Aneesa Vanker

Home environment and indoor air pollution exposure in an African birth cohort study

BACKGROUND Household indoor air pollution (IAP) is a global health problem and a risk factor for childhood respiratory disease; the leading cause of mortality in African children. This study aimed to describe the home environment and measure IAP in the Drakenstein Child Health Study (DCHS), an African birth cohort. METHODS An antenatal home visit to assess the home environment and measure IAP (particulate matter, sulphur dioxide, nitrogen dioxide, carbon monoxide and volatile organic compounds (VOCs)) was done on pregnant women enrolled to the DCHS, in a low-socioeconomic, peri-urban South African community. Urine cotinine measured maternal tobacco smoking and exposure. Dwellings were categorised according to 6 household dimensions. Univariate and multivariate analysis explored associations between home environment, seasons and IAP levels measured. RESULTS 633 home visits were completed, with IAP measured in 90% of homes. Almost a third of participants were of the lowest socio-economic status and the majority of homes (65%) lacked 2 or more of the dwelling category dimensions. Most households had electricity (92%), however, fossil fuels were still used for cooking (19%) and heating (15%) in homes. Antenatal maternal smoking prevalence was 31%; 44% had passive smoke exposure. Of IAP measured, benzene (VOC) was significantly above ambient standards with median 5.6 μg/m3 (IQR 2.6-17.1). There were significant associations between the use of fossil fuels for cooking and increased benzene [OR 3.4 (95% CI 2.1-5.4)], carbon monoxide [OR 2.9 (95% CI 1.7-5.0)] and nitrogen dioxide [OR 18.6 (95% CI 3.9-88.9)] levels. A significant seasonal association was found with higher IAP levels in winter. CONCLUSION In this low-socioeconomic African community, multiple environmental factors and pollutants, with the potential to affect child health, were identified. Measurement of IAP in a resource-limited setting is feasible. Recognising and quantifying these risk factors is important in effecting public health policy changes.

Lung Function in African Infants in the Drakenstein Child Health Study: Impact of Lower Respiratory Tract Illness.

Rationale: Lower respiratory tract illness is a major cause of childhood morbidity and mortality. It is unknown whether infants are predisposed to illness because of impaired lung function or whether respiratory illness reduces lung function. Objectives: To investigate the impact of early life exposures, including lower respiratory tract illness, on lung function during infancy. Methods: Infants enrolled in the Drakenstein child health study had lung function at 6 weeks and 1 year. Testing during quiet natural sleep included tidal breathing, exhaled nitric oxide, and multiple breath washout measures. Risk factors for impaired lung health were collected longitudinally. Lower respiratory tract illness surveillance was performed and any episode investigated. Measurements and Main Results: Lung function was tested in 648 children at 1 year. One hundred and fifty (29%) infants had a lower respiratory tract illness during the first year of life. Lower respiratory tract illness was independently associated with increased respiratory rate (4%; 95% confidence interval [CI], 1.01‐1.08; P = 0.02). Repeat episodes further increased respiratory rate (3%; 95% CI, 1.01‐1.05; P = 0.004), decreased tidal volume (−1.7 ml; 95% CI, −3.3 to −0.2; P = 0.03), and increased the lung clearance index (0.13 turnovers; 95% CI, 0.04‐0.22; P = 0.006) compared with infants without illness. Tobacco smoke exposure, lung function at 6 weeks, infant growth, and prematurity were other independent predictors of lung function at 1 year. Conclusions: Early life lower respiratory tract illness impairs lung function at 1 year, independent of baseline lung function. Preventing early life lower respiratory tract illness is important to optimize lung function and promote respiratory health in childhood.

Antenatal and early life tobacco smoke exposure in an African birth cohort study.

BACKGROUND Exposure to tobacco smoke in African infants has not been well studied, despite the high burden of childhood respiratory disease in these communities. OBJECTIVE To investigate the prevalence of antenatal and early life tobacco smoke exposure and associations with infant birth outcomes in an African birth cohort, the Drakenstein Child Health Study. METHODS Self-report questionnaires assessing maternal and household smoking were administered. Maternal and infant urine cotinine testing was conducted antenatally, at birth and at 6-10 weeks of life to measure tobacco smoke exposure. Multivariate regression models explored the associations between exposure to smoke and infant birth outcomes. RESULTS Of 789 pregnant women included, 250 (32%) were active smokers on cotinine testing. At birth and at 6-10 weeks of life, respectively 135/241 (56%) and 154/291 (53%) infants had urine cotinine levels indicating tobacco smoke exposure. Household smoking was prevalent and was associated with positive infant cotinine test results. Antenatal maternal smoking was associated with decreased infant birthweight-for-age Z-score (0.3, 95%CI 0.1-0.5). CONCLUSION Antenatal and early life tobacco smoke exposure is highly prevalent in this community, and may impact on birth outcomes and subsequent child health. Smoking cessation interventions are urgently needed to reduce tobacco smoke exposure in African communities.

Determinants of early-life lung function in African infants.

Background Low lung function in early life is associated with later respiratory illness. There is limited data on lung function in African infants despite a high prevalence of respiratory disease. Aim To assess the determinants of early lung function in African infants. Method Infants enrolled in a South African birth cohort, the Drakenstein child health study, had lung function measured at 6–10 weeks of age. Measurements, made with the infant breathing via a facemask during natural sleep, included tidal breathing, sulfur hexafluoride multiple breath washout and the forced oscillation technique. Information on antenatal and early postnatal exposures was collected using questionnaires and urine cotinine. Household benzene exposure was measured antenatally. Results Successful tests were obtained in 645/675 (95%) infants, median (IQR) age of 51 (46–58) days. Infant size, age and male gender were associated with larger tidal volume. Infants whose mothers smoked had lower tidal volumes (−1.6 mL (95% CI −3.0 to −0.1), p=0.04) and higher lung clearance index (0.1 turnovers (95% CI 0.01 to 0.3), p=0.03) compared with infants unexposed to tobacco smoke. Infants exposed to alcohol in utero or household benzene had lower time to peak tidal expiratory flow over total expiratory time ratios, 10% (95% CI −15.4% to −3.7%), p=0.002) and 3.0% (95% CI −5.2% to −0.7%, p=0.01) lower respectively compared with unexposed infants. HIV-exposed infants had higher tidal volumes (1.7 mL (95% CI 0.06 to 3.3) p=0.04) compared with infants whose mothers were HIV negative. Conclusion We identified several factors including infant size, sex, maternal smoking, maternal alcohol, maternal HIV and household benzene associated with altered early lung function, many of which are factors amenable to public health interventions. Long-term study of lung function and respiratory disease in these children is a priority to develop strategies to strengthen child health.

The association between environmental tobacco smoke exposure and childhood respiratory disease: a review

ABSTRACT Introduction: Childhood respiratory illness is a major cause of morbidity and mortality particularly in low and middle-income countries. Environmental tobacco smoke (ETS) exposure is a recognised risk factor for both acute and chronic respiratory illness. Areas covered: The aim of this paper was to review the epidemiology of ETS exposure and impact on respiratory health in children. We conducted a search of 3 electronic databases of publications on ETS and childhood respiratory illness from 1990–2015. Key findings were that up to 70% of children are exposed to ETS globally, but under-reporting may mask the true prevalence. Maternal smoking and ETS exposure influence infant lung development and are associated with childhood upper and lower respiratory tract infection, wheezing or asthma. Further, exposure to ETS is associated with more severe respiratory disease. ETS exposure reduces lung function early in life, establishing an increased lifelong risk of poor lung health. Expert commentary: Urgent and effective strategies are needed to decrease ETS exposure in young children to improve child and long-term lung health in adults especially in low and middle income countries where ETS exposure is increasing.

Early-life exposure to indoor air pollution or tobacco smoke and lower respiratory tract illness and wheezing in African infants: a longitudinal birth cohort study

Summary Background Indoor air pollution (IAP) and environmental tobacco smoke (ETS) are associated with lower respiratory tract illness (LRTI) or wheezing in children. However, the effect of the timing of these exposures, specifically antenatal versus postnatal, and of alternate fuel sources such as the increasingly used volatile organic compounds have not been well studied. We longitudinally investigated the effect of antenatal or postnatal IAP and ETS on LRTI or wheezing prevalence and severity in African infants. Methods Mother and infant pairs enrolled over a 3-year period in a birth cohort study in two centres in Paarl, South Africa, were followed for the first year of life for LRTI or wheezing illness. We measured exposure to IAP (particulate matter, nitrogen dioxide, sulphur dioxide, carbon monoxide, and volatile organic compounds benzene and toluene) using devices placed in homes, antenatally and postnatally. We measured ETS longitudinally by maternal self-report and by urine cotinine measures. Study staff trained in recognition of LRTI or wheeze documented all episodes, which were categorised according to WHO case definition criteria. We used multivariate logistic and Poisson regressions to explore associations. Findings Between March 1, 2012, and March 31, 2015, we enrolled 1137 mothers with 1143 livebirths. Of 1065 infants who attended at least one study visit, 524 episodes of LRTI occurred after discharge with a wheezing prevalence of 0·23 (95% CI 0·21–0·26) episodes per child year. Exposures associated with LRTI were antenatal maternal smoking (incidence rate ratio 1·62, 95% CI 1·14–2·30; p=0·004) or particulate matter (1·43, 1·06–1·95; p=0·008). Subanalyses of LRTI requiring hospitalisation (n=137) and supplemental oxygen (n=69) found antenatal toluene significantly increased the risk of LRTI-associated hospitalisation (odds ratio 5·13, 95% CI 1·43–18·36; p=0·012) and need for supplemental oxygen (13·21, 1·96–89·16; p=0·008). Wheezing illness was associated with both antenatal (incidence rate ratio 2·09, 95% CI 1·54–2·84; p<0·0001) and postnatal (1·27, 95% CI 1·03–1·56; p=0·024) maternal smoking. Antenatally, wheezing was associated with maternal passive smoke exposure (1·70, 1·25–2·31; p=0·001) and, postnatally, with any household member smoking (1·55, 1·17 −2·06; p=0·002). Interpretation Antenatal exposures were the predominant risk factors associated with LRTI or wheezing illness. Toluene was a novel exposure associated with severe LRTI. Urgent and effective interventions focusing on antenatal environmental factors are required, including smoking cessation programmes targeting women of childbearing age pre-conception and pregnant women. Funding Bill & Melinda Gates Foundation, Discovery Foundation, South African Thoracic Society AstraZeneca Respiratory Fellowship, Medical Research Council South Africa, National Research Foundation South Africa, and CIDRI Clinical Fellowship.

Electronic cigarette use in youths: a position statement of the Forum of International Respiratory Societies

Children and adolescents are highly susceptible to nicotine addiction, which affects their brain development, even in those who smoke infrequently. Young people who become addicted to nicotine are at greater risk of becoming lifelong tobacco consumers. The use of nicotine-delivering electronic cigarettes has risen dramatically among youths worldwide. In addition to physical dependence, adolescents are susceptible to social and environmental influences to use electronic cigarettes. The product design, flavours, marketing, and perception of safety and acceptability have increased the appeal of electronic cigarettes to young people, thus leading to new generations addicted to nicotine. Moreover, there is growing evidence that electronic cigarettes in children and adolescents serve as a gateway to cigarette smoking. There can be no argument for harm reduction in children. To protect this vulnerable population from electronic cigarettes and other nicotine delivery devices, we recommend that electronic cigarettes be regulated as tobacco products and included in smoke-free policies. Sale of electronic cigarettes should be barred to youths worldwide. Flavouring should be prohibited in electronic cigarettes, and advertising accessible by youths and young adults be banned. Finally, we recommend greater research on the health effects of electronic cigarettes and surveillance of use across different countries. It is the position of @lungsfirst that nicotine in electronic cigarettes poses a great threat to youth and we must protect them from it http://ow.ly/DfWJ30jIes7

Exogenous lipoid pneumonia: an important cause of interstitial lung disease in infants: Exogenous lipoid pneumonia in infants

Exogenous lipoid pneumonia (ELP), an important cause of interstitial lung disease, often goes unrecognized. We conducted a retrospective study of children with histologically confirmed ELP at Red Cross Children’s Hospital, South Africa. Twelve children of Zimbabwean heritage aged 2.1–10.8 months were identified between 2012 and 2017. Repeated oral administration of plant‐based oil for cultural reasons was reported by 10 of 11 caregivers. Cough (12/12), tachypnoea (11/12), hypoxia (9/12), and diffuse alveolar infiltrates on chest radiography (12/12) were common at presentation. Chest computed tomography revealed ground‐glass opacification with lower zone predominance (9/9) and interlobular septal thickening (8/9). Bronchoalveolar lavage specimens appeared cloudy/milky, with abundant lipid‐laden macrophages and extracellular lipid on Oil‐Red‐O staining (12/12), with polymicrobial (6/12) and Mycobacterium abscessus (2/12) co‐infection. Antibiotics, systemic corticosteroids, and therapeutic lavage were interventions in all eight and five patients, respectively. Clinicians should consider ELP in children with non‐resolving pneumonia in settings with similar practices.

The African Pediatric Fellowship Training Program in Pediatric Pulmonology: A Model for Growing African Capacity in Child Lung Health.

Childhood respiratory diseases are the major cause of mortality and morbidity in African children. However, there is limited expertise in pediatric pulmonology in Africa. The African Pediatric Fellowship Program (APFP) was developed in the Department of Paediatrics and Child Health at the University of Cape Town in partnership with African academic institutions beyond South Africa to promote training of African child health professionals and to build capacity. From 2008 to 2016, 11 fellows have completed APFP training in pediatric pulmonology. Fellows have come from Kenya, Nigeria, Ghana, and Uganda. All but one returned to their home institutions, where they are building academic departments, improving clinical service delivery, growing research capacity, and advancing advocacy and policies to improve child lung health. In parallel, training of South African pediatric pulmonologists has been strengthened with a further nine South African fellows trained during this period. The African Pediatric Pulmonology program provides a highly successful model, with high retention of graduates in their home countries. The long-term goal is to grow African clinical capacity and strengthen services, research, training, and advocacy for child lung health in Africa.