Cooking fuel and respiratory symptoms among people living with HIV in rural Uganda

Association between long-term exposure to fine particulate matter and its chemical constituents and premature death in individuals living with HIV/AIDS

Long-term exposure to fine particulate matter (PM2.5) is associated with an increased total mortality. However, the association of PM2.5 with mortality in people living with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS, PLWHA) and the relationship between its constituents and adverse outcomes remain unknown. In this cohort study, 28,140 PLWHA were recruited from the HIV/AIDS Comprehensive Response Information Management System of the Hubei Provincial Centre for Disease Control and Prevention in China between 2001 and 2020. The annual PM2.5 chemical composition data, including sulfate (SO42-), nitrate (NO3-), ammonium (NH4+), black carbon (BC), and organic matter (OM), was extracted from the Tracking Air Pollution (TAP) dataset in China. A Cox proportional hazard model with time-varying exposure and time-to-event quantile-based generalized (g) computation was used to assess the associations between PM2.5 chemical constituents, and mortality in PLWHA. A multivariate Cox proportional hazard model estimated an excess hazard ratio (eHR) of 0.32% [95% confidence interval (CI): (0.01%, 0.64%)] for AIDS-related death (ARD), associated with 1 μg/m3 rise in PM2.5 exposure. An increase of 1 μg/m3 in NH4+ was associated with 5.13% [95% CI: (2.89%, 7.43%)] and 2.97% [95% CI: (1.52%, 4.44%)] increase in the risk of ARD and all-cause deaths (ACD), respectively. When estimated using survival-based quantile g-computation, the eHR for ARD with a joint change in a decile increase in all five components was 6.10% [95% CI: 3.77%, 8.48%)]. Long-term exposure to PM2.5 chemical composition, particularly NH4+ increased the risk of death in PLWHA. This study provides epidemiological evidence that SO42- and NH4+ increased the risk of ARD and that NH4+ increased the risk of ACD in PLWHA. Multi-constituent analyses further suggested that NH4+ may be a key component in increasing the risk of premature death in patients with HIV/AIDS. Individuals aged ≥65 with HIV/AIDS are more vulnerable to SO42-, and consequent ACD.

Is there still a social gradient in respiratory symptoms? A population-based Nordic EpiLung-study

BACKGROUND

Respiratory symptoms are a common public health issue that can partly be attributed to preventable risk factors, such as tobacco smoking and occupational exposure, which are more common in individuals with lower socioeconomic status.

OBJECTIVE

Our aim was to evaluate the social gradient in respiratory symptoms in Nordic countries.

METHODS

This study included participants aged 30-65 years from five cross-sectional population-based questionnaire surveys in 2016 in Finland and Sweden (N = 25,423) and in 2017-2019 in Norway (N = 27,107). Occupational skill levels 1 and 2 (occupations requiring compulsory education) were combined and compared to skill levels 3 and 4 (occupations requiring upper secondary and tertiary education). Meta-analysis was conducted to obtain pooled age- and sex adjusted odds ratios (aORs) of associations between occupational skill and the respiratory symptoms including recurrent wheeze, dyspnoea, and productive cough.

RESULTS

In the meta-analysis, recurrent wheeze, dyspnoea, and productive cough showed a social gradient. The participants with occupational skill 1 and 2 had higher risk for recurrent wheeze (aOR 1.78, 95% CI 1.34-2.22) and dyspnoea (aOR 1.59, 95% CI 1.29-1.90) compared to occupational skill 3 and 4 in Sweden and Finland. Similarly increased risk was observed for combined assessment of dyspnoea and wheeze (aOR 1.05, 95% CI 1.03-1.07) in Norway. In a meta-analysis including all three countries, the aOR for productive cough was 1.31 95% CI 1.07-1.56.

CONCLUSIONS

Occupations with lower, compared to higher, skill levels were associated with an increased risk of recurrent wheeze, dyspnoea, and productive cough.

Health risks associated with the production and usage of charcoal: a systematic review

Charcoal production and utilisation are linked to various health issues and occupational hazards. However, to our knowledge, no systematic review has primarily focused on the health implications of charcoal production and its use while distinguishing charcoal from other solid fuels such as wood and coal.

OBJECTIVES

This systematic review presents a synthesis of the evidence on the health risks associated with producing and using charcoal across the world.

DESIGN

Systematic review using a systematic narrative synthesis approach.

DATA SOURCES

MEDLINE (through Ovid interface), CINAHL, Embase, Web of Science, PsycINFO, Cochrane Library and SCOPUS, from inception to 26 February 2021.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Peer-reviewed journal articles reporting empirical findings on the associations between charcoal usage/production and health parameters.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed the quality of primary studies.

RESULTS

Our findings showed that charcoal production and usage are linked with specific adverse health outcomes, including respiratory diseases (n=21), cardiorespiratory and neurological diseases (n=1), cancer (n=3), DNA damage (n=3), carbon monoxide (CO) poisoning (n=2), physical injury (n=2), sick house syndrome (n=1), unintentional weight loss and body mass index (BMI) reduction (n=2), increase in blood pressure (n=1) and CO death (n=1). Among the included articles that reported respiratory diseases (n=21), there was one case of asthma and tuberculosis and two cases of chronic obstructive pulmonary disease.

CONCLUSIONS

This review links charcoal production/usage and some associated human health risks. These include respiratory diseases and other non-respiratory illnesses such as sick-building syndrome, cardiovascular diseases, DNA damage, CO poisoning and death, unintentional weight loss and BMI reduction, and physical injuries.

Exposure to Wood Smoke and Associated Health Effects in Sub-Saharan Africa: A Systematic Review

Background

Observational studies suggest that exposure to wood smoke is associated with a variety of adverse health effects in humans.

Objective

We aimed to summarise evidence from sub-Saharan Africa on levels of exposure to pollutants in wood smoke and the association between such exposures and adverse health outcomes.

Methods

PubMed and Google scholar databases were searched for original articles reporting personal exposure levels to pollutants or health outcomes associated with wood smoke exposure in Sub-Saharan African population.

Results

Mean personal PM_2.5 and carbon monoxide levels in the studies ranged from 26.3 ± 1.48 μg/m³ to 1574 ± 287μg/m³ and from 0.64 ± 2.12 ppm to 22 ± 2.4 ppm, respectively. All the reported personal PM_2.5 exposure levels were higher than the World Health Organization's Air Quality Guideline (AQG) for 24-hour mean exposure. Use of wood fuels in domestic cooking is the major source of wood smoke exposure in this population. Occupational exposure to wood smoke included the use of wood fuels in bakery, fish drying, cassava processing and charcoal production. Females were exposed to higher levels of these pollutants than males of the same age range. Major determinants for higher exposure to wood smoke in SSA included use of unprocessed firewood, female gender and occupational exposure. We recorded strong and consistent associations between exposure to wood smoke and respiratory diseases including acute respiratory illness and impaired lung function. Positive associations were reported for increased blood pressure, low birth weight, oesophageal cancer, sick building syndrome, non-syndromic cleft lip and/or cleft palate and under-five mortality.

Conclusion

There is high level of exposure to wood smoke in SSA and this exposure is associated with a number of adverse health effects. There is urgent need for aggressive programs to reduce wood smoke exposure in this population.

Prevalence and correlates of Alzheimer's disease and related dementias in rural Uganda: cross-sectional, population-based study

Background

There is a paucity of data on the prevalence and correlates of Alzheimer’s disease and related dementias in sub-Saharan Africa. The aim of the study was to estimate the prevalence and correlates of Alzheimer’s disease and related dementias in rural Uganda.

Methods

We conducted a cross-sectional, population-based study in a rural region of southwestern Uganda. The Brief Community Screening Instrument for Dementia was administered to a multi-stage area probability sample of 400 people aged 60 years and over. Multivariable logistic regression was used to estimate correlates of probable dementia.

Results

Overall, 80 (20%) of the sample screened positive for dementia. On multivariable regression, we estimated the following correlates of probable dementia: age (adjusted odds ratio [AOR], 1.02 per year; 95% confidence interval [CI], 1.10–1.03, p<0.001), having some formal education (AOR, 0.57; 95% CI, 0.41–0.81, p = 0.001), exercise (AOR, 0.44; 95% CI, 0.27–0.72, p = 0.001), and having a ventilated kitchen (AOR, 0.43; (95% CI, 0.24–0.77, p = 0.001).

Conclusions

In this population-based sample of older-age adults in rural Uganda, nearly one-fifth screened positive for dementia.

Brief Report: Systemic Inflammation, Immune Activation, and Impaired Lung Function Among People Living With HIV in Rural Uganda

BACKGROUND

Although both chronic lung disease and HIV are inflammatory diseases common in sub-Saharan Africa, the relationship between systemic inflammation and lung function among people living with HIV (PLWH) in sub-Saharan Africa is not well described.

METHODS

We measured lung function (using spirometry) and serum high sensitivity C-reactive protein, interleukin 6 (IL-6), soluble CD14 (sCD14), and soluble CD163 (sCD163) in 125 PLWH on stable antiretroviral therapy (ART) and 109 age- and sex-similar HIV-uninfected control subjects in rural Uganda. We modeled the relationship between lung function and systemic inflammation using linear regression, stratified by HIV serostatus, controlled for age, sex, height, tobacco, and biomass exposure.

RESULTS

Half of subjects [46% (107/234)] were women, and the median age was 52 years (interquartile range: 48-55). Most PLWH [92% (115/125)] were virologically suppressed on first-line ART. Median CD4 count was 472 cells/mm. In multivariable linear regression models stratified by HIV serostatus, an interquartile range increase in IL-6 and sCD163 were each inversely associated with lung function (mL, 95% confidence interval) among PLWH [IL-6: forced expiratory volume in 1 second (FEV1) -18.1 (-29.1 to -7.1), forced vital capacity (FVC) -17.1 (-28.2 to -5.9); sCD163: FVC -14.3 (-26.9 to -1.7)]. High sensitivity C-reactive protein (>3 vs. <1 mg/L) was inversely associated with lung function among both PLWH and HIV-uninfected control subjects [PLWH: FEV1 -39.3 (-61.7 to -16.9), FVC -44.0 (-48.4 to -6.4); HIV-uninfected: FEV1 -37.9 (-63.2 to -12.6), FVC -58.0 (-88.4 to -27.5)]. sCD14 was not associated with lung function, and all interaction terms were insignificant.

CONCLUSIONS

Macrophage activation and systemic inflammation are associated with lower lung function among PLWH on stable ART in rural Uganda. Future work should focus on underlying mechanisms and public health implications.

Personal carbon monoxide exposure, respiratory symptoms, and the potentially modifying roles of sex and HIV infection in rural Uganda: a cohort study

BACKGROUND

Most of the global burden of pollution-related morbidity and mortality is believed to occur in resource-limited settings, where HIV serostatus and sex may influence the relationship between air pollution exposure and respiratory morbidity. The lack of air quality monitoring networks in these settings limits progress in measuring global disparities in pollution-related health. Personal carbon monoxide monitoring may identify sub-populations at heightened risk for air pollution-associated respiratory morbidity in regions of the world where the financial cost of air quality monitoring networks is prohibitive.

METHODS

From September 2015 through May 2017, we measured 48-h ambulatory carbon monoxide (CO) exposure in a longitudinal cohort of HIV-infected and uninfected adults in rural southwestern Uganda. We fit generalized mixed effects models to identify correlates of CO exposure exceeding international air quality thresholds, quantify the relationship between CO exposure and respiratory symptoms, and explore potential effect modification by sex and HIV serostatus.

RESULTS

Two hundred and sixty study participants completed 419 sampling periods. Personal CO exposure exceeded international thresholds for 50 (19%) participants. In covariate-adjusted models, living in a home where charcoal was the main cooking fuel was associated with CO exposure exceeding international thresholds (adjusted odds ratio [AOR] 11.3, 95% confidence interval [95%CI] 4.7-27.4). In sex-stratified models, higher CO exposure was associated with increased odds of respiratory symptoms among women (AOR 3.3, 95%CI 1.1-10.0) but not men (AOR 1.3, 95%CI 0.4-4.4). In HIV-stratified models, higher CO exposure was associated with increased odds of respiratory symptoms among HIV-infected (AOR 2.5, 95%CI 1.01-6.0) but not HIV-uninfected (AOR 1.4, 95%CI 0.1-14.4) participants.

CONCLUSIONS

In a cohort in rural Uganda, personal CO exposure frequently exceeded international thresholds, correlated with biomass exposure, and was associated with respiratory symptoms among women and people living with HIV. Our results provide support for the use of ambulatory CO monitoring as a low-cost, feasible method to identify subgroups with heightened vulnerability to pollution-related respiratory morbidity in resource-limited settings and identify subgroups that may have increased susceptibility to pollution-associated respiratory morbidity.

Association of Gut Intestinal Integrity and Inflammation with Insulin Resistance in Adults Living with HIV in Uganda

We conducted a cross-sectional study of 148 HIV+ on HIV antiretroviral therapy and 149 HIV- adults in Mbarara, Uganda, to estimate the association between HIV infection and homeostasis model assessment of insulin resistance (HOMA-IR) using multivariable regression analysis. In addition, we evaluated whether intestinal fatty acid-binding protein (I-FABP), monocyte activation markers soluble (s)CD14 and sCD163, and proinflammatory cytokine interleukin 6 (IL-6) mediated this association. HOMA-IR was greater among HIV+ than HIV- adults [median (interquartile range): 1.3 (0.7-2.5) vs. 0.9 (0.5-2.4); p = 0.008]. In models adjusted for sociodemographic variables, diet, hypertension, and smoking history, HIV infection was associated with 37% [95% confidence intervals (95% CIs): 5-77] greater HOMA-IR compared with HIV- participants. The magnitude of association was greater when I-FABP was included as a covariate although the additive effect was modest (40% CI: 8-82). By contrast adding sCD14 to the model was associated with greater HOMA-IR (59%; 95% CI: 21-109) among HIV+ participants compared with HIV- participants. Among HIV+ participants, greater CD4 nadir was non-significantly associated with greater HOMA-IR (22%; 95% CI: -2 to 52). Each 5-unit increase in body mass index (BMI; 49% greater HOMA-IR; 95% CI: 18-87) and female sex (71%; 95% CI: 17-150) remained associated in adjusted models. In this study of mainly normal-weight Ugandan adults, HIV infection, female sex, and greater BMI were all associated with greater insulin resistance (IR). This association was strengthened modestly after adjustment for sCD14, suggesting possible distinct immune pathways to IR that are independent of HIV or related to inflammatory changes occurring on HIV treatment.

Prevalence and correlates of chronic obstructive pulmonary disease and chronic respiratory symptoms in rural southwestern Uganda: a cross-sectional, population-based study

Background

The global burden of chronic obstructive pulmonary disease (COPD) disproportionately affects resource-limited settings such as sub-Saharan Africa (SSA), but population-based prevalence estimates in SSA are rare. We aimed to estimate the population prevalence of COPD and chronic respiratory symptoms in rural southwestern Uganda.

Methods

Adults at least 18 years of age who participated in a population-wide census in rural southwestern Uganda completed respiratory questionnaires and lung function testing with bronchodilator challenge at health screening events in June 2015. We defined COPD as post-bronchodilator forced expiratory volume in one second to forced vital capacity ratio less than the lower limit of normal. We fit multivariable linear and log binomial regression models to estimate correlates of abnormal lung function and respiratory symptoms, respectively. We included inverse probability of sampling weights in models to facilitate population-level estimates.

Results

Forty-six percent of census participants (843/1814) completed respiratory questionnaires and spirometry, of which 565 (67%) met acceptability standards. COPD and respiratory symptom population prevalence were 2% (95% confidence interval (CI)  = 1%-3%) and 30% (95% CI = 25%-36%), respectively. Respiratory symptoms were more prevalent and lung function was lower among women and ever-smokers (P < 0.05). HIV serostatus was associated with neither respiratory symptoms nor lung function.

Conclusions

COPD population prevalence was low despite prevalent respiratory symptoms. This work adds to the growing body of literature depicting lower-than-expected COPD prevalence estimates in SSA and raises questions about whether the high respiratory symptom burden in rural southwestern Uganda represents underlying structural lung disease not identified by screening spirometry.

Burden of Acute Respiratory Infections Among Under-Five Children in Relation to Household Wealth and Socioeconomic Status in Bangladesh

Acute respiratory infections (ARIs), as a group of diseases and symptoms, are a leading cause of morbidity and mortality among under-five children in tropical countries like Bangladesh. Currently, no clear evidence has been published on the prevalence and socioeconomic correlates of ARIs in Bangladesh. In this regard, we carried out this study with the aim of assessing the prevalence and the socioeconomic predictors of ARIs among children aged 0⁻59 months, with a special focus on socioeconomic status and wealth-related indicators. Cross-sectional data on 32,998 mother-child (singleton) pairs were collected from six rounds of Bangladesh Demographic and Health Surveys (BDHS 1997⁻2014). The outcome variable were presence of the common symptoms of ARIs, fever and dyspnea, during the previous two weeks, which were measured based on mothers' reports about the symptoms of these conditions. Explanatory variables included maternal demographic and socioeconomic factors such as age, education, occupation, wealth quintile, and child's age and sex. The prevalence and predictors of ARIs were measured using descriptive and multivariate regression methods. The prevalence of both fever (31.00% in 1997 vs. 36.76% in 2014) and dyspnea (39.27% in 1997 vs. 43.27% in 2014) has increased gradually since 1997, and tended to be higher in households in the lower wealth quintiles. Multivariable analysis revealed that higher maternal educational status, access to improved water and sanitation facilities, and living in households in higher wealth quintiles had protective effects against both fever and dyspnea. Findings suggested a significantly negative association between lacking access to improved water and sanitation and use of biomass fuel with ARI symptoms. However, no sex difference was observed in these associations. Based on the findings, childhood ARI prevention strategies should address the risk factors stemming from parental socioeconomic marginalisation, household water and sanitation poverty, and use of unclean fuel.