Suzanne L. Pollard

Chronic exposure to biomass fuel is associated with increased carotid artery intima-media thickness and a higher prevalence of atherosclerotic plaque

Background Biomass fuels are used for cooking in the majority of rural households worldwide. While their use is associated with an increased risk of lung diseases and all-cause mortality, the effects on cardiovascular disease (CVD) are not well characterised. Exposure to biomass fuel smoke has been associated with lung-mediated inflammation and oxidative stress, which may increase the risk of atherosclerosis as evaluated by carotid intima-media thickness (CIMT), carotid atherosclerotic plaque prevalence and blood pressure. Methods A cross-sectional study was performed in 266 adults aged ≥35 years in Puno, Peru (3825 m above sea level). We stratified participants by their long-term history of exposure to clean fuel (n=112) or biomass fuel (n=154) and measured 24 h indoor particulate matter (PM2.5) in a random subset (n=84). Participants completed questionnaires and underwent a clinical assessment, laboratory analyses and carotid artery ultrasound. The main outcome measures were CIMT, carotid plaque and blood pressure. Results The groups were similar in age and gender. The biomass fuel group had greater unadjusted mean CIMT (0.66 vs 0.60 mm; p<0.001), carotid plaque prevalence (26% vs 14%; p=0.03), systolic blood pressure (118 vs 111 mm Hg; p<0.001) and median household PM2.5 (280 vs 14 µg/m3; p<0.001). In multivariable regression, the biomass fuel group had greater mean CIMT (mean difference=0.03 mm, 95% CI 0.01 to 0.06; p=0.02), a higher prevalence of carotid plaques (OR=2.6, 95% CI 1.1 to 6.0; p=0.03) and higher systolic blood pressure (mean difference=9.2 mm Hg, 95% CI 5.4 to 13.0; p<0.001). Conclusions Chronic exposure to biomass fuel was associated with increased CIMT, increased prevalence of atherosclerotic plaques and higher blood pressure. These findings identify biomass fuel use as a risk factor for CVD, which may have important global health implications.

25-hydroxy vitamin D levels are associated with childhood asthma in a population-based study in Peru

Vitamin D deficiency may be associated with an increased risk of asthma.

Estimating the herd immunity effect of rotavirus vaccine

INTRODUCTION Diarrhea is one of the leading causes of death in children under 5, and an estimated 39% of these deaths are attributable to rotavirus. Currently two live, oral rotavirus vaccines have been introduced on the market; however, the herd immunity effect associated with rotavirus vaccine has not yet been quantified. The purpose of this meta-analysis was to estimate the herd immunity effects associated with rotavirus vaccines. METHODS We performed a systematic literature review of articles published between 2008 and 2014 that measured the impact of rotavirus vaccine on severe gastroenteritis (GE) morbidity or mortality. We assessed the quality of published studies using a standard protocol and conducted meta-analyses to estimate the herd immunity effect in children less than one year of age across all years presented in the studies. We conducted these analyses separately for studies reporting a rotavirus-specific GE outcome and those reporting an all-cause GE outcome. RESULTS In studies reporting a rotavirus-specific GE outcome, four of five of which were conducted in the United States, the median herd effect across all study years was 22% [19-25%]. In studies reporting an all-cause GE outcome, all of which were conducted in Latin America, the median herd effect was 24.9% [11-30%]. CONCLUSIONS There is evidence that rotavirus vaccination confers a herd immunity effect in children under one year of age in the United States and Latin American countries. Given the high variability in vaccine efficacy across regions, more studies are needed to better examine herd immunity effects in high mortality regions.

Estimating the impact of interventions on cause-specific maternal mortality: a Delphi approach.

BackgroundApproximately 287,000 women die of causes related to pregnancy and childbirth every year. While effective interventions exist to prevent maternal death, high quality impact evaluations for these interventions are often lacking.MethodsWe conducted a Delphi process consisting of three rounds in which we asked maternal health experts to provide effectiveness estimates for 31 intervention-cause of death pairs relating to maternal mortality. Anonymous feedback in the form of medians and histograms for each question was given to experts following the first and second rounds. A diverse panel of 37 experts completed all three rounds, for a final response rate 80.4%.ResultsThis Delphi process produced a total of 31 effectiveness estimates for key maternal interventions on cause-specific maternal mortality. Overall, many interventions had high estimated effectiveness, with the majority of interventions having effectiveness estimates above 70%. Where possible, the estimates of effectiveness of interventions were compared to previous efforts and in general there was strong agreement between the estimates in this exercise as compared to those of earlier efforts.ConclusionsThere are many maternal health interventions with high estimated effectiveness that, with expansion of effective delivery channels, have the potential to have a large impact on reducing maternal mortality worldwide.

Family and Community Influences on Diabetes-Related Dietary Change in a Low-Income Urban Neighborhood

Purpose The purpose of this study is to explore the influence of the social environment, including family and community relationships, on diabetes-related dietary change behaviors in a low-income, predominantly African American community with limited access to healthy foods. Methods Study methods included interviews and focus groups with adults with diabetes and family members of individuals with diabetes in a low-income African American community. In this analysis, interview participants included 11 participants with diabetes, one with prediabetes, and 8 family members or close friends with diabetes. Information from 4 participants with diabetes and 6 with family members with diabetes was included from 6 focus groups. Transcripts were analyzed via thematic iterative coding influenced by social cognitive theory to understand the influence of family and community relationships on dietary change. Results Participants’ social environments strongly influenced diet-related behavioral change. Family members without diabetes provided reinforcements for dietary change for those with diabetes by preparing healthy food and monitoring intake, as well as by adopting dietary changes made by those with diabetes. Family and community members served as sources of observational learning about the potential impacts of diabetes and enhanced behavioral capability for dietary change among people with diabetes by providing dietary advice and strategies for making healthy choices. Conclusions This study demonstrates the ways in which family and community members can influence dietary change in people with diabetes. Interventions targeting diabetes management should incorporate families and communities as sources of information, learning, and support.

Lack of association between chronic exposure to biomass fuel smoke and markers of right ventricular pressure overload at high altitude

BACKGROUND Chronic exposure to biomass fuel smoke has been implicated in the development of pulmonary hypertension and right ventricular pressure/volume overload through activation of inflammation, increase in vascular resistance, and endothelial dysfunction. We sought to compare N-terminal pro-B-type natriuretic peptide (NT-pro-BNP) and echocardiography-derived pulmonary artery systolic pressure (PASP) levels in a high-altitude population-based study in Peru with and without chronic exposure to biomass fuel smoke. METHODS NT-pro-BNP levels were measured in 519 adults (275 with and 244 without chronic exposure to biomass fuel smoke). Participants answered sociodemographics and clinical history questionnaires, underwent a clinical examination and blood testing for cardiopulmonary biomarkers. PASP was measured in a subgroup of 153 (31%) subjects. RESULTS The study group consisted of 280 men (54%) and 239 women (46%). Average age was 56 years and average body mass index was 27 kg/m(2). In multivariable analysis, there was no association between chronic exposure to biomass fuel smoke and NT-pro-BNP (P = .31) or PASP (P = .31). In the subgroup in which both NT-pro-BNP levels and PASP were measured, there was strong evidence of an association between these two variables (ρ = 0.24, 95% CI 0.09-0.39; P = .003). We found that age, high sensitivity C-reactive protein, being male, and systolic blood pressure were positively associated with NT-pro-BNP levels whereas body mass index, low-density/high-density lipoprotein ratio, and Homeostasis Model of Assessment-Insulin Resistance were negatively associated (all P ≤ .02). CONCLUSIONS In this population-based study in a high-altitude setting, neither NT-pro-BNP levels nor echocardiography-derived PASP were associated with chronic exposure to biomass fuel smoke.

Association Between Serum 25-Hydroxy Vitamin D Levels and Blood Pressure Among Adolescents in Two Resource-Limited Settings in Peru

INTRODUCTION Serum 25-hydroxyvitamin D (25OHD) deficiency (<50 nmol/l or 20 ng/ml) has been associated with increased blood pressure (BP) in observational studies. A paucity of data on this relationship is available in Latin American or child populations. This study investigates the association between 25OHD levels and BP in adolescents at risk for vitamin D deficiency in 2 Peruvian settings. METHODS In a population-based study of 1,441 Peruvian adolescents aged 13-15 years, 1,074 (75%) provided a serum blood sample for 25OHD analysis and BP measurements. Relationships between 25OHD and BP metrics were assessed using multiple linear regressions, adjusted for anthropometrics and sociodemographic factors. RESULTS 25OHD deficiency was associated with an elevated diastolic BP (DBP) (1.09 mm Hg increase, 95% confidence interval: 0.04 to 2.14; P = 0.04) compared to nondeficient adolescents. Systolic BP (SBP) trended to increase with vitamin D deficiency (1.30 mm Hg increase, 95% confidence interval: -0.13 to 2.72; P = 0.08). Mean arterial pressure (MAP) was also greater in adolescents with 25OHD (1.16 mm Hg increase, 95% confidence interval: 0.10 to 2.22; P = 0.03). SBP was found to demonstrate a U-shaped relationship with 25OHD, while DBP and MAP demonstrated inverse J-shaped relationships with serum 25OHD status. The association between 25OHD deficiency and BP was not different across study sites (all P ≥ 0.19). DISCUSSION Adolescents deficient in 25OHD demonstrated increased DBP and MAP and a trend toward increased SBP, when compared to nondeficient subjects. 25OHD deficiency early in life was associated with elevated BP metrics, which may predispose risk of hypertension later in adulthood.

Managing threats to respiratory health in urban slums

More than half the world’s population lives in urban areas, and an estimated 863 million people currently live in urban slums. Although urbanisation is usually coupled with economic development, rural-to-urban migration can result in negative implications for respiratory health. Slum residents who live in informal settlements and who commonly have inadequate access to health services are at a particularly high risk of being aff ected by the dual burden of infectious and non-communicable respiratory diseases over the course of their lives. These diseases include pneumonia in early life; asthma beginning in childhood; and tuberculosis, COPD, and restrictive lung diseases during adulthood. Threats to respiratory health include infections due to poor housing quality and overcrowding; ambient, traffi c-related, and household air pollution; tobacco and second-hand smoke; occupational exposures; allergenic sensitisation; micronutrient defi ciencies; poor and inadequate diet; and a sedentary lifestyle (appendix). Here, we present three examples to illustrate the threats to respiratory health confronted by people living in slums. India has the second largest urban population in the world with 377 million people living in cities, which is projected to double by 2041. Among them, 65 million people (17%) live in overcrowded slums with poor amenities, often adjacent to large open drains and waste disposal sites, predisposing slum residents to an increased risk of infectious diseases. Additionally, half the adult population uses smokeless tobacco, one in three smoke, and one in six adults living in slums in India use alcohol routinely. Low physical activity coupled with low intake of fruits and vegetables has led to an increased prevalence of obesity in urban slums compared with the rural population. The burden of respiratory diseases caused by air pollution exceeds that due to tuberculosis, ischaemic heart disease, all cancers, and road accidents combined. Household air pollution is responsible for between 4·2% and 6·1% of total morbidity in India, aff ecting two-thirds of women and children. Nearly half of slum residents have respiratory diseases and spend more than 10% of their household income on associated treatment. Peru has witnessed rapid urbanisation over the past fi ve decades. By 2015, 23·5 million (76%) of the population lived in urban areas, and in 2014, 8·2 million (36% of the urban population) lived in slums. Periurban communities have had substantial improvements in basic infrastructure over the past two decades. Chronic diseases are now responsible for approximately 87 120 (66%) of deaths in Peru, and around 16% of adults are obese;—the profi le of respiratory diseases away from infectious diseases and towards chronic diseases refl ects this transition. Pneumonia is still the leading cause of death in children in Peru, and tuberculosis is an important cause of morbidity and mortality. The capital city, Lima, has a high prevalence of childhood asthma by contrast with a low reported prevalence in rural settings. These diff erences probably result from high levels of allergic sensitisation from poor living conditions and traffi c-related pollution. Moreover, chronic bronchitis is as prevalent in periurban settings as in rural settings in Peru. COPD has been linked to the history of both tuberculosis and asthma in urban slums, indicating that respiratory conditions from early life can interact to aff ect risk in later life. Findings from epidemiological studies have shown a low prevalence of daily tobacco smoking in resourcepoor settings, representing a potential opportunity for both primary and secondary prevention following WHO’s MPOWER Tobacco Free Initiative measures. Uganda is an example of a country in the early stages of slum development, and off ers potential targets for early intervention. Uganda has high rates of urbanisation and fertility, which when compounded with high costs of land and a shortage of tenure, have led to a substantial proportion of the urban population living in slum conditions. Of 5 million urban residents in Uganda, around 2 million (60%) live in slums. Slum residents face unique risk factors for acute respiratory disease. The prevalence of COPD in adults and the prevalence of acute respiratory infections among children is highest in households exposed to household air pollution from biomass, which is disproportionately used in slums. A shortage of waste management and water-treatment systems (only around 420 000 [14%] of slum residents have access to piped water), high rates of malnutrition, and large household sizes are additional risk factors for acute For more on WHO’s Tobacco Free Initiative see http://www. who.int/tobacco/mpower/en See Online for appendix Lancet Respir Med 2016

An evaluation of the Fondo de Inclusión Social Energético program to promote access to liquefied petroleum gas in Peru

Introduction Over 80% of rural households in Peru use solid fuels as their primary source of domestic energy, which contributes to several health problems. In 2016, 6.7 million Peruvians were living in rural areas. The Fondo de Inclusión Social Energético (FISE) LPG Promotion Program, which began in 2012 and is housed under the Ministry of Energy and Mining, is a government-sponsored initiative aimed at reducing use of solid fuels by increasing access to clean fuel for cooking to poor Peruvian households. Methods We conducted a mixed methods study incorporating data from publicly available records and reports, a community survey of 375 households in Puno (the province with the largest number of FISE beneficiary households), and in-depth interviews with community members and key stakeholders. We used the Reach, Effectiveness - Adoption, Implementation, Maintenance (RE-AIM) framework to guide our data collection and analysis efforts. In a sample of 95 households, we also measured 48-hour area concentrations and personal exposures to fine particulate matter (PM2.5). Results The FISE LPG promotion program has achieved high geographical reach; the program is currently serving households in 100% of districts in Peru. Households with access to electricity may be participating at a higher level than households without electricity because the program is implemented primarily by electricity distributors. In a sample of 95 households, FISE beneficiaries experienced a reduction in kitchen concentrations of PM2.5; however, there were no differences in personal exposures, and both kitchen and personal exposures were above the WHO intermediate target for indoor air quality. Among the 375 households surveyed, stove stacking with biomass fuels was reported in more than 95% of both beneficiary and non-beneficiary households, with fewer than 5% reporting exclusive use. In-depth interviews suggest that the complexity of enrollment process and access to LPG distribution points may be key barriers to participating in FISE. Conclusion The FISE LPG Program has achieved high reach and its targeted subsidy and surcharge-based financing structure represent a potentially feasible and sustainable model for other government programs. However, the prevalence of stove stacking among FISE beneficiaries remains high. There is a need for improved communication channels between program implementers and beneficiaries. FISE should also consider expanding the mobile LPG network and community delivery service to reduce physical barriers and indirect costs of LPG acquisition. Finally, increasing the value of LPG vouchers to completely cover one or two tanks a month, or alternatively, introducing behavior change strategies to reduce monthly LPG usage, may facilitate the transition to exclusive LPG use.

Vitamin D and COPD: who benefits from supplementation?

www.thelancet.com/respiratory Vol 3 February 2015 89 could potentially be averted with intermittent use. Indeed, in this study, the estimated cumulative dose of inhaled corticosteroid use was substantially lower in the intermittent group (24·5 mg) than in the regular group (116·8 mg). Moreover, fewer patients in the as-needed group than in the regular group had nasopharyngitis and oropharyngeal pain. The costs were not measured, and should be assessed at a broader level than only the costs of the inhalers and also include health-care use. Side-eff ects and costs need to be weighed against the benefi ts in terms of asthma control and quality of life. Some people will argue that the diff erence between as-needed and regular use on the primary composite endpoint in this trial is ambiguous since it was driven by nocturnal awakenings only. However, since all the secondary endpoints also signifi cantly favoured regular use of the treatment, we believe the results clearly support the regular use of combined inhaled corticosteroids and longacting β2 agonists in adult patients with moderate and higher severity asthma. This approach is in line with existing guidelines but has now been substantiated.