Food environments and obesity: A geospatial analysis of the South Asia Biobank, income and sex inequalities.

INTRODUCTION: In low-middle income countries (LMICs) the role of food environments on obesity has been understudied. We address this gap by 1) examining the effect of food environments on adults' body size (BMI, waist circumference) and obesity; 2) measuring the heterogeneity of such effects by income and sex. METHODS: This cross-sectional study analysed South Asia Biobank surveillance and environment mapping data for 12,167 adults collected between 2018 and 2020 from 33 surveillance sites in Bangladesh and Sri Lanka. Individual-level data (demographic, socio-economic, and health characteristics) were combined with exposure to healthy and unhealthy food environments measured with geolocations of food outlets (obtained through ground-truth surveys) within 300 m buffer zones around participants' homes. Multivariate regression models were used to assess association of exposure to healthy and unhealthy food environments on waist circumference, BMI, and probability of obesity for the total sample and stratified by sex and income. FINDINGS: The presence of a higher share of supermarkets in the neighbourhood was associated with a reduction in body size (BMI, ß = - 3∙23; p < 0∙0001, and waist circumference, ß = -5∙99; p = 0∙0212) and obesity (Average Marginal Effect (AME): -0∙18; p = 0∙0009). High share of fast-food restaurants in the neighbourhood was not significantly associated with body size, but it significantly increased the probability of obesity measured by BMI (AME: 0∙09; p = 0∙0234) and waist circumference (AME: 0∙21; p = 0∙0021). These effects were stronger among females and low-income individuals. INTERPRETATION: The results suggest the availability of fast-food outlets influences obesity, especially among female and lower-income groups. The availability of supermarkets is associated with reduced body size and obesity, but their effects do not outweigh the role of fast-food outlets. Policies should target food environments to promote better diets and reduce obesity.

Defining hypoxaemia from pulse oximeter measurements of oxygen saturation in well children at low altitude in Bangladesh: an observational study.

BACKGROUND: WHO defines hypoxaemia, a low peripheral arterial oxyhaemoglobin saturation (SpO2), as <90%. Although hypoxaemia is an important risk factor for mortality of children with respiratory infections, the optimal SpO2 threshold for defining hypoxaemia is uncertain in low-income and middle-income countries (LMICs). We derived a SpO2 threshold for hypoxaemia from well children in Bangladesh residing at low altitude. METHODS: We prospectively enrolled well, children aged 3-35 months participating in a pneumococcal vaccine evaluation in Sylhet district, Bangladesh between June and August 2017. Trained health workers conducting community surveillance measured the SpO2 of children using a Masimo Rad-5 pulse oximeter with a wrap sensor. We used standard summary statistics to evaluate the SpO2 distribution, including whether the distribution differed by age or sex. We considered the 2.5th, 5th and 10th percentiles of SpO2 as possible lower thresholds for hypoxaemia. RESULTS: Our primary analytical sample included 1470 children (mean age 18.6±9.5 months). Median SpO2 was 98% (IQR 96%-99%), and the 2.5th, 5th and 10th percentile SpO2 was 91%, 92% and 94%. No child had a SpO2 <90%. Children 3-11 months had a lower median SpO2 (97%) than 12-23 months (98%) and 24-35 months (98%) (p=0.039). The SpO2 distribution did not differ by sex (p=0.959). CONCLUSION: A SpO2 threshold for hypoxaemia derived from the 2.5th, 5th or 10th percentile of well children is higher than <90%. If a higher threshold than <90% is adopted into LMIC care algorithms then decision-making using SpO2 must also consider the child's clinical status to minimise misclassification of well children as hypoxaemic. Younger children in lower altitude LMICs may require a different threshold for hypoxaemia than older children. Evaluating the mortality risk of sick children using higher SpO2 thresholds for hypoxaemia is a key next step.

Effectiveness of the 10-valent pneumococcal conjugate vaccine against radiographic pneumonia among children in rural Bangladesh: A case-control study.

BACKGROUND: Pneumococcal conjugate vaccine (PCV) effectiveness against radiographic pneumonia in South Asia is unknown. Bangladesh introduced PCV10 in 2015 using a three dose primary series (3 + 0). We sought to measure PCV10 effectiveness for two or more vaccine doses on radiographic pneumonia among vaccine-eligible children in rural Bangladesh. METHODS: We conducted a matched case-control study over two years from 2015 to 2017 using clinic and community controls in three subdistricts of Sylhet, Bangladesh. Cases were vaccine eligible 3-35 month olds at Upazila Health Complex outpatient clinics with World Health Organization-defined radiographic primary endpoint pneumonia (radiographic pneumonia). Clinic controls were matched to cases within a one week time window by age, sex, and clinic and had an illness unlikely to be Streptococcus pneumoniae; community controls were healthy and similarly matched within a one week time window by age and sex, and distance from the clinic. We estimated adjusted vaccine effectiveness (aVE) using conditional logistic regression. RESULTS: We matched 1262 cases with 2707 clinic and 2461 community controls. Overall, aVE using clinic controls was 21.4% (95% confidence interval, -0.2%, 38.4%) for ≥2 PCV10 doses and among 3-11 month olds was 47.3% (10.5%, 69.0%) for three doses. aVE increased with higher numbers of doses in clinic control sets (p = 0.007). In contrast, aVE using community controls was 7.6% (95% confidence interval, -22.2%, 30.0%) for ≥2 doses. We found vaccine introduction in the study area faster and less variable than expected with 75% coverage on average, which reduced power. Information bias may also have affected community controls. CONCLUSIONS: Clinic control analyses show PCV10 prevented radiographic pneumonia in Bangladesh, especially among younger children receiving three doses. While both analyses were underpowered, community control enrollment - compared to clinic controls - was more difficult in a complex, pluralistic healthcare system. Future studies in comparable settings may consider alternative study designs.

Usability Testing of a Reusable Pulse Oximeter Probe Developed for Health-Care Workers Caring for Children < 5 Years Old in Low-Resource Settings.

Hypoxemia measured by pulse oximetry predicts child pneumonia mortality in low-resource settings (LRS). Existing pediatric oximeter probes are prohibitively expensive and/or difficult to use, limiting LRS implementation. Using a human-centered design, we developed a low-cost, reusable pediatric oximeter probe for LRS health-care workers (HCWs). Here, we report probe usability testing. Fifty-one HCWs from Malawi, Bangladesh, and the United Kingdom participated, and seven experts provided reference measurements. Health-care workers and experts measured the peripheral arterial oxyhemoglobin saturation (SpO2) independently in < 5 year olds. Health-care worker measurements were classed as successful if recorded in 5 minutes (or shorter) and physiologically appropriate for the child, using expert measurements as the reference. All expert measurements were considered successful if obtained in < 5 minutes. We analyzed the proportion of successful SpO2 measurements obtained in < 1, < 2, and < 5 minutes and used multivariable logistic regression to predict < 1 minute successful measurements. We conducted four testing rounds with probe modifications between rounds, and obtained 1,307 SpO2 readings. Overall, 67% (876) of measurements were successful and achieved in < 1 minute, 81% (1,059) < 2 minutes, and 90% (1,181) < 5 minutes. Compared with neonates, increasing age (infant adjusted odds ratio [aOR]; 1.87, 95% confidence interval [CI]: 1.16, 3.02; toddler aOR: 4.33, 95% CI: 2.36, 7.97; child aOR; 3.90, 95% CI: 1.73, 8.81) and being asleep versus being calm (aOR; 3.53, 95% CI: 1.89, 6.58), were associated with < 1 minute successful measurements. In conclusion, we designed a novel, reusable pediatric oximetry probe that was effectively used by LRS HCWs on children. This probe may be suitable for LRS implementation.

Availability of emergency obstetric care (EmOC) among public and private health facilities in rural northwest Bangladesh.

BACKGROUND: Although safe motherhood strategies recommend that women seek timely care from health facilities for obstetric complications, few studies have described facility availability of emergency obstetric care (EmOC). We sought to describe and compare availability and readiness to provide EmOC among public and private health facilities commonly visited for pregnancy-related complications in two districts of northwest Bangladesh. We also described aspects of financial and geographic access to healthcare and key constraints to EmOC provision. METHODS: Using data from a large population-based community trial, we identified and surveyed the 14 health facilities (7 public, 7 private) most frequently visited for obstetric complications and near misses as reported by women. Availability of EmOC was based on provision of medical services, assessed through clinician interviews and record review. Levels of EmOC availability were defined as basic or comprehensive. Readiness for EmOC provision was based on scores in four categories: staffing, equipment, laboratory capacity, and medicines. Readiness scores were calculated using unweighted averages. Costs of C-section procedures and geographic locations of facilities were described. Textual analysis was used to identify key constraints. RESULTS: The seven surveyed private facilities offered comprehensive EmOC compared to four of the seven public facilities. With 100% representing full readiness, mean EmOC readiness was 81% (range: 63%-91%) among surveyed private facilities compared to 67% (range: 48%-91%) in public facilities (p = 0.040). Surveyed public clinics had low scores on staffing and laboratory capacity (69%; 50%). The mean cost of the C-section procedure in private clinics was $77 (standard deviation: $16) and free in public facilities. The public sub-district facilities were the only facilities located in rural areas, with none providing comprehensive EmOC. Shortages in specialized staff were listed as the main barrier to EmOC provision in public facilities. CONCLUSIONS: Although EmOC availability and readiness was higher among the surveyed seven most commonly visited private clinics, public facilities appeared to be more affordable for C-section and more geographically accessible. Strategies to retain anesthesiologists and surgeons, such as non-financial incentives, are needed to improve EmOC provision in the public sector. Centralized blood banks are recommended to streamline safe blood acquisition for obstetric surgeries.

Preferred delivery method and acceptability of Wheat-Soy Blend (WSB++) as a daily complementary food supplement in northwest Bangladesh.

Fortified blended foods (FBFs) are widely used to prevent undernutrition in early childhood in food-insecure settings. We field tested enhanced Wheat Soy Blend (WSB++)-a FBF fortified with micronutrients, milk powder, sugar, and oil-in preparation for a complementary food supplement (CFS) trial in rural northwestern Bangladesh. Formative work was conducted to determine the optimal delivery method (cooked vs. not) for this CFS, to examine mothers' child feeding practices with and acceptance of the WSB++, and to identify potential barriers to adherence. Our results suggest WSB++ is an acceptable CFS in rural Bangladesh and the requirement for mothers to cook WSB++ at home is unlikely to be a barrier to its daily use as a CFS in this population.

Effect of maternal multiple micronutrient vs iron-folic acid supplementation on infant mortality and adverse birth outcomes in rural Bangladesh: the JiVitA-3 randomized trial.

IMPORTANCE: Maternal micronutrient deficiencies may adversely affect fetal and infant health, yet there is insufficient evidence of effects on these outcomes to guide antenatal micronutrient supplementation in South Asia. OBJECTIVE: To assess effects of antenatal multiple micronutrient vs iron-folic acid supplementation on 6-month infant mortality and adverse birth outcomes. DESIGN, SETTING, AND PARTICIPANTS: Cluster randomized, double-masked trial in Bangladesh, with pregnancy surveillance starting December 4, 2007, and recruitment on January 11, 2008. Six-month infant follow-up ended August 30, 2012. Surveillance included 127,282 women; 44,567 became pregnant and were included in the analysis and delivered 28,516 live-born infants. Median gestation at enrollment was 9 weeks (interquartile range, 7-12). INTERVENTIONS: Women were provided supplements containing 15 micronutrients or iron-folic acid alone, taken daily from early pregnancy to 12 weeks postpartum. MAIN OUTCOMES AND MEASURES: The primary outcome was all-cause infant mortality through 6 months (180 days). Prespecified secondary outcomes in this analysis included stillbirth, preterm birth (<37 weeks), and low birth weight (<2500 g). To maintain overall significance of α = .05, a Bonferroni-corrected α = .01 was calculated to evaluate statistical significance of primary and 4 secondary risk outcomes (.05/5). RESULTS: Among the 22,405 pregnancies in the multiple micronutrient group and the 22,162 pregnancies in the iron-folic acid group, there were 14,374 and 14,142 live-born infants, respectively, included in the analysis. At 6 months, multiple micronutrients did not significantly reduce infant mortality; there were 764 deaths (54.0 per 1000 live births) in the iron-folic acid group and 741 deaths (51.6 per 1000 live births) in the multiple micronutrient group (relative risk [RR], 0.95; 95% CI, 0.86-1.06). Multiple micronutrient supplementation resulted in a non-statistically significant reduction in stillbirths (43.1 vs 48.2 per 1000 births; RR, 0.89; 95% CI, 0.81-0.99; P = .02) and significant reductions in preterm births (18.6 vs 21.8 per 100 live births; RR, 0.85; 95% CI, 0.80-0.91; P < .001) and low birth weight (40.2 vs 45.7 per 100 live births; RR, 0.88; 95% CI, 0.85-0.91; P < .001). CONCLUSIONS AND RELEVANCE: In Bangladesh, antenatal multiple micronutrient compared with iron-folic acid supplementation did not reduce all-cause infant mortality to age 6 months but resulted in a non-statistically significant reduction in stillbirths and significant reductions in preterm births and low birth weight. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00860470.