Modeling approaches and performance for estimating personal exposure to household air pollution: A case study in Kenya.

This study assessed the performance of modeling approaches to estimate personal exposure in Kenyan homes where cooking fuel combustion contributes substantially to household air pollution (HAP). We measured emissions (PM2.5 , black carbon, CO); household air pollution (PM2.5 , CO); personal exposure (PM2.5 , CO); stove use; and behavioral, socioeconomic, and household environmental characteristics (eg, ventilation and kitchen volume). We then applied various modeling approaches: a single-zone model; indirect exposure models, which combine person-location and area-level measurements; and predictive statistical models, including standard linear regression and ensemble machine learning approaches based on a set of predictors such as fuel type, room volume, and others. The single-zone model was reasonably well-correlated with measured kitchen concentrations of PM2.5 (R2  = 0.45) and CO (R2  = 0.45), but lacked precision. The best performing regression model used a combination of survey-based data and physical measurements (R2  = 0.76) and a root mean-squared error of 85 µg/m3 , and the survey-only-based regression model was able to predict PM2.5 exposures with an R2 of 0.51. Of the machine learning algorithms evaluated, extreme gradient boosting performed best, with an R2 of 0.57 and RMSE of 98 µg/m3 .

Pay-as-you-go liquefied petroleum gas supports sustainable clean cooking in Kenyan informal urban settlement during COVID-19 lockdown.

Approximately 2.8 billion people rely on polluting fuels (e.g. wood, kerosene) for cooking. With affordability being a key access barrier to clean cooking fuels, such as liquefied petroleum gas (LPG), pay-as-you-go (PAYG) LPG smart meter technology may help resource-poor households adopt LPG by allowing incremental fuel payments. To understand the potential for PAYG LPG to facilitate clean cooking, objective evaluations of customers' cooking and spending patterns are needed. This study uses novel smart meter data collected between January 2018-June 2020, spanning COVID-19 lockdown, from 426 PAYG LPG customers living in an informal settlement in Nairobi, Kenya to evaluate stove usage (e.g. cooking events/day, cooking event length). Seven semi-structured interviews were conducted in August 2020 to provide context for potential changes in cooking behaviours during lockdown. Using stove monitoring data, objective comparisons of cooking patterns are made with households using purchased 6 kg cylinder LPG in peri-urban Eldoret, Kenya. In Nairobi, 95% of study households continued using PAYG LPG during COVID-19 lockdown, with consumption increasing from 0.97 to 1.22 kg/capita/month. Daily cooking event frequency also increased by 60% (1.07 to 1.72 events/day). In contrast, average days/month using LPG declined by 75% during lockdown (17 to four days) among seven households purchasing 6 kg cylinder LPG in Eldoret. Interviewed customers reported benefits of PAYG LPG beyond fuel affordability, including safety, time savings and cylinder delivery. In the first study assessing PAYG LPG cooking patterns, LPG use was sustained despite a COVID-19 lockdown, illustrating how PAYG smart meter technology may help foster clean cooking access.

Hepatitis A immunisation in persons not previously exposed to hepatitis A.

This review is withdrawn because it is outdated. A new review is to be published by the end of 2019.

A cleaner burning biomass-fuelled cookstove intervention to prevent pneumonia in children under 5 years old in rural Malawi (the Cooking and Pneumonia Study): a cluster randomised controlled trial.

BACKGROUND: WHO estimates exposure to air pollution from cooking with solid fuels is associated with over 4 million premature deaths worldwide every year including half a million children under the age of 5 years from pneumonia. We hypothesised that replacing open fires with cleaner burning biomass-fuelled cookstoves would reduce pneumonia incidence in young children. METHODS: We did a community-level open cluster randomised controlled trial to compare the effects of a cleaner burning biomass-fuelled cookstove intervention to continuation of open fire cooking on pneumonia in children living in two rural districts, Chikhwawa and Karonga, of Malawi. Clusters were randomly allocated to intervention and control groups using a computer-generated randomisation schedule with stratification by site, distance from health centre, and size of cluster. Within clusters, households with a child under the age of 4·5 years were eligible. Intervention households received two biomass-fuelled cookstoves and a solar panel. The primary outcome was WHO Integrated Management of Childhood Illness (IMCI)-defined pneumonia episodes in children under 5 years of age. Efficacy and safety analyses were by intention to treat. The trial is registered with ISRCTN, number ISRCTN59448623. FINDINGS: We enrolled 10 750 children from 8626 households across 150 clusters between Dec 9, 2013, and Feb 28, 2016. 10 543 children from 8470 households contributed 15 991 child-years of follow-up data to the intention-to-treat analysis. The IMCI pneumonia incidence rate in the intervention group was 15·76 (95% CI 14·89-16·63) per 100 child-years and in the control group 15·58 (95% CI 14·72-16·45) per 100 child-years, with an intervention versus control incidence rate ratio (IRR) of 1·01 (95% CI 0·91-1·13; p=0·80). Cooking-related serious adverse events (burns) were seen in 19 children; nine in the intervention and ten (one death) in the control group (IRR 0·91 [95% CI 0·37-2·23]; p=0·83). INTERPRETATION: We found no evidence that an intervention comprising cleaner burning biomass-fuelled cookstoves reduced the risk of pneumonia in young children in rural Malawi. Effective strategies to reduce the adverse health effects of household air pollution are needed. FUNDING: Medical Research Council, UK Department for International Development, and Wellcome Trust.

Development of an Urban Health Impact Assessment methodology: indicating the health equity impacts of urban policies.

Background: An overarching recommendation of the global Commission on Social Determinants of Health was to measure and understand health inequalities and assess the impact of action. In a rapidly urbanising world, now is the time for Urban HIA. This article describes the development of robust and easy-to-use HIA tools to identify and address health inequalities from new urban policies. Rapid reviews and consultation with experts identified existing HIA screening tools and methodologies which were then analyzed against predefined selection criteria. A draft Urban HIA Screening Tool (UrHIST) and Urban HIA methodology (UrHIA) were synthesised. The draft tools were tested and refined using a modified Delphi approach that included input from urban and public health experts, practitioners and policy makers. The outputs were two easy-to-use stand-alone urban HIA tools. The reviews and consultations identified an underpinning conceptual framework. The screening tool is used to determine whether a full HIA is required, or for a brief assessment. Urban health indicators are a readily available and efficient means of identifying variations in the health of populations potentially affected by policies. Indicators are, however, currently underutilised in HIA practice. This may limit the identification of health inequalities by HIA and production of recommendations. The new tools utilise health indicator data more fully. UrHIA also incorporates a hierarchy of evidence for use during impact analysis. The new urban HIA tools have the potential to enhance the rigour of HIAs and improve the identification and amelioration of health inequalities generated by urban policies.

Collecting standardised urban health indicator data at an individual level for adults living in urban areas: methodology from EURO-URHIS 2.

Background: An aim of the EURO-URHIS 2 project was to collect standardised data on urban health indicators (UHIs) relevant to the health of adults resident in European urban areas. This article details development of the survey instruments and methodologies to meet this aim. 32 urban areas from 11 countries conducted the adult surveys. Using a participatory approach, a standardised adult UHI survey questionnaire was developed mainly comprised of previously validated questions, followed by translation and back-translation. An evidence-based survey methodology with extensive training was employed to ensure standardised data collection. Comprehensive UK piloting ensured face validity and investigated the potential for response bias in the surveys. Each urban area distributed 800 questionnaires to age-sex stratified random samples of adults following the survey protocols. Piloting revealed lower response rates in younger males from more deprived areas. Almost 19500 adult UHI questionnaires were returned and entered from participating urban areas. Response rates were generally low but varied across Europe. The participatory approach in development of survey questionnaires and methods using an evidence-based approach and extensive training of partners has ensured comparable UHI data across heterogeneous European contexts. The data provide unique information on health and determinants of health in adults living in European urban areas that could be used to inform urban health policymaking. However, piloting has revealed a concern that non-response bias could lead to under-representation of younger males from more deprived areas. This could affect the generalisability of findings from the adult surveys given the low response rates.

Clean fuels for resource-poor settings: A systematic review of barriers and enablers to adoption and sustained use.

BACKGROUND: Access to, and sustained adoption of, clean household fuels at scale remains an aspirational goal to achieve sufficient reductions in household air pollution (HAP) in order to impact on the substantial global health burden caused by reliance on solid fuels. AIM AND OBJECTIVES: To systematically appraise the current evidence base to identify: (i) which factors enable or limit adoption and sustained use of clean fuels (namely liquefied petroleum gas (LPG), biogas, solar cooking and alcohol fuels) in low- and middle-income countries; (ii) lessons learnt concerning equitable scaling-up of programmes of cleaner cooking fuels in relation to poverty, urban-rural settings and gender. METHODS: A mixed-methods systematic review was conducted using established review methodology and extensive searches of published and grey literature sources. Data extraction and quality appraisal of quantitative, qualitative and case studies meeting inclusion criteria were conducted using standardised methods with reliability checking. FINDINGS: Forty-four studies from Africa, Asia and Latin America met the inclusion criteria (17 on biogas, 12 on LPG, 9 on solar, 6 on alcohol fuels). A broad range of inter-related enabling and limiting factors were identified for all four types of intervention, operating across seven pre-specified domains (i.e. fuel and technology characteristics, household and setting characteristics, knowledge and perceptions, financial, tax and subsidy aspects, market development, regulation, legislation and standards, and programme and policy mechanisms) and multiple levels (i.e. household, community, national). All domains matter and the majority of factors are common to all clean fuels interventions reviewed although some are fuel and technology-specific. All factors should therefore be taken into account and carefully assessed during planning and implementation of any small- and large-scale initiative aiming at promoting clean fuels for household cooking. CONCLUSIONS: Despite limitations in quantity and quality of the evidence this systematic review provides a useful starting point for the design, delivery and evaluation of programmes to ensure more effective adoption and use of LPG, biogas, alcohol fuels and solar cooking. FUNDING: This review was funded by the Department for International Development (DfID) of the United Kingdom. The authors would also like to thank the Evidence for Policy and Practice Information and Co-ordinating Centre (EPPI-Centre) for their technical support.

Does household use of biomass fuel cause lung cancer? A systematic review and evaluation of the evidence for the GBD 2010 study.

BACKGROUND: Around 2.4 billion people use traditional biomass fuels for household cooking or heating. In 2006, the International Agency for Research on Cancer (IARC) concluded emissions from household coal combustion are a Group 1 carcinogen, while those from biomass were categorised as 2A due to epidemiologic limitations. This review updates the epidemiologic evidence and provides risk estimates for the 2010 Global Burden of Disease study. METHODS: Searches were conducted of 10 databases to July 2012 for studies of clinically diagnosed or pathologically confirmed lung cancer associated with household biomass use for cooking and/or heating. FINDINGS: Fourteen eligible studies of biomass cooking or heating were identified: 13 had independent estimates (12 cooking only), all were case-control designs and provided 8221 cases and 11 342 controls. The ORs for lung cancer risk with biomass for cooking and/or heating were OR 1.17 (95% CI 1.01 to 1.37) overall, and 1.15 (95% CI 0.97 to 1.37) for cooking only. Publication bias was not detected, but more than half the studies did not explicitly describe a clean reference category. Sensitivity analyses restricted to studies with adequate adjustment and a clean reference category found ORs of 1.21 (95% CI 1.05 to 1.39) for men (two reports, compiling five studies) and 1.95 (95% CI 1.16 to 3.27) for women (five reports, compiling eight studies). Exposure-response evidence was seen for men, and higher risk for women in developing compared with developed countries, consistent with higher exposures in the former. CONCLUSIONS: There is now stronger evidence for biomass fuel use causing lung cancer, but future studies need better exposure assessment to strengthen exposure-response evidence.

The role of mixed methods in improved cookstove research.

The challenge of promoting access to clean and efficient household energy for cooking and heating is a critical issue facing low- and middle-income countries today. Along with clean fuels, improved cookstoves (ICSs) continue to play an important part in efforts to reduce the 4 million annual premature deaths attributed to household air pollution. Although a range of ICSs are available, there is little empirical evidence on appropriate behavior change approaches to inform adoption and sustained used at scale. Specifically, evaluations using either quantitative or qualitative methods provide an incomplete picture of the challenges in facilitating ICS adoption. This article examines how studies that use the strengths of both these approaches can offer important insights into behavior change in relation to ICS uptake and scale-up. Epistemological approaches, study design frameworks, methods of data collection, analytical approaches, and issues of validity and reliability in the context of mixed methods ICS research are examined, and the article presents an example study design from an evaluation study in Kenya incorporating a nested approach and a convergent case oriented design. The authors discuss the benefits and methodological challenges of mixed-methods approaches in the context of researching behavior change and ICS use recognizing that such methods represent relatively uncharted territory. The authors propose that more published examples are needed to provide frameworks for other researchers seeking to apply mixed methods in this context and suggest a comprehensive research agenda is required that incorporates integrated mixed-methods approaches, to provide best evidence for future scale-up.

Millions dead: how do we know and what does it mean? Methods used in the comparative risk assessment of household air pollution.

In the Comparative Risk Assessment (CRA) done as part of the Global Burden of Disease project (GBD-2010), the global and regional burdens of household air pollution (HAP) due to the use of solid cookfuels, were estimated along with 60+ other risk factors. This article describes how the HAP CRA was framed; how global HAP exposures were modeled; how diseases were judged to have sufficient evidence for inclusion; and how meta-analyses and exposure-response modeling were done to estimate relative risks. We explore relationships with the other air pollution risk factors: ambient air pollution, smoking, and secondhand smoke. We conclude with sensitivity analyses to illustrate some of the major uncertainties and recommendations for future work. We estimate that in 2010 HAP was responsible for 3.9 million premature deaths and ∼4.8% of lost healthy life years (DALYs), ranking it highest among environmental risk factors examined and one of the major risk factors of any type globally.

Determinants of care seeking for children with pneumonia and diarrhea in Guatemala: implications for intervention strategies.

OBJECTIVES: We identified barriers to care seeking for pneumonia and diarrhea among rural Guatemalan children. METHODS: A population-based survey was conducted twice from 2008 to 2009 among 1605 households with children younger than 5 years. A 14-day calendar recorded episodes of carer-reported pneumonia (n = 364) and diarrhea (n = 481), and formal (health services, public, private) and informal (neighbors, traditional, local shops, pharmacies) care seeking. RESULTS: Formal care was sought for nearly half of severe pneumonias but only for 27% within 2 days of onset, with 31% and 18%, respectively, for severe diarrhea. In multivariable analysis, factors independently associated with formal care seeking were knowing the Community Emergency Plan, mother's perception of illness severity, recognition of World Health Organization danger signs, distance from the health center, and having someone to care for family in an emergency. CONCLUSIONS: Proximal factors associated with recognizing need for care were important in determining formal care, and were strongly linked to social determinants. In addition to specific action by the health system with an enhanced community health worker role, a systems approach can help ensure barriers are addressed among poorer and more remote homes.

Estimated health effects from domestic use of gaseous fuels for cooking and heating in high-income, middle-income, and low-income countries: a systematic review and meta-analyses.

BACKGROUND: Exposure to household air pollution from polluting domestic fuel (solid fuel and kerosene) represents a substantial global public health burden and there is an urgent need for rapid transition to clean domestic fuels. Gas for cooking and heating might possibly affect child asthma, wheezing, and respiratory health. The aim of this review was to synthesise the evidence on the health effects of gaseous fuels to inform policies for scalable clean household energy. METHODS: In this systematic review and meta-analysis, we summarised the health effects from cooking or heating with gas compared with polluting fuels (eg, wood or charcoal) and clean energy (eg, electricity and solar energy). We searched PubMed, Scopus, Web of Science, MEDLINE, Cochrane Library (CENTRAL), Environment Complete, GreenFile, Google Scholar, Wanfang DATA, and CNKI for articles published between Dec 16, 2020, and Feb 6, 2021. Studies eligible for inclusion had to compare gas for cooking or heating with polluting fuels (eg, wood or charcoal) or clean energy (eg, electricity or solar energy) and present data for health outcomes in general populations. Studies that reported health outcomes that were exacerbations of existing underlying conditions were excluded. Several of our reviewers were involved in screening studies, data extraction, and quality assessment (including risk of bias) of included studies; 20% of studies were independently screened, extracted and quality assessed by another reviewer. Disagreements were reconciled through discussion with the wider review team. Included studies were appraised for quality using the Liverpool Quality Assessment Tools. Key health outcomes were grouped for meta-analysis and analysed using Cochrane's RevMan software. Primary outcomes were health effects (eg, acute lower respiratory infections) and secondary outcomes were health symptoms (eg, respiratory symptoms such as wheeze, cough, or breathlessness). This study is registered with PROSPERO, CRD42021227092. FINDINGS: 116 studies were included in the meta-analysis (two [2%] randomised controlled trials, 13 [11%] case-control studies, 23 [20%] cohort studies, and 78 [67%] cross-sectional studies), contributing 215 effect estimates for five grouped health outcomes. Compared with polluting fuels, use of gas significantly lowered the risk of pneumonia (OR 0·54, 95% CI 0·38-0·77; p=0·00080), wheeze (OR 0·42, 0·30-0·59; p<0·0001), cough (OR 0·44, 0·32-0·62; p<0·0001), breathlessness (OR 0·40, 0·21-0·76; p=0·0052), chronic obstructive pulmonary disease (OR 0·37, 0·23-0·60; p<0·0001), bronchitis (OR 0·60, 0·43-0·82; p=0·0015), pulmonary function deficit (OR 0·27, 0·17-0·44; p<0·0001), severe respiratory illness or death (OR 0·27, 0·11-0·63; p=0·0024), preterm birth (OR 0·66, 0·45-0·97; p=0·033), and low birth weight (OR 0·70, 0·53-0·93; p=0·015). Non-statistically significant effects were observed for asthma in children (OR 1·04, 0·70-1·55; p=0·84), asthma in adults (OR 0·65, 0·43-1·00; p=0·052), and small for gestational age (OR 1·04, 0·89-1·21; p=0·62). Compared with electricity, use of gas significantly increased risk of pneumonia (OR 1·26, 1·03-1·53; p=0·025) and chronic obstructive pulmonary disease (OR 1·15, 1·06-1·25; p=0·0011), although smaller non-significant effects were observed for higher-quality studies. In addition, a small increased risk of asthma in children was not significant (OR 1·09, 0·99-1·19; p=0·071) and no significant associations were found for adult asthma, wheeze, cough, and breathlessness (p>0·05). A significant decreased risk of bronchitis was observed (OR 0·87, 0·81-0·93; p<0·0001). INTERPRETATION: Switching from polluting fuels to gaseous household fuels could lower health risk and associated morbidity and mortality in resource-poor countries where reliance on polluting fuels is greatest. Although gas fuel use was associated with a slightly higher risk for some health outcomes compared with electricity, gas is an important transitional option for health in countries where access to reliable electricity supply for cooking or heating is not feasible in the near term. FUNDING: WHO.

Burden of headaches, eye irritation and respiratory symptoms among females stacking LPG with polluting cooking fuels: Modelling from peri-urban Cameroon, Ghana & Kenya.

Introduction: Liquefied petroleum gas (LPG) is a clean cooking fuel that emits less household air pollution (HAP) than polluting cooking fuels (e.g. charcoal, wood). While switching from polluting fuels to LPG can reduce HAP and improve health, the impact of 'stacking' (concurrent use of polluting fuels and LPG) on adverse health symptoms (e.g. headaches, eye irritation, cough) among female cooks is uncertain. Methods: Survey data from the CLEAN-Air(Africa) study was collected on cooking patterns and health symptoms over the last 12 months (cough, wheezing, chest tightness, shortness of breath, eye irritation, headaches) from approximately 400 female primary cooks in each of three peri­urban communities in sub-Saharan Africa: Mbalmayo, Cameroon; Obuasi, Ghana; and Eldoret, Kenya. Random effects Poisson regression, adjusted for socioeconomic and health-related covariates, assessed the relationship between primary and secondary cooking fuel type and self-reported health symptoms. Results: Among 1,147 participants, 10 % (n = 118) exclusively cooked with LPG, 45 % (n = 509) stacked LPG and polluting fuels and 45 % (n = 520) exclusively cooked with polluting fuels. Female cooks stacking LPG and polluting fuels had significantly higher odds of shortness of breath (OR 2.16, 95 %CI:1.04-4.48) compared with those exclusively using LPG. In two communities, headache prevalence was 30 % higher among women stacking LPG with polluting fuels (Mbalmayo:82 %; Eldoret:65 %) compared with those exclusively using LPG (Mbalmayo:53 %; Eldoret:33 %). Women stacking LPG and polluting fuels (OR 2.45, 95 %CI:1.29-4.67) had significantly higher odds of eye irritation than women cooking exclusively with LPG. Second-hand smoke exposure was significantly associated with higher odds of chest tightness (OR 1.92, 95 % CI:1.19-3.11), wheezing (OR 1.76, 95 % CI:1.06-2.91) and cough (OR 1.78, 95 %CI:1.13-2.80). Conclusions: In peri­urban sub-Saharan Africa, women exclusively cooking with LPG had lower odds of several health symptoms than those stacking LPG and polluting fuels. Promoting a complete transition to LPG in these communities may likely generate short-term health benefits for primary cooks.

Household concentrations and female and child exposures to air pollution in peri-urban sub-Saharan Africa: measurements from the CLEAN-Air(Africa) study.

BACKGROUND: Relatively clean cooking fuels such as liquefied petroleum gas (LPG) emit less fine particulate matter (PM2·5) and carbon monoxide (CO) than polluting fuels (eg, wood, charcoal). Yet, some clean cooking interventions have not achieved substantial exposure reductions. This study evaluates determinants of between-community variability in exposures to household air pollution (HAP) across sub-Saharan Africa. METHODS: In this measurement study, we recruited households cooking primarily with LPG or exclusively with wood or charcoal in peri-urban Cameroon, Ghana, and Kenya from previously surveyed households. In 2019-20, we conducted monitoring of 24 h PM2·5 and CO kitchen concentrations (n=256) and female cook (n=248) and child (n=124) exposures. PM2·5 measurements used gravimetric and light scattering methods. Stove use monitoring and surveys on cooking characteristics and ambient air pollution exposure (eg, walking time to main road) were also administered. FINDINGS: The mean PM2·5 kitchen concentration was five times higher among households cooking with charcoal than those using LPG in the Kenyan community (297 µg/m3, 95% CI 216-406, vs 61 µg/m3, 49-76), but only 4 µg/m3 higher in the Ghanaian community (56 µg/m3, 45-70, vs 52 µg/m3, 40-68). The mean CO kitchen concentration in charcoal-using households was double the WHO guideline (6·11 parts per million [ppm]) in the Kenyan community (15·81 ppm, 95% CI 8·71-28·72), but below the guideline in the Ghanaian setting (1·77 ppm, 1·04-2·99). In all communities, mean PM2·5 cook exposures only met the WHO interim-1 target (35 µg/m3) among LPG users staying indoors and living more than 10 min walk from a road. INTERPRETATION: Community-level variation in the relative difference in HAP exposures between LPG and polluting cooking fuel users in peri-urban sub-Saharan Africa might be attributed to differences in ambient air pollution levels. Thus, mitigation of indoor and outdoor PM2·5 sources will probably be critical for obtaining significant exposure reductions in rapidly urbanising settings of sub-Saharan Africa. FUNDING: UK National Institute for Health and Care Research.

Legg-Calvé-Perthes disease in the UK: geographic and temporal trends in incidence reflecting differences in degree of deprivation in childhood.

OBJECTIVE: Little is known about Legg-Calvé-Perthes disease, a common childhood precursor to osteoarthritis of the hip. This study was undertaken to analyze the incidence of Legg-Calvé-Perthes disease in the UK, with respect to geographic and temporal trends over a 19-year period. METHODS: The General Practice Research database was analyzed to identify incident cases between 1990 and 2008 in children ages 0-14 years. Incidence rates were calculated by year and by region (National Health Service Strategic Health Authority regions in England, and Scotland, Wales, and Northern Ireland), and the association with regional markers of deprivation examined. RESULTS: Over the 19-year period there was a dramatic decline in Legg-Calvé-Perthes disease incidence, with annual rates among children 0-14 years old declining from 12.2 per 100,000 to 5.7 per 100,000 (P < 0.001). There was also marked geographic variation, with incidence rates in Scotland more than twice those in London (10.39 [95% confidence interval 8.05-13.2] versus 4.6 [95% confidence interval 3.4-6.1] per 100,000 0-14-year-olds). A more rapid decline in incidence was apparent in the Northern regions compared to Southern regions. The quintile with the highest degree of deprivation had the highest disease incidence (rate ratio 1.49 [95% confidence interval 1.10-2.04]) and, with the exception of London, regional incidence showed a strong linear relationship with regional deprivation score (P < 0.01). CONCLUSION: The incidence of Legg-Calvé-Perthes disease in the UK has a strong North-South divide, with a greater disease incidence within the Northern regions of the UK. There was a marked decline in incidence over the study period, which was more marked in Northern areas. The declining incidence, along with the geographic variation, suggests that a major etiologic determinant in Legg-Calvé-Perthes disease is environmental and closely linked to childhood deprivation.

Rising unemployment and increasing spatial health inequalities in England: further extension of the North-South divide.

BACKGROUND: Unemployment negatively affects health. In this study, we quantify the impact of current and rising levels of unemployment on limiting long-term illness (LLTI), mental health problems and mortality in North and South England. METHODS: Excess cases of LLTI and mental health problems in the unemployed were calculated as the difference in the prevalence between the employed and unemployed using data from large population surveys for England. Mortality due to unemployment was calculated using the formula for the population-attributable fraction. RESULTS: Current levels of unemployment were estimated to be causing 1145 deaths per year and a total of 221 020 cases of mental health problems and 275 409 cases of LLTI in England. Rates of mortality, mental health problems and LLTI due to unemployment were distinctively higher in the North compared with the South. Considering hidden unemployment in the calculations considerably increased the proportion of women suffering from ill health due to unemployment. CONCLUSIONS: Our study quantifies the detrimental effect of unemployment on health in England. There is a clear difference between North and South England highlighting the contribution of unemployment to spatial health inequalities. A public health priority should be to (i) prevent unemployment in the first place and (ii) provide support for the unemployed.

Hyperactivity and the psychological burden of Perthes disease: a case-control study.

BACKGROUND: Legg-Calve-Perthes Disease (LCPD) is a childhood precursor to hip osteoarthritis, for which the etiology is unknown. There is a widespread belief that affected individuals are "hyperactive," propagating a theory that such children may have sustained an epiphyseal injury that precipitated the onset of LCPD. This study seeks to quantify the association with hyperactivity, and the wider psychological burden of the disease. METHODS: A case-control study was conducted among 146 cases of LCPD and 142 hospital controls, frequency matched by age and sex. Psychological domains were measured using the Strength and Difficulties Questionnaire. Adjustment was made for age, sex, and socioeconomic deprivation. Results were stratified by the time elapsed since LCPD was diagnosed. RESULTS: Significant associations (P<0.05) existed with the majority of the psychological domains captured by the Strength and Difficulties Questionnaire [odds ratio (OR) for "high" level of difficulties-Emotion OR 3.2, Conduct OR 2.1, Inattention-Hyperactivity OR 2.7, Prosocial Behavior OR 1.9]. Hyperactivity was especially marked among individuals within 2 years of diagnosis (OR 8.6; P<0.001), but not so among individuals over 4 years from diagnosis. Emotional symptoms persisted long after resolution of the active phase of disease. CONCLUSIONS: There was a marked psychological burden among individuals with LCPD, which was most marked amongst individuals with a recent diagnosis. The breadth and inferred temporality of these disturbances may be a function of the disease process, through restriction of activities and disability, or may be a fundamental disease characteristic related directly to disease or to its etiological determinant.

Quantifying the association between psychological distress and low back pain in urban Europe: a secondary analysis of a large cross-sectional study.

OBJECTIVES: This study aims to estimate the prevalence of low back pain (LBP) in Europe and to quantify its associated mental and physical health burdens among adults in European urban areas. DESIGN: This research is a secondary analysis of data from a large multicountry population survey. SETTING: The population survey on which this analysis is based was conducted in 32 European urban areas across 11 countries. PARTICIPANTS: The dataset for this study was collected during the European Urban Health Indicators System 2 survey. There were a total of 19 441 adult respondents but data from 18 028, 50.2% female (9 050) and 49.8% male (8 978), were included in these analyses. PRIMARY AND SECONDARY OUTCOME MEASURES: Being a survey, data on the exposure (LBP) and outcomes were collected simultaneously. The primary outcomes for this study are psychological distress and poor physical health. RESULTS: The overall European prevalence of LBP was 44.6% (43.9-45.3) widely ranging from 33.4% in Norway to 67.7% in Lithuania. After accounting for sex, age, socioeconomic status and formal education, adults in urban Europe suffering LBP had higher odds of psychological distress aOR 1.44 (1.32-1.58) and poor self-rated health aOR 3.54 (3.31-3.80). These associations varied widely between participating countries and cities. CONCLUSION: Prevalence of LBP, and its associations with poor physical and mental health, varies across European urban areas.

What is the current evidence for the relationship between the climate and environmental crises and child marriage? A scoping review.

Environmental crises such as climate change threaten the realisation of sexual and reproductive health and rights. In this scoping review, we examine the evidence for the relationship between environmental crises and child marriage. We conducted a search of Google Scholar, Scopus and MedLine from their origin to 4th June 2021 for both peer-reviewed academic literature and 'grey' literature. A total of 24 relevant articles were identified, including both quantitative and qualitative work. while there are limitations of the current evidence base such as its narrow geographical scope, we find that environmental crises worsen known drivers of child marriage, pushing families to marry their daughters early through loss of assets and opportunities for income generation, displacement of people from their homes, educational disruption, and the creation of settings in which sexual violence and the fear of sexual violence increase. Local socio-cultural contexts such as bride price or dowry practices further shape how these factors affect child marriage. Given many of the areas with the highest current rates of child marriage face the gravest environmental threats, action to tackle child marriage must take account of the link identified in this review.

Did COVID-19 Change the Availability and Use of Clean Energy for Cooking? Evidence From Ghana.

A major part of Ghana's current household energy policy is focused on using a branded cylinder recirculation model (BCRM) to promote the safe use of Liquefied Petroleum Gas (LPG) for primary cooking. The implementation of the BCRM is expected to increase LPG adoption by households to the announced policy goal of 50% of the population by 2030. We investigated the impact of the COVID-19 pandemic on the implementation of the BCRM, availability, and household use of cleaner fuels. This was assessed using existing data on clean fuel use prior to the COVID-19 pandemic. Additional data was collected using questionnaire-based household surveys and qualitative interviews. It was found that the expansion of BCRM was significantly impacted by the COVID-19 pandemic. Planning activities such as baseline data collection and stakeholder engagement were delayed due to the COVID-19 restrictions. Changes in household incomes during the pandemic had the biggest percentage effect on household choice of cooking fuel, causing a regression in some cases, to polluting fuel use. This study provides insights that could be valuable in future understanding of the interactions between pandemic control measures and economic disruptions that may affect household energy choices for cooking.