Asthma symptoms, spirometry and air pollution exposure in schoolchildren in an informal settlement and an affluent area of Nairobi, Kenya.

BACKGROUND: Although 1 billion people live in informal (slum) settlements, the consequences for respiratory health of living in these settlements remain largely unknown. This study investigated whether children living in an informal settlement in Nairobi, Kenya are at increased risk of asthma symptoms. METHODS: Children attending schools in Mukuru (an informal settlement in Nairobi) and a more affluent area (Buruburu) were compared. Questionnaires quantified respiratory symptoms and environmental exposures; spirometry was performed; personal exposure to particulate matter (PM2.5) was estimated. RESULTS: 2373 children participated, 1277 in Mukuru (median age, IQR 11, 9-13 years, 53% girls), and 1096 in Buruburu (10, 8-12 years, 52% girls). Mukuru schoolchildren were from less affluent homes, had greater exposure to pollution sources and PM2.5. When compared with Buruburu schoolchildren, Mukuru schoolchildren had a greater prevalence of symptoms, 'current wheeze' (9.5% vs 6.4%, p=0.007) and 'trouble breathing' (16.3% vs 12.6%, p=0.01), and these symptoms were more severe and problematic. Diagnosed asthma was more common in Buruburu (2.8% vs 1.2%, p=0.004). Spirometry did not differ between Mukuru and Buruburu. Regardless of community, significant adverse associations were observed with self-reported exposure to 'vapours, dusts, gases, fumes', mosquito coil burning, adult smoker(s) in the home, refuse burning near homes and residential proximity to roads. CONCLUSION: Children living in informal settlements are more likely to develop wheezing symptoms consistent with asthma that are more severe but less likely to be diagnosed as asthma. Self-reported but not objectively measured air pollution exposure was associated with increased risk of asthma symptoms.

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

RATIONALE: There are no population-based studies from sub-Saharan Africa describing longitudinal lung function in adults. OBJECTIVES: To 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. METHODS: We 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 RESULTS: We 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. CONCLUSIONS: We 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.

Lung outcomes and related risk factors in patients after SARS-CoV-2 infection: a hospitalised single-centre cohort from Johannesburg, South Africa.

Background: Sequelae post-SARS-CoV-2 infection, including lung and functional impairment, pose a significant challenge post-recovery. We explored the burden and risk factors for post-COVID-19 sequelae in an African population with prevalent comorbidities including tuberculosis (TB) and HIV. Methods: We conducted an observational cohort study on hospitalised adults with confirmed SARS-CoV-2 infection from 20 March to 06 October 2021 at Chris Hani Baragwanath Academic Hospital, South Africa. We collected data on comorbidities, and COVID-19 severity using the World Health Organization (WHO) clinical progression scale. Prospectively, we followed up all participants within 40-days post-discharge to assess body mass index (BMI), COVID-19 symptoms and quality of life using St George's Respiratory Questionnaire (SGRQ), 6-min walking-test (6MWT), and spirometry. A subsequent in-depth visit assessed plethysmography, diffusing capacity for the lung for carbon monoxide (DLCO), and high-resolution chest-CT. Findings: We followed up 111 participants, where 65.8% were female, median age 50.5 years, and predominantly black-African (92.8%). Relevant comorbidities included TB disease (18.9%) and HIV infection (36%). SGRQ total scores were elevated in 78.9%, median 6MWT distance was reduced at 300 m (IQR 210-400), and nearly half (49.5%) exhibited spirometry findings below the lower limit of normal (LLN). In-depth pulmonary assessment for 61 participants revealed abnormalities in total lung capacity (31.6% <80% predicted), DLCO (53.4% <80% predicted), and chest-CT (86.7% abnormal). Significant risk factors for individual abnormal outcomes, adjusted for age and sex, were TB disease, HIV with CD4 <200 cells/mm3, BMI <18.5 kg/m2 and >35 kg/m2, and initial COVID-19 severity. Interpretation: This study demonstrates substantial lung and functional morbidity within the first weeks post-COVID-19, particularly in individuals with pre-existing comorbidities including TB, HIV, and low or high BMI. Chest-CT and DLCO show best early potential at reflecting COVID-19-related pathologies. Funding: The Bavarian State Ministry of Science and Arts.

Characterising sources of PM2·5 exposure for school children with asthma: a personal exposure study across six cities in sub-Saharan Africa.

BACKGROUND: Air pollution is the second largest risk to health in Africa, and children with asthma are particularly susceptible to its effects. Yet, there is a scarcity of air pollution exposure data from cities in sub-Saharan Africa. We aimed to identify potential exposure reduction strategies for school children with asthma living in urban areas in sub-Saharan Africa. METHODS: This personal exposure study was part of the Achieving Control of Asthma in Children in Africa (ACACIA) project. Personal exposure to particulate matter (PM) was monitored in school children in six cities in sub-Saharan Africa (Blantyre, Malawi; Durban, South Africa; Harare, Zimbabwe; Kumasi, Ghana; Lagos, Nigeria; and Moshi, Tanzania). Participants were selected if they were aged 12-16 years and had symptoms of asthma. Monitoring was conducted between June 21, and Nov 26, 2021, from Monday morning (approximately 1000 h) to Friday morning (approximately 1000 h), by use of a bespoke backpack with a small air pollution monitoring unit with an inbuilt Global Positioning System (GPS) data logger. Children filled in a questionnaire detailing potential sources of air pollution during monitoring and exposures were tagged into three different microenvironments (school, commute, and home) with GPS coordinates. Mixed-effects models were used to identify the most important determinants of children's PM2·5 (PM <2·5 µm in diameter) exposure. FINDINGS: 330 children were recruited across 43 schools; of these, 297 had valid monitoring data, and 1109 days of valid data were analysed. Only 227 (20%) of 1109 days monitored were lower than the current WHO 24 h PM2·5 exposure health guideline of 15 µg/m3. Children in Blantyre had the highest PM2·5 exposure (median 41·8 µg/m3), whereas children in Durban (16·0 µg/m3) and Kumasi (17·9 µg/m3) recorded the lowest exposures. Children had significantly higher PM2·5 exposures at school than at home in Kumasi (median 19·6 µg/m3vs 14·2 µg/m3), Lagos (32·0 µg/m3vs 18·0 µg/m3), and Moshi (33·1 µg/m3vs 23·6 µg/m3), while children in the other three cities monitored had significantly higher PM2·5 exposures at home and while commuting than at school (median 48·0 µg/m3 and 43·2 µg/m3vs 32·3 µg/m3 in Blantyre, 20·9 µg/m3 and 16·3 µg/m3vs 11·9 µg/m3 in Durban, and 22·7 µg/m3 and 25·4 µg/m3vs 16·4 µg/m3 in Harare). The mixed-effects model highlighted the following determinants for higher PM2·5 exposure: presence of smokers at home (23·0% higher exposure, 95% CI 10·8-36·4), use of coal or wood for cooking (27·1%, 3·9-56·3), and kerosene lamps for lighting (30·2%, 9·1-55·2). By contrast, 37·2% (95% CI 22·9-48·2) lower PM2·5 exposures were found for children who went to schools with paved grounds compared with those whose school grounds were covered with loose dirt. INTERPRETATION: Our study suggests that the most effective changes to reduce PM2·5 exposures in these cities would be to provide paving in school grounds, increase the use of clean fuel for cooking and light in homes, and discourage smoking within homes. The most efficient way to improve air quality in these cities would require tailored interventions to prioritise different exposure-reduction policies in different cities. FUNDING: UK National Institute for Health and Care Research.

Predictors associated with critical care need and in-hospital mortality among children with laboratory-confirmed COVID-19 infection in a high HIV infection burden region.

Introduction: Despite the extra mortality associated with COVID-19 death globally, there is scant data on COVID-19-related paediatric mortality in Sub-Saharan Africa. We assessed predictors of critical care needs and hospital mortality in South African children with laboratory-confirmed SARS-CoV-2 infection in region with high HIV infection burden. Methods: We conducted a secondary multicentre analysis of the AFREhealth cohort (a multinational, multicentre cohort of paediatric COVID-19 clinical outcomes across six African countries) of children admitted to the Inkosi Albert Luthuli, a quaternary hospital in KwaZulu-Natal, South Africa, with confirmed RT-PCR between March 2020 and December 2020. We constructed multivariable logistic regression to explore factors associated with the need for critical care (high care/ intensive care hospitalisation or oxygen requirement) and cox-proportional hazards models to further assess factors independently associated with in-hospital death. Results: Of the 82 children with PCR-confirmed SARS-CoV-2 infection (mean ± SD age: 4.2 ± 4.4 years), 35(42.7%) were younger than one year, 52(63%) were female and 59(71%) had a pre-existing medical condition. Thirty-seven (45.2%) children required critical care (median (IQR) duration: 7.5 (0.5-13.5) days) and 14(17%) died. Independent factors associated with need for critical care were being younger than 1 year (aPR: 3.02, 95%CI: 1.05-8.66; p = 0.04), having more than one comorbidity (aPR: 2.47, 95%CI: 1.32-4.61; p = 0.004), seizure (aPR: 2.39, 95%CI: 1.56-3.68; p < 0.001) and impaired renal function. Additionally, independent predictors of in-hospital mortality were exposure to HIV infection (aHR: 6.8, 95%CI:1.54-31.71; p = 0.01), requiring invasive ventilation (aHR: 3.59, 95%CI: 1.01-12.16, p = 0.048) and increase blood urea nitrogen (aHR: 1.06, 95%CI: 1.01-1.11; p = 0.017). However, children were less likely to die from COVID-19 if they were primarily admitted to quaternary unit (aHR: 0.23, 95%CI: 0.1-0.86, p = 0.029). Conclusion: We found a relatively high hospital death rate among children with confirmed COVID-19. During COVID-19 waves, a timely referral system and rapid identification of children at risk for critical care needs and death, such as those less than one year and those with comorbidities, could minimize excess mortality, particularly in high HIV-infection burden countries.

Risk factors and determinants of pulmonary function impairments in chronic respiratory diseases in Ethiopia: A hospital-based cross-sectional study

Introduction: Chronic respiratory diseases (CRDs) are diseases of the lung airways and parenchyma. Globally, they are the leading causes of morbidity and mortality. This study aimed to characterize the common CRDs, along with their lung function and possible determinants in symptomatic patients attending Bishoftu General Hospital, Ethiopia. Methods: A cross-sessional study was conducted at the outpatient of Bishoftu Hospital, Ethiopia from June 2019 to March 2020. Consecutive adult patients aged 18 and above with CRDs (≥8 weeks) were recruited. Questionnaires were used to collect data on demographics, symptoms, diagnoses, and putative risk factors. Lung function was measured by spirometry. Result: A total of 170 participants were recruited, the majority 102(60.0%) were female. The mean age was 49 years (SD=16). The most common symptoms were wheezing in the last twelve months 156 (91.8%), cough 138 (81.2%), and severe exertional breathlessness 137 (80.6%). Thirty-nine (22.9%) were either active or passive smokers. Half of the patients (50.3%) were exposed daily to vapors, dust, gases, or fumes and 58 (34.3%) were exposed to biomass smoke. In total, 138 (81.2%) had a positive allergen skin prick test. Chronic bronchitis (49.1%) and asthma (36.1%) were the most common clinical diagnoses. Classification of lung function revealed 23 (15%) normal, 29 (19%) obstructive, 36(23.5%) restrictive and 61(39.9%) mixed patterns. Airflow obstruction was independently associated with increasing age (p<0.05), exertional breathlessness (p<0.001), previous history of asthma (p<0.05), BMI (p<0.05), and doctor-diagnosed chronic obstructive pulmonary disease (p<0.001) and asthma (p<0.05). Conclusion: This study shows a high burden of abnormal lung function in patients attending clinics because of CRDs symptoms. These findings support the critical need for spirometry services to determine lung abnormality in patients with chronic respiratory symptoms.

Dealing with Access to Spirometry in Africa: A Commentary on Challenges and Solutions.

Spirometry is an important tool in the surveillance, epidemiology, diagnosis, and management of respiratory disease, yet its accessibility is currently limited in Africa where the burden of respiratory diseases is amongst the highest globally. The reasons for limited access to spirometry in Africa include poor access to training and skilled technicians, limited availability of equipment, consumables, and technical support, and lack of human and financial resources. The Pan African Thoracic Society, working together with regional African thoracic societies and key research initiatives in Africa, have made progress in training and education, but a lot of work is still needed to meet the challenges faced. Accurately defining these challenges of access to high quality spirometry, development of local, standardised, and context-specific training and quality assurance tools; development of appropriate reference standards and innovative approaches to addressing the challenges of access to equipment, consumables and technical support are needed. Training and research collaborations that include regional thoracic societies, health system leaders, the Pan African Thoracic Society and international role players in the field are key to maximising available intellectual and financial resources. Hence ensuring that access to high quality spirometry measures that are used effectively in tackling the burden of respiratory disease in Africa.

Spirometry: coming of age in Africa.

A personal journey paralleling the growth of spirometry and spirometry training development in Africa http://ow.ly/kgCl3028nQf.