eosinophil counts were higher in participants with asthma, the associations between eosinophils and spirometry were similar among participants without asthma or wheeze. Participants with mean eosinophil counts >0.4×109 cells·L−1 between 21 and 38 years had greater declines in FEV1/FVC ratios (difference 1.8%, 95% CI 0.7–2.9%; p=0.001) and FEV1 values (difference 3.4% pred, 95% CI 1.5–5.4% pred); p=0.001) than those with lower counts.Blood eosinophils are associated with airflow obstruction and enhanced decline in lung function, independently of asthma and smoking. Eosinophilia is a risk factor for airflow obstruction even in those without symptoms.


2015 ◽  
Vol 47 (3) ◽  
pp. 742-750 ◽  
Author(s):  
Suneela Zaigham ◽  
Per Wollmer ◽  
Gunnar Engström

The use of baseline lung function in the prediction of chronic obstructive pulmonary disease (COPD) hospitalisations, all-cause mortality and lung function decline was assessed in the population-based “Men Born in 1914” cohort.Spirometry was assessed at age 55 years in 689 subjects, of whom 392 had spirometry reassessed at age 68  years. The cohort was divided into three groups using fixed ratio (FR) and lower limit of normal (LLN) criterion: forced expiratory volume in 1 s (FEV1)/vital capacity (VC) ≥70%, FEV1/VC <70% but ≥LLN (FR+LLN−), and FEV1/VC <70% and <LLN (FR+LLN+).Over 44 years of follow-up, 88 men were hospitalised due to COPD and 686 died. Hazard ratios (95% CI) for incident COPD hospitalisation were 4.15 (2.24–7.69) for FR+LLN− and 7.88 (4.82–12.87) for FR+LLN+ (reference FEV1/VC ≥70%). Hazard ratios for death were 1.30 (0.98–1.72) for FR+LLN− and 1.58 (1.25–2.00) for FR+LLN+. The adjusted FEV1 decline between 55 and 68 years of age was higher for FR+LLN− and FR+LLN+ relative to the reference. Of those with FR+LLN− at 55 years, 53% had progressed to the FR+LLN+ group at 68 years.Airflow obstruction at age 55 years is a powerful risk factor for future COPD hospitalisations. The FR+LLN− group should be carefully evaluated in clinical practice in relation to future risks and potential benefit from early intervention. This is reinforced by the increased FEV1 decline in this group.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242226
Author(s):  
Martin W. Njoroge ◽  
Sarah Rylance ◽  
Rebecca Nightingale ◽  
Stephen Gordon ◽  
Kevin Mortimer ◽  
...  

Purpose The aim of this article is to provide a detailed description of the Chikwawa lung health cohort which was established in rural Malawi to prospectively determine the prevalence and causes of lung disease amongst the general population of adults living in a low-income rural setting in Sub-Saharan Africa. Participants A total of 1481 participants were randomly identified and recruited in 2014 for the baseline study. We collected data on demographic, socio-economic status, respiratory symptoms and potentially relevant exposures such as smoking, household fuels, environmental exposures, occupational history/exposures, dietary intake, healthcare utilization, cost (medication, outpatient visits and inpatient admissions) and productivity losses. Spirometry was performed to assess lung function. At baseline, 56.9% of the participants were female, mean age was 43.8 (SD:17.8) and mean body mass index (BMI) was 21.6 Kg/m2 (SD: 3.46) Findings to date The cohort has reported the prevalence of chronic respiratory symptoms (13.6%, 95% confidence interval [CI], 11.9–15.4), spirometric obstruction (8.7%, 95% CI, 7.0–10.7), and spirometric restriction (34.8%, 95% CI, 31.7–38.0). Additionally, an annual decline in forced expiratory volume in one second [FEV1] of 30.9mL/year (95% CI: 21.6 to 40.1) and forced vital capacity [FVC] by 38.3 mL/year (95% CI: 28.5 to 48.1) has been reported. Future plans The ongoing phases of follow-up will determine the annual rate of decline in lung function as measured through spirometry and the development of airflow obstruction and restriction, and relate these to morbidity, mortality and economic cost of airflow obstruction and restriction. Population-based mathematical models will be developed driven by the empirical data from the cohort and national population data for Malawi to assess the effects of interventions and programmes to address the lung burden in Malawi. The present follow-up study started in 2019.


2020 ◽  
pp. 2000838 ◽  
Author(s):  
Wan C. Tan ◽  
Jean Bourbeau ◽  
Gilbert Nadeau ◽  
Wendy Wang ◽  
Neil Barnes ◽  
...  

IntroductionThe aim of this study was to examine the association between blood eosinophil (EOS) levels and the decline in lung function in individuals over the age of 40 from the general population.MethodsThe study evaluated the EOS counts from thawed blood in 1120 participants (mean age 65 years) from the prospective population-based Canadian Cohort of Obstructive Lung Disease (CanCOLD) study. Participants answered interviewer-administered respiratory questionnaires and performed pre-/post-bronchodilator spirometric tests at 18-month intervals; computed tomography (CT) imaging was performed at baseline. Statistical analyses to describe the relationship between EOS levels and decline in forced expiratory volume in 1 s (FEV1) were performed using random mixed effects regression models with adjustments for demographics, smoking, baseline FEV1, ever-asthma and history of exacerbations in the previous 12 months. CT measurements were compared between EOS subgroups using an analysis of variance.ResultsParticipants who had a peripheral EOS count of ≥300 cells·µL−1 (n=273) had a greater decline in FEV1 compared with those with EOS counts of <150 cells·µL−1 (n=430) [p=0.003] (reference group) and 150 to <300 cells·µL−1 (n=417) [p=0.003]. The absolute change in FEV1 was −32.99 mL·year−1 for participants with EOS counts <150 cells·µL−1; −38.78 mL·year−1 for those with 150 to <300 cells·µL−1; and −67.30 mL·year−1 for participants with ≥300 cells·µL−1. In COPD, higher EOS count was associated with quantitative CT measurements reflecting both small and large airway abnormalities.ConclusionA blood EOS count of ≥300 cells·µL−1 is an independent risk factor for accelerated lung function decline in older adults and is related to undetected structural airway abnormalities.


2019 ◽  
Vol 55 (1) ◽  
pp. 1901217 ◽  
Author(s):  
Sara Renata Alex Wijnant ◽  
Emmely De Roos ◽  
Maryam Kavousi ◽  
Bruno Hugo Stricker ◽  
Natalie Terzikhan ◽  
...  

Preserved ratio impaired spirometry (PRISm) is a heterogeneous condition but its course and disease progression remain to be elucidated. We aimed to examine its prevalence, trajectories and prognosis in the general population.In the Rotterdam Study (population-based prospective cohort) we examined prevalence, trajectories and prognosis of subjects with normal spirometry (controls; forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ≥0.7, FEV1  ≥80%), PRISm (FEV1/FVC ≥0.7, FEV1 <80%) and chronic obstructive pulmonary disease (COPD) (FEV1/FVC <0.7) at two study visits. Hazard ratios with 95% confidence intervals for mortality (until December 30, 2018) were adjusted for age, sex, body mass index, current smoking and pack-years.Of 5487 subjects (age 69.1±8.9 years; 7.1% PRISm), 1603 were re-examined after 4.5 years. Of the re-examined PRISm subjects, 15.7% transitioned to normal spirometry and 49.4% to COPD. Median lung function decline was highest in subjects with incident PRISm (FEV1 −92.8 mL·year−1, interquartile range (IQR) −131.9– −65.8 mL·year−1; FVC −93.3 mL·year−1, IQR −159.8– −49.1 mL·year−1), but similar in persistent PRISm (FEV1 −30.2 mL·year−1, IQR −67.9– −7.5 mL·year−1; FVC −20.1 mL·year−1, IQR −47.7–21.7 mL·year−1) and persistent controls (FEV1 −39.6 mL·year−1, IQR −64.3–−12.7 mL·year−1; FVC −20.0 mL·year−1, IQR −55.4–18.8 mL·year−1). Of 5459 subjects with informed consent for follow-up, 692 (12.7%) died during 9.3 years (maximum) follow-up: 10.3% of controls, 18.7% of PRISm subjects and 20.8% of COPD subjects. Relative to controls, subjects with PRISm and COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) 2–4 had increased all-cause mortality (PRISm: HR 1.6, 95% CI 1.2–2.0; COPD GOLD 2–4: HR 1.7, 95% CI 1.4–2.1) and cardiovascular mortality (PRISm: HR 2.8, 95% CI 1.5–5.1; COPD 2–4: HR 2.1, 95% CI 1.2–3.6). Mortality within <1 year was highest in PRISm, with patients often having cardiovascular comorbidities (heart failure or coronary heart disease; 70.0%).PRISm is associated with increased mortality and this population encompasses at least three distinct subsets: one that develops COPD during follow-up, a second with high cardiovascular burden and early mortality, and a third with persistent PRISm and normal age-related lung function decline.


2020 ◽  
Vol 6 (3) ◽  
pp. 00070-2020
Author(s):  
Alexandra Lenoir ◽  
Elaine Fuertes ◽  
Francisco Gómez-Real ◽  
Benedicte Leynaert ◽  
Diana A. van der Plaat ◽  
...  

Higher levels of testosterone have been associated with better lung function in cross-sectional population-based studies. The role of testosterone in lung function in women and in lung function decline in men or women is unclear.We studied 5114 men and 5467 women in the UK Biobank with high-quality spirometry at baseline (2006–2010) and 8.4 years later. We studied cross-sectional associations of total testosterone (TT), calculated free testosterone (cFT), free androgen index (FAI) and sex hormone-binding globulin (SHBG) with forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC) and FEV1/FVC using linear regression and associations of baseline markers with lung function decline using linear mixed-effects regression.Men with higher levels of TT had higher FEV1 (27.56 mL per interquartile range increase TT, 95% CI 5.43–49.68) and FVC (48.06 mL, 95% CI 22.07–74.06) at baseline. Higher cFT levels were associated with higher FEV1 and FVC among physically active men only. In women, higher FAI and cFT levels were associated with lower lung function at baseline and higher levels of TT, cFT and FAI were associated with slightly attenuated FEV1 and FVC decline. Higher levels of SHBG were associated with better lung function in both sexes but slightly accelerated decline in men.In this population-based sample, higher levels of TT were associated with better lung function in men and higher levels of cFT with better lung function in physically active men. A small attenuation of lung function decline with higher levels of TT, cFT and FAI was seen in women only.


2019 ◽  
Vol 76 (12) ◽  
pp. 888-894 ◽  
Author(s):  
Andreas M Neophytou ◽  
Sadie Costello ◽  
Sally Picciotto ◽  
Elizabeth M Noth ◽  
Sa Liu ◽  
...  

ObjectiveOccupational dust exposure has been associated with accelerated lung function decline, which in turn is associated with overall morbidity and mortality. In the current study, we assess potential benefits on lung function of hypothetical interventions that would reduce occupational exposure to fine particulate matter (PM2.5) while adjusting for the healthy worker survivor effect.MethodsAnalyses were performed in a cohort of 6485 hourly male workers in an aluminium manufacturing company in the USA, followed between 1996 and 2013. We used the parametric g-formula to assess lung function decline over time under hypothetical interventions while also addressing time-varying confounding by underlying health status, using a composite risk score based on health insurance claims.ResultsA counterfactual scenario envisioning a limit on exposure equivalent to the 10th percentile of the observed exposure distribution of 0.05 mg/m3 was associated with an improvement in forced expiratory volume in one second (FEV1) equivalent to 37.6 mL (95% CI 13.6 to 61.6) after 10 years of follow-up when compared with the observed. Assuming a linear decrease and (from NHANES reference values), a 20 mL decrease per year for a 1.8 m-tall man as they age, this 37.6 mL FEV1 loss over 10 years associated with observed exposure would translate to approximately a 19% increase to the already expected loss per year from age alone.ConclusionsOur results indicate that occupational PM2.5 exposure in the aluminium industry accelerates lung function decline over age. Reduction in exposure may mitigate accelerated loss of lung function over time in the industry.


2018 ◽  
Vol 2018 (1) ◽  
Author(s):  
Shyfuddin Ahmed ◽  
Muhammad Ashique Haider Chowdhury ◽  
Mohammad Hasan Shahriar ◽  
Mahbubul Eunus ◽  
Shirmin Bintay Kader ◽  
...  

2020 ◽  
Vol 189 (10) ◽  
pp. 1173-1184
Author(s):  
Talea Cornelius ◽  
Joseph E Schwartz ◽  
Pallavi Balte ◽  
Surya P Bhatt ◽  
Patricia A Cassano ◽  
...  

Abstract The relationship between body weight and lung function is complex. Using a dyadic multilevel linear modeling approach, treating body mass index (BMI; weight (kg)/height (m)2) and lung function as paired, within-person outcomes, we tested the hypothesis that persons with more rapid increase in BMI exhibit more rapid decline in lung function, as measured by forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and their ratio (FEV1:FVC). Models included random intercepts and slopes and adjusted for sociodemographic and smoking-related factors. A sample of 9,115 adults with paired measurements of BMI and lung function taken at ≥3 visits were selected from a pooled set of 5 US population-based cohort studies (1983–2018; mean age at baseline = 46 years; median follow-up, 19 years). At age 46 years, average annual rates of change in BMI, FEV1, FVC, and FEV1:FVC ratio were 0.22 kg/m2/year, −25.50 mL/year, −21.99 mL/year, and −0.24%/year, respectively. Persons with steeper BMI increases had faster declines in FEV1 (r = −0.16) and FVC (r = −0.26) and slower declines in FEV1:FVC ratio (r = 0.11) (all P values &lt; 0.0001). Results were similar in subgroup analyses. Residual correlations were negative (P &lt; 0.0001), suggesting additional interdependence between BMI and lung function. Results show that greater rates of weight gain are associated with greater rates of lung function loss.


Author(s):  
Ashley K. Dores ◽  
Gordon H. Fick ◽  
Frank P. MacMaster ◽  
Jeanne V. A. Williams ◽  
Andrew G. M. Bulloch ◽  
...  

To assess whether exposure to increased levels of outdoor air pollution is associated with psychological depression, six annual iterations of the Canadian Community Health Survey (n ≈ 127,050) were used to estimate the prevalence of a major depressive episode (2011–2014) or severity of depressive symptoms (2015–2016). Survey data were linked with outdoor air pollution data obtained from the Canadian Urban Environmental Health Research Consortium, with outdoor air pollution represented by fine particulate matter ≤2.5 micrometers (μm) in diameter (PM2.5), ozone (O3), sulfur dioxide (SO2), and nitrogen dioxide (NO2). Log-binomial models were used to estimate the association between outdoor air pollution and depression, and included adjustment for age, sex, marital status, income, education, employment status, urban versus rural households, cigarette smoking, and chronic illness. No evidence of associations for either depression outcomes were found. Given the generally low levels of outdoor air pollution in Canada, these findings should be generalized with caution. It is possible that a meaningful association with major depression may be observed in regions of the world where the levels of outdoor air pollution are greater, or during high pollution events over brief time intervals. Future research is needed to replicate these findings and to further investigate these associations in other regions and populations.


Sign in / Sign up

Export Citation Format

Share Document