Gut microbiome signature and nasal lavage inflammatory markers in young people with asthma

Background

Asthma is a complex disease and a severe global public health problem resulting from interactions between genetic background and environmental exposures. It has been suggested that gut microbiota may be related to asthma development; however, such relationships needs further investigation.

Objective

This study aimed to characterize the gut microbiota as well as the nasal lavage cytokine profile of asthmatic and nonasthmatic individuals.

Methods

Stool and nasal lavage samples were collected from 29 children and adolescents with type 2 asthma and 28 children without asthma in Brazil. Amplicon sequencing of the stool bacterial V4 region of the 16S rRNA gene was performed using Illumina MiSeq. Microbiota analysis was performed by QIIME 2 and PICRUSt2. Type 2 asthma phenotype was characterized by high sputum eosinophil counts and positive skin prick tests for house dust mite, cockroach, and/or cat or dog dander. The nasal immune marker profile was assessed using a customized multiplex panel.

Results

Stool microbiota differed significantly between asthmatic and nonasthmatic participants (P = .001). Bacteroides was more abundant in participants with asthma (P < .05), while Prevotella was more abundant in nonasthmatic individuals (P < .05). In people with asthma, the relative abundance of Bacteroides correlated with IL-4 concentration in nasal lavage samples. Inference of microbiota functional capacity identified differential fatty acid biosynthesis in asthmatic compared to nonasthmatic subjects.

Conclusion

The stool microbiota differed between asthmatic and nonasthmatic young people in Brazil. Asthma was associated with higher Bacteroides levels, which correlated with nasal IL-4 concentration.

Sustainable Development Goals' health-related indicators for Brazil and Ecuador: an analysis for the period of 1990-2019

OBJECTIVE

This article aims to analyse the evolution of 40 Sustainable Development Goals' (SDGs) health-related indicators in Brazil and Ecuador from 1990 to 2019.

STUDY DESIGN

Epidemiological study of long-term trends in 40 SDGs' health-related indicators for Brazil and Ecuador from 1990 to 2019, using estimates from the Global Burden of Disease Study.

METHODS

Forty SDGs' health-related indicators and an index from 1990 to 2017 for Brazil and Ecuador, and their projections up to 2030 were extracted from the Institute for Health Metrics and Evaluation's Global Burden of Disease website and analysed. The percent annual change (PC) between 1990 and 2019 was calculated for both countries.

RESULTS

Both countries have made progress on child stunting (Brazil: PC = -38%; Ecuador: PC = -43%) and child wasting prevalences (Brazil: PC = -42%; Ecuador: PC = -41%), percent of vaccine coverage (Brazil: PC = +215%; Ecuador: PC = +175%), under-5 (Brazil: PC = -75%; Ecuador: PC = -60%) and neonatal mortality rates (Brazil: PC = -69%; Ecuador: PC = -51%), health worker density per 1000 population (Brazil: PC = +153%; Ecuador: PC = +175%), reduction of neglected diseases prevalences (Brazil: PC = -40%; Ecuador: PC = -58%), tuberculosis (Brazil: PC = -27%; Ecuador: PC = -55%) and malaria incidences (Brazil: PC = -97%; Ecuador: PC = -100%), water, sanitation and hygiene mortality rates (Brazil and Ecuador: PC = -89%). However, both countries did not show sufficient improvement in maternal mortality ratio to meet SDGs targets (Brazil: PC = -37%; Ecuador: PC = -40%). Worsening of indicators were found for violence, such as non-intimate partner violence for both countries (Brazil: PC = +26%; Ecuador: PC = +18%) and suicide mortality rate for Ecuador (PC = +66%), child overweight indicator for Brazil (PC = -67%), disaster mortality rates (Brazil: PC = +100%; Ecuador: PC = +325%) and alcohol consumption (Brazil: PC = +46%; Ecuador: PC = +35%).

CONCLUSIONS

Significant improvements are necessary in both countries requiring the strengthening of health and other policies, particularly concerning the prevention and management of violence and alcohol consumption, and preparedness for dealing with environmental disasters.

Comparing the effect of imputation reference panel composition in four distinct Latin American cohorts

Genome-wide association studies have been useful in identifying genetic risk factors for various phenotypes. These studies rely on imputation and many existing panels are largely composed of individuals of European ancestry, resulting in lower levels of imputation quality in underrepresented populations. We aim to analyze how the composition of imputation reference panels affects imputation quality in four target Latin American cohorts. We compared imputation quality for chromosomes 7 and X when altering the imputation reference panel by: 1) increasing the number of Latin American individuals; 2) excluding either Latin American, African, or European individuals, or 3) increasing the Indigenous American (IA) admixture proportions of included Latin Americans. We found that increasing the number of Latin Americans in the reference panel improved imputation quality in the four populations; however, there were differences between chromosomes 7 and X in some cohorts. Excluding Latin Americans from analysis resulted in worse imputation quality in every cohort, while differential effects were seen when excluding Europeans and Africans between and within cohorts and between chromosomes 7 and X. Finally, increasing IA-like admixture proportions in the reference panel increased imputation quality at different levels in different populations. The difference in results between populations and chromosomes suggests that existing and future reference panels containing Latin American individuals are likely to perform differently in different Latin American populations.

Evaluating the relationship between conditional cash transfer programme on preterm births: a retrospective longitudinal study using the 100 million Brazilian cohort

BACKGROUND

Preterm births increase mortality and morbidity during childhood and later life, which is closely associated with poverty and the quality of prenatal care. Therefore, income redistribution and poverty reduction initiatives may be valuable in preventing this outcome. We assessed whether receipt of the Brazilian conditional cash transfer programme - Bolsa Familia Programme, the largest in the world - reduces the occurrence of preterm births, including their severity categories, and explored how this association differs according to prenatal care and the quality of Bolsa Familia Programme management.

METHODS

A retrospective cohort study was performed involving the first live singleton births to mothersenrolled in the 100 Million Brazilian Cohort from 2004 to 2015, who had at least one child before cohort enrollment. Only the first birth during the cohort period was included, but born from 2012 onward. A deterministic linkage with the Bolsa Familia Programme payroll dataset and a similarity linkage with the Brazilian Live Birth Information System were performed. The exposed group consisted of newborns to mothers who received Bolsa Familia from conception to delivery. Our outcomes were infants born with a gestational age < 37 weeks: (i) all preterm births, (ii) moderate-to-late (32-36), (iii) severe (28-31), and (iv) extreme (< 28) preterm births compared to at-term newborns. We combined propensity score-based methods and weighted logistic regressions to compare newborns to mothers who did and did not receive Bolsa Familia, controlling for socioeconomic conditions. We also estimated these effects separately, according to the adequacy of prenatal care and the index of quality of Bolsa Familia Programme management.

RESULTS

1,031,053 infants were analyzed; 65.9% of the mothers were beneficiaries. Bolsa Familia Programme was not associated with all sets of preterm births, moderate-to-late, and severe preterm births, but was associated with a reduction in extreme preterm births (weighted OR: 0.69; 95%CI: 0.63-0.76). This reduction can also be observed among mothers receiving adequate prenatal care (weighted OR: 0.66; 95%CI: 0.59-0.74) and living in better Bolsa Familia management municipalities (weighted OR: 0.56; 95%CI: 0.43-0.74).

CONCLUSIONS

An income transfer programme for pregnant women of low-socioeconomic status, conditional to attending prenatal care appointments, has been associated with a reduction in extremely preterm births. These programmes could be essential in achieving Sustainable Development Goals.

Income determines the impact of cash transfers on HIV/AIDS: cohort study of 22.7 million Brazilians

Living with extremely low-income is an important risk factor for HIV/AIDS and can be mitigated by conditional cash transfers. Using a cohort of 22.7 million low-income individuals during 9 years, we evaluated the effects of the world's largest conditional cash transfer, the Programa Bolsa Família, on HIV/AIDS-related outcomes. Exposure to Programa Bolsa Família was associated with reduced AIDS incidence by 41% (RR:0.59; 95%CI:0.57-0.61), mortality by 39% (RR:0.61; 95%CI:0.57-0.64), and case fatality rates by 25% (RR:0.75; 95%CI:0.66-0.85) in the cohort, and Programa Bolsa Família effects were considerably stronger among individuals of extremely low-income [reduction of 55% for incidence (RR:0.45, 95% CI:0.42-0.47), 54% mortality (RR:0.46, 95% CI:0.42-0.49), and 37% case-fatality (RR:0.63, 95% CI:0.51 -0.76)], decreasing gradually until having no effect in individuals with higher incomes. Similar effects were observed on HIV notification. Programa Bolsa Família impact was also stronger among women and adolescents. Several sensitivity and triangulation analyses demonstrated the robustness of the results. Conditional cash transfers can significantly reduce AIDS morbidity and mortality in extremely vulnerable populations and should be considered an essential intervention to achieve AIDS-related sustainable development goals by 2030.

Association of interpregnancy interval with adverse pregnancy outcomes according to the outcomes of the preceding pregnancy: a longitudinal study with 4.7 million live births from Brazil

Background

Earlier studies have proposed a link between the Interpregnancy Interval (IPI) and unfavorable birth outcomes. However, it remains unclear if the outcomes of previous births could affect this relationship. We aimed to investigate whether the occurrence of adverse outcomes-small for gestational age (SGA), preterm birth (PTB), and low birth weight (LBW)-at the immediately preceding pregnancy could alter the association between IPI and the same outcomes at the subsequent pregnancy.

Methods

We used a population-based linked cohort from Brazil (2001-2015). IPI was measured as the difference, in months, between the preceding birth and subsequent conception. Outcomes included SGA (<10th birthweight percentile for gestational age and sex), LBW (<2500 g), and PTB (gestational age <37 weeks). We calculated risk ratios (RRs), using the IPI of 18-22 months as the reference IPI category, we also stratified by the number of adverse birth outcomes at the preceding pregnancy.

Findings

Among 4,788,279 births from 3,804,152 mothers, absolute risks for subsequent SGA, PTB, and LBW were higher for women with more adverse outcomes in the preceding delivery. The RR of SGA and LBW for IPIs <6 months were greater for women without previous adverse outcomes (SGA: 1.44 [95% Confidence Interval (CI): 1.41-1.46]; LBW: 1.49 [1.45-1.52]) compared to those with three previous adverse outcomes (SGA: 1.20 [1.10-1.29]; LBW: 1.24 [1.15-1.33]). IPIs ≥120 months were associated with greater increases in risk for LBW and PTB among women without previous birth outcomes (LBW: 1.59; [1.53-1.65]; PTB: 2.45 [2.39-2.52]) compared to women with three adverse outcomes at the index birth (LBW: 0.92 [0.78-1.06]; PTB: 1.66 [1.44-1.88]).

Interpretation

Our study suggests that women with prior adverse outcomes may have higher risks for adverse birth outcomes in subsequent pregnancies. However, risk changes due to differences in IPI length seem to have a lesser impact compared to women without a prior event. Considering maternal obstetric history is essential in birth spacing counseling.

Funding

Wellcome Trust225925/Z/22/Z.

Postnatal growth in small vulnerable newborns: a longitudinal study of 2 million Brazilians using routine register-based linked data

BACKGROUND

Preterm, low-birth weight (LBW) and small-for-gestational age (SGA) newborns have a higher frequency of adverse health outcomes, including linear and ponderal growth impairment.

OBJECTIVE

To describe the growth trajectories and to estimate catch-up growth during the first 5 y of life of small newborns according to 3 vulnerability phenotypes (preterm, LBW, SGA).

METHODS

Longitudinal study using linked data from the 100 Million Brazilian Cohort baseline, the Brazilian National Live Birth System (SINASC), and the Food and Nutrition Surveillance System (SISVAN) from 2011 to 2017. We estimated the length/height-for-age (L/HAZ) and weight-for-age z-score (WAZ) trajectories from children of 6-59 mo using the linear mixed model for each vulnerable newborn phenotype. Growth velocity for both L/HAZ and WAZ was calculated considering the change (Δ) in the mean z-score between 2 time points. Catch-up growth was defined as a change in z-score > 0.67 at any time during follow-up.

RESULTS

We analyzed 2,021,998 live born children and 8,726,599 observations. The prevalence of at least one of the vulnerable phenotypes was 16.7% and 0.6% were simultaneously preterm, LBW, and SGA. For those born at term, all phenotypes had a period of growth recovery from 12 mo. For preterm infants, the onset of L/HAZ growth recovery started later at 24 mo and the growth trajectories appear to be lower than those born at term, a condition aggravated among children with the 3 phenotypes. Preterm and female infants seem to experience slower growth recovery than those born at term and males. The catch-up growth occurs at 24-59 mo for males preterm: preterm + AGA + NBW (Δ = 0.80), preterm + AGA + LBW (Δ = 0.88), and preterm + SGA + LBW (Δ = 1.08); and among females: term + SGA + NBW (Δ = 0.69), term + AGA + LBW (Δ = 0.72), term + SGA + LBW (Δ = 0.77), preterm + AGA + LBW (Δ = 0.68), and preterm + SGA + LBW (Δ = 0.83).

CONCLUSIONS

Children born preterm seem to reach L/HAZ and WAZ growth trajectories lower than those attained by children born at term, a condition aggravated among the most vulnerable.

Combining Digital and Molecular Approaches Using Health and Alternate Data Sources in a Next-Generation Surveillance System for Anticipating Outbreaks of Pandemic Potential

Globally, millions of lives are impacted every year by infectious diseases outbreaks. Comprehensive and innovative surveillance strategies aiming at early alert and timely containment of emerging and reemerging pathogens are a pressing priority. Shortcomings and delays in current pathogen surveillance practices further disturbed informing responses, interventions, and mitigation of recent pandemics, including H1N1 influenza and SARS-CoV-2. We present the design principles of the architecture for an early-alert surveillance system that leverages the vast available data landscape, including syndromic data from primary health care, drug sales, and rumors from the lay media and social media to identify areas with an increased number of cases of respiratory disease. In these potentially affected areas, an intensive and fast sample collection and advanced high-throughput genome sequencing analyses would inform on circulating known or novel pathogens by metagenomics-enabled pathogen characterization. Concurrently, the integration of bioclimatic and socioeconomic data, as well as transportation and mobility network data, into a data analytics platform, coupled with advanced mathematical modeling using artificial intelligence or machine learning, will enable more accurate estimation of outbreak spread risk. Such an approach aims to readily identify and characterize regions in the early stages of an outbreak development, as well as model risk and patterns of spread, informing targeted mitigation and control measures. A fully operational system must integrate diverse and robust data streams to translate data into actionable intelligence and actions, ultimately paving the way toward constructing next-generation surveillance systems.

Income Segregation, Conditional Cash Transfers, and Breast Cancer Mortality Among Women in Brazil

Importance

Women living in income-segregated areas are less likely to receive adequate breast cancer care and access community resources, which may heighten breast cancer mortality risk.

Objective

To investigate the association between income segregation and breast cancer mortality and whether this association is attenuated by receipt of the Bolsa Família program (BFP), the world's largest conditional cash-transfer program.

Design, Setting, and Participants

This cohort study was conducted using data from the 100 Million Brazilian Cohort, which were linked with nationwide mortality registries (2004-2015). Data were analyzed from December 2021 to June 2023. Study participants were women aged 18 to 100 years.

Exposure

Women's income segregation (high, medium, or low) at the municipality level was obtained using income data from the 2010 Brazilian census and assessed using dissimilarity index values in tertiles (low [0.01-0.25], medium [0.26-0.32], and high [0.33-0.73]).

Main Outcomes and Measures

The main outcome was breast cancer mortality. Mortality rate ratios (MRRs) for the association of segregation with breast cancer deaths were estimated using Poisson regression adjusted for age, race, education, municipality area size, population density, area of residence (rural or urban), and year of enrollment. Multiplicative interactions of segregation and BFP receipt (yes or no) in the association with mortality (2004-2015) were assessed.

Results

Data on 21 680 930 women (mean [SD] age, 36.1 [15.3] years) were analyzed. Breast cancer mortality was greater among women living in municipalities with high (adjusted MRR [aMRR], 1.18; 95% CI, 1.13-1.24) and medium (aMRR, 1.08; 95% CI, 1.03-1.12) compared with low segregation. Women who did not receive BFP had higher breast cancer mortality than BFP recipients (aMRR, 1.17; 95% CI, 1.12-1.22). By BFP strata, women who did not receive BFP and lived in municipalities with high income segregation had a 24% greater risk of death from breast cancer compared with those living in municipalities with low income segregation (aMRR, 1.24: 95% CI, 1.14-1.34); women who received BFP and were living in areas with high income segregation had a 13% higher risk of death from breast cancer compared with those living in municipalities with low income segregation (aMRR, 1.13; 95% CI, 1.07-1.19; P for interaction = .008). Stratified by the amount of time receiving the benefit, segregation (high vs low) was associated with an increase in mortality risk for women receiving BFP for less time but not for those receiving it for more time (<4 years: aMRR, 1.16; 95% CI, 1.07-1.27; 4-11 years: aMRR, 1.09; 95% CI, 1.00-1.17; P for interaction <.001).

Conclusions and Relevance

These findings suggest that place-based inequities in breast cancer mortality associated with income segregation may be mitigated with BFP receipt, possibly via improved income and access to preventive cancer care services among women, which may be associated with early detection and treatment and ultimately reduced mortality.

The intersection of race/ethnicity and socioeconomic status: inequalities in breast and cervical cancer mortality in 20,665,005 adult women from the 100 Million Brazilian Cohort

OBJECTIVES

There is limited evidence regarding the impact of race/racism and its intersection with socioeconomic status (SES) on breast and cervical cancer, the two most common female cancers globally. We investigated racial inequalities in breast and cervical cancer mortality and whether SES (education and household conditions) interacted with race/ethnicity.

DESIGN

The 100 Million Brazilian Cohort data were linked to the Brazilian Mortality Database, 2004-2015 (n = 20,665,005 adult women). We analysed the association between self-reported race/ethnicity (White/'Parda'(Brown)/Black/Asian/Indigenous) and cancer mortality using Poisson regression, adjusting for age, calendar year, education, household conditions and area of residence. Additive and multiplicative interactions were assessed.

RESULTS

Cervical cancer mortality rates were higher among Indigenous (adjusted Mortality rate ratio = 1.80, 95%CI 1.39-2.33), Asian (1.63, 1.20-2.22), 'Parda'(Brown) (1.27, 1.21-1.33) and Black (1.18, 1.09-1.28) women vs White women. Breast cancer mortality rates were higher among Black (1.10, 1.04-1.17) vs White women. Racial inequalities in cervical cancer mortality were larger among women of poor household conditions, and low education (P for multiplicative interaction <0.001, and 0.02, respectively). Compared to White women living in completely adequate (3-4) household conditions, the risk of cervical cancer mortality in Black women with 3-4, 1-2, and none adequate conditions was 1.10 (1.01-1.21), 1.48 (1.28-1.71), and 2.03 (1.56-2.63), respectively (Relative excess risk due to interaction-RERI = 0.78, 0.18-1.38). Among 'Parda'(Brown) women the risk was 1.18 (1.11-1.25), 1.68 (1.56-1.81), and 1.84 (1.63-2.08), respectively (RERI = 0.52, 0.16-0.87). Compared to high-educated White women, the risk in high-, middle- and low-educated Black women was 1.14 (0.83-1.55), 1.93 (1.57-2.38) and 2.75 (2.33-3.25), respectively (RERI = 0.36, -0.05-0.77). Among 'Parda'(Brown) women the risk was 1.09 (0.91-1.31), 1.99 (1.70-2.33) and 3.03 (2.61-3.52), respectively (RERI = 0.68, 0.48-0.88). No interactions were found for breast cancer.

CONCLUSION

Low SES magnified racial inequalities in cervical cancer mortality. The intersection between race/ethnicity, SES and gender needs to be addressed to reduce racial health inequalities.

Perinatal health outcomes of international migrant women in Brazil: A nationwide data linkage study of the CIDACS birth cohort (2011-2018)

BACKGROUND

We investigated perinatal outcomes among live births from international migrant and local-born mothers in a cohort of low-income individuals in Brazil.

METHODS

We linked nationwide birth registries to mortality records and socioeconomic data from the CIDACS Birth Cohort and studied singleton live births of women aged 10-49 years from 1st January 2011 to 31st December 2018. We used logistic regressions to investigate differences in antenatal care, adverse pregnancy outcomes, and neonatal (i.e., ≤28 days) mortality among international migrants compared to non-migrants in Brazil; and explored the interaction between migration, race/ethnicity and living in international border municipalities.

RESULTS

We studied 10,279,011 live births, of which 9469 (0.1 %) were born to international migrants. Migrant women were more likely than their Brazilian-born counterparts to have a previous foetal loss (ORadj: 1.16, 1.11-1.22), a delayed start of antenatal care (i.e., beyond 1st trimester) (1.22, 95%CI:1.16-1.28), a newborn who is large for gestational age (1.29, 1.22-1.36), or a newborn with congenital anomalies (1.37, 1.14-1.65). Conversely, migrant women were less likely to deliver prematurely (0.89, 0.82-0.95) or have a low birth weight infant (0.74, 0.68-0.81). There were no differences in neonatal mortality rates between migrants and non-migrants. Our analyses also showed that, when disparities in perinatal outcomes were present, disparities were mostly concentrated among indigenous mothers in international borders and among live births of Black mothers in non-borders.

CONCLUSION

Although live births of international migrants generally have lower rates of adverse birth outcomes, our results suggest that indigenous and Black migrant mothers may face disproportionate barriers to accessing antenatal care.

Participation in Conditional Cash Transfer Program During Pregnancy and Birth Weight-Related Outcomes

Importance

There is limited evidence of the association of conditional cash transfers, an important strategy to reduce poverty, with prevention of adverse birth-related outcomes.

Objective

To investigate the association between receiving benefits from the Bolsa Família Program (BFP) and birth weight indicators.

Design, Setting, and Participants

This cohort study used a linked data resource, the Centro de Integracao de Dados e Conhecimentos Para Saude (CIDACS) birth cohort. All live-born singleton infants born to mothers registered in the cohort between January 2012 and December 2015 were included. Each analysis was conducted for the overall population and separately by level of education, self-reported maternal race, and number of prenatal appointments. Data were analyzed from January 3 to April 24, 2023.

Exposure

Live births of mothers who had received BFP until delivery (for a minimum of 9 months) were classified as exposed and compared with live births from mothers who did not receive the benefit prior to delivery.

Main Outcomes and Measures

Low birth weight (LBW), birth weight in grams, and small for gestational age (SGA) were evaluated. Analytical methods used included propensity score estimation, kernel matching, and weighted logistic and linear regressions. Race categories included Parda, which translates from Portuguese as "brown" and is used to denote individuals whose racial background is predominantly Black and those with multiracial or multiethnic ancestry, including European, African, and Indigenous origins.

Results

A total of 4 277 523 live births (2 085 737 females [48.8%]; 15 207 among Asian [0.4%], 334 225 among Black [7.8%], 29 115 among Indigenous [0.7%], 2 588 363 among Parda [60.5%], and 1 310 613 among White [30.6%] mothers) were assessed. BFP was associated with an increase of 17.76 g (95% CI, 16.52-19.01 g) in birth weight. Beneficiaries had an 11% lower chance of LBW (odds ratio [OR], 0.89; 95% CI, 0.88-0.90). BFP was associated with a greater decrease in odds of LBW among subgroups of mothers who attended fewer than 7 appointments (OR, 0.85; 95% CI, 0.84-0.87), were Indigenous (OR, 0.73; 95% CI, 0.61-0.88), and had 3 or less years of education (OR, 0.76; 95% CI, 0.72-0.81). There was no association between BFP and SGA, except among less educated mothers, who had a reduced risk of SGA (OR, 0.83; 95% CI, 0.79-0.88).

Conclusions and Relevance

This study found that BFP was associated with increased birth weight and reduced odds of LBW, with a greater decrease in odds of LBW among higher-risk groups. These findings suggest the importance of maintaining financial support for mothers at increased risk of birth weight-related outcomes.

Maternal and congenital syphilis attributable to ethnoracial inequalities: a national record-linkage longitudinal study of 15 million births in Brazil

BACKGROUND

This study estimated ethnoracial inequalities in maternal and congenital syphilis in Brazil, understanding race as a relational category product of a sociopolitical construct that functions as an essential tool of racism and its manifestations.

METHODS

We linked routinely collected data from Jan 1, 2012 to Dec 31, 2017 to conduct a population-based study in Brazil. We estimated the attributable fraction of race (skin colour) for the entire population and specific subgroups compared with White women using adjusted logistic regression. We also obtained the attributable fraction of the intersection between two social markers (race and education) and compared it with White women with more than 12 years of education as the baseline.

FINDINGS

Of 15 810 488 birth records, 144 564 women had maternal syphilis and 79 580 had congenital syphilis. If all women had the same baseline risk as White women, 35% (95% CI 34·89-36·10) of all maternal syphilis and 41% (40·49-42·09) of all congenital syphilis would have been prevented. Compared with other ethnoracial categories, these percentages were higher among Parda/Brown women (46% [45·74-47·20] of maternal syphilis and 52% [51·09-52·93] of congenital syphilis would have been prevented) and Black women (61% [60·25-61·75] of maternal syphilis and 67% [65·87-67·60] of congenital syphilis would have been prevented). If all ethnoracial groups had the same risk as White women with more than 12 years of education, 87% of all maternal syphilis and 89% of all congenital syphilis would have been prevented.

INTERPRETATION

Only through effective control of maternal syphilis among populations at higher risk (eg, Black and Parda/Brown women with lower educational levels) can WHO's global health initiative to eliminate mother-to-child transmission of syphilis be made feasible. Recognising that racism and other intersecting forms of oppression affect the lives of minoritised groups and advocating for actions through the lens of intersectionality is imperative for attaining and guaranteeing health equity. Achieving health equality needs to be addressed to achieve syphilis control. Given the scale and complexity of the problem (which is unlikely to be unique to Brazil), structural issues and social markers of oppression, such as race and education, must be considered to prevent maternal and congenital syphilis and improve maternal and child outcomes globally.

FUNDING

Wellcome Trust, CNPq-Brazil.

TRANSLATION

For the Portuguese translation of the abstract see Supplementary Materials section.

The effect of primary health care on AIDS incidence and mortality: a cohort study of 3.4 million Brazilians

Background

Primary Health Care (PHC) is essential for the health and wellbeing of people living with HIV/AIDS. This study evaluated the effects of one of the largest community-based PHC programs in the world, the Brazilian Family Health Strategy (FHS), on AIDS incidence and mortality.

Methods

A retrospective cohort study carried out in Brazil, from January 1 2007 to December 31 2015. We conducted a quasi-experimental effect evaluation using a cohort of 3,435,068 ≥13 years low-income individuals who were members of the 100 Million Brazilians Cohort, linked to AIDS diagnoses and deaths registries. We evaluated the effect of FHS on AIDS incidence and mortality and comparing outcomes between residents of municipalities with no FHS coverage with those in municipalities with full FHS coverage. We used multivariable Poisson regressions adjusted for all relevant municipal and individual-level demographic, socioeconomic, and contextual variables, and weighted with inverse probability of treatment weighting (IPTW). We also estimated FHS effect by sex and age, and performed a wide range of sensitivity and triangulation analyses.

Findings

FHS coverage was associated with lower AIDS incidence (rate ratio [RR]:0.76, 95%CI:0.68-0.84) and mortality (RR:0.68,95%CI:0.56-0.82). FHS effect was similar between men and women, but was larger in people aged ≥35 years old both for incidence (RR 0.62, 95%CI:0.53-0.72) and mortality (RR 0.56, 95%CI:0.43-0.72).

Conclusions

AIDS should be an avoidable outcome for most people living with HIV today, and our study shows that FHS coverage could significantly reduce AIDS incidence and mortality among low-income populations in Brazil. Universal access to comprehensive healthcare through community-based PHC programs should be promoted to achieve the Sustainable Development Goals of ending AIDS by 2030.

Suicide among Indigenous peoples in Brazil from 2000 to 2020: a descriptive study

Background

Previous studies in Australia, Canada, and Brazil, found that suicide among ethnic minority groups is higher than in the general population. Indigenous peoples in Brazil have been reported to have a high suicide rate, with reports of suicide clusters occurring in several communities. The objective of this study was to report trends in countrywide suicide rates among Indigenous peoples in Brazil between 2000 and 2020, and to compare these with the non-Indigenous population.

Methods

This ecological study used Indigenous suicide data collected from all regions of Brazil during a 21-year period, between 2000 and 2020. We used suicide estimates from the Mortality Information System (SIM), available at the Brazilian Health Ministry website (DATASUS). Suicide mortality rates by state and region were calculated using the estimated Indigenous population from the 2010 census, and estimated population proportions for the other years. We performed a trend analysis and compared trends in suicide between the Indigenous and non-Indigenous population during the period studied.

Findings

Suicide rates among Indigenous Brazilians have reached more than two and a half times the levels for the overall Brazilian population in 2020 (17.57 suicide deaths versus 6.35 suicide deaths per 100,000 inhabitants, respectively). The Central-West region of Brazil had the highest suicide rates among Indigenous Brazilians over the study period, reaching 58.8 deaths/100,000 inhabitants in 2008. The younger age group (10-24 years old) had the highest suicide rates for all the years studied. Time-series analyses showed a trend of statistically significant increases in suicide rates in Brazil for both the Indigenous and non-Indigenous population during the study period. The North region, and specifically Amazonas state, has shown a decisive increase in suicide rates among the Indigenous populations. The suicide rate for Indigenous people in Brazil, excluding cases in Amazonas and Mato Grosso do Sul states, were similar to those for the entire Brazilian population, showing that the Indigenous peoples who are the most vulnerable to suicide reside in these locations.

Interpretation

While there were statistically significant increases in suicide rates for all Brazilians over the study period, they remained alarmingly high among Indigenous people, compared to their non-Indigenous counterparts. The high suicide rates among Indigenous people, and younger individuals in particular (aged between 10 and 24), reinforces the need for specific prevention strategies for these populations. Further studies should be concentrated on determining risk factors in distinct ethnic groups, specifically within regions experiencing an elevated risk, such as the states of Amazonas and Mato Grosso do Sul.

Funding

Research reported in this publication was supported by the National Institute of Mental Health of the National Institutes of Health under award number R01MH128911-01. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Maternal and child nutrition programme of investigation within the 100 Million Brazilian Cohort: study protocol

INTRODUCTION

There is a limited understanding of the early nutrition and pregnancy determinants of short-term and long-term maternal and child health in ethnically diverse and socioeconomically vulnerable populations within low-income and middle-income countries. This investigation programme aims to: (1) describe maternal weight trajectories throughout the life course; (2) describe child weight, height and body mass index (BMI) trajectories; (3) create and validate models to predict childhood obesity at 5 years of age; (4) estimate the effects of prepregnancy BMI, gestational weight gain (GWG) and maternal weight trajectories on adverse maternal and neonatal outcomes and child growth trajectories; (5) estimate the effects of prepregnancy BMI, GWG, maternal weight and interpregnancy BMI changes on maternal and child outcomes in the subsequent pregnancy; and (6) estimate the effects of maternal food consumption and infant feeding practices on child nutritional status and growth trajectories.

METHODS AND ANALYSIS

Linked data from four different Brazilian databases will be used: the 100 Million Brazilian Cohort, the Live Births Information System, the Mortality Information System and the Food and Nutrition Surveillance System. To analyse trajectories, latent-growth, superimposition by translation and rotation and broken stick models will be used. To create prediction models for childhood obesity, machine learning techniques will be applied. For the association between the selected exposure and outcomes variables, generalised linear models will be considered. Directed acyclic graphs will be constructed to identify potential confounders for each analysis investigating potential causal relationships.

ETHICS AND DISSEMINATION

This protocol was approved by the Research Ethics Committees of the authors' institutions. The linkage will be carried out in a secure environment. After the linkage, the data will be de-identified, and pre-authorised researchers will access the data set via a virtual private network connection. Results will be reported in open-access journals and disseminated to policymakers and the broader public.

Cesarean sections and early-term births according to Robson classification: a population-based study with more than 17 million births in Brazil

BACKGROUND

Cesarean section (CS) rates are increasing worldwide and are associated with negative maternal and child health outcomes when performed without medical indication. However, there is still limited knowledge about the association between high CS rates and early-term births. This study explored the association between CSs and early-term births according to the Robson classification.

METHODS

A population-based, cross-sectional study was performed with routine registration data of live births in Brazil between 2012 and 2019. We used the Robson classification system to compare groups with expected high and low CS rates. We used propensity scores to compare CSs to vaginal deliveries (1:1) and estimated associations with early-term births using logistic regression.

RESULTS

A total of 17,081,685 live births were included. Births via CS had higher odds of early-term birth (OR 1.32; 95% CI 1.32-1.32) compared to vaginal deliveries. Births by CS to women in Group 2 (OR 1.50; 95% CI 1.49-1.51) and 4 (OR 1.57; 95% CI 1.56-1.58) showed the highest odds of early-term birth, compared to vaginal deliveries. Increased odds of an early-term birth were also observed among births by CS to women in Group 3 (OR 1.30, 95% CI 1.29-1.31), compared to vaginal deliveries. In addition, live births by CS to women with a previous CS (Group 5 - OR 1.36, 95% CI 1.35-1.37), a single breech pregnancy (Group 6 - OR 1.16; 95% CI 1.11-1.21, and Group 7 - OR 1.19; 95% CI 1.16-1.23), and multiple pregnancies (Group 8 - OR 1.46; 95% CI 1.40-1.52) had high odds of an early-term birth, compared to live births by vaginal delivery.

CONCLUSIONS

CSs were associated with increased odds of early-term births. The highest odds of early-term birth were observed among those births by CS in Robson Groups 2 and 4.

The effects of social determinants of health on acquired immune deficiency syndrome in a low-income population of Brazil: a retrospective cohort study of 28.3 million individuals

Background

Social determinants of health (SDH) include factors such as income, education, and race, that could significantly affect the human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS). Studies on the effects of SDH on HIV/AIDS are limited, and do not yet provide a systematic understanding of how the various SDH act on important indicators of HIV/AIDS progression. We aimed to evaluate the effects of SDH on AIDS morbidity and mortality.

Methods

A retrospective cohort of 28.3 million individuals was evaluated over a 9-year period (from 2007 to 2015). Multivariable Poisson regression, with a hierarchical approach, was used to estimate the effects of SDH-at the individual and familial level-on AIDS incidence, mortality, and case-fatality rates.

Findings

A total of 28,318,532 individuals, representing the low-income Brazilian population, were assessed, who had a mean age of 36.18 (SD: 16.96) years, 52.69% (14,920,049) were female, 57.52% (15,360,569) were pardos, 34.13% (9,113,222) were white/Asian, 7.77% (2,075,977) were black, and 0.58% (154,146) were indigenous. Specific socioeconomic, household, and geographic factors were significantly associated with AIDS-related outcomes. Less wealth was strongly associated with a higher AIDS incidence (rate ratios-RR: 1.55; 95% confidence interval-CI: 1.43-1.68) and mortality (RR: 1.99; 95% CI: 1.70-2.34). Lower educational attainment was also greatly associated with higher AIDS incidence (RR: 1.46; 95% CI: 1.26-1.68), mortality (RR: 2.76; 95% CI: 1.99-3.82) and case-fatality rates (RR: 2.30; 95% CI: 1.31-4.01). Being black was associated with a higher AIDS incidence (RR: 1.53; 95% CI: 1.45-1.61), mortality (RR: 1.69; 95% CI: 1.57-1.83) and case-fatality rates (RR: 1.16; 95% CI: 1.03-1.32). Overall, also considering the other SDH, individuals experiencing greater levels of socioeconomic deprivation were, by far, more likely to acquire AIDS, and to die from it.

Interpretation

In the population studied, SDH related to poverty and social vulnerability are strongly associated with a higher burden of HIV/AIDS, most notably less wealth, illiteracy, and being black. In the absence of relevant social protection policies, the current worldwide increase in poverty and inequalities-due to the consequences of the COVID-19 pandemic, and the effects of war in the Ukraine-could reverse progress made in the fight against HIV/AIDS in low- and middle-income countries (LMIC).

Funding

National Institute of Allergy and Infectious Diseases (NAIDS), National Institutes of Health (NIH), US Grant Number: 1R01AI152938.

Municipality-level measles, mumps, and rubella (MMR) vaccine coverage and deprivation in Brazil: A nationwide ecological study, 2006 to 2020

To better understand the declining rates of routine childhood vaccination in Brazil, we investigated the association between measles, mumps, and rubella (MMR) first dose vaccine coverage and deprivation at the municipality level. Using routinely collected data from 5565 Brazilian municipalities from 2006 to 2020, we investigated the association between municipality-level MMR vaccine first dose coverage (i.e., as a continuous variable and as a percentage of municipalities attaining the 95% target coverage) in relation to quintiles of municipality-level deprivation, measured by the Brazilian Deprivation Index (Índice Brasileiro de Privação, IBP), and geographic regions. From 2006 to 2020, the mean municipality-level MMR vaccine coverage declined across all deprivation quintiles and regions of Brazil, by an average of 1.2% per year. The most deprived quintile of municipalities had higher coverage on average, but also the steepest declines in coverage (i.e., an annual decline of 1.64% versus 0.61% in the least deprived quintile) in the period of 2006-2020, and the largest drop in coverage at the beginning of the COVID-19 pandemic (2019-2020). Across all deprivation quintiles and regions (except for the Southeast region), less than 50% of municipalities in Brazil met the 95% MMR coverage target in 2020.The decrease in MMR first dose vaccine coverage in Brazil is widespread, but steeper declines have been observed in the most deprived municipalities. To promote vaccine equity and prevent future outbreaks, further research is urgently needed to understand the causal mechanisms underlying the observed associations between municipality-level MMR vaccine coverage and deprivation.

Vaccine coverage and effectiveness against laboratory-confirmed symptomatic and severe Covid-19 in indigenous people in Brazil: a cohort study

BACKGROUND

Indigenous people have historically suffered devastating impacts from epidemics and continue to have lower access to healthcare and be especially vulnerable to respiratory infections. We estimated the coverage and effectiveness of Covid-19 vaccines against laboratory-confirmed Covid-19 cases among indigenous people in Brazil.

METHODS

We linked nationwide Covid-19 vaccination data with flu-like surveillance records and studied a cohort of vaccinated indigenous people aged ≥ 5 years between 18th January 2021 and 1st March 2022. We considered individuals unexposed from the date they received the first dose of vaccine until the 13th day of vaccination, partially vaccinated from the 14th day after the first dose until the 13th day after receiving the second dose, and fully vaccinated onwards. We estimated the Covid-19 vaccination coverage and used Poisson regression to calculate the relative risks (RR) and vaccine effectiveness (VE) of CoronaVac, ChAdOx1, and BNT162b2 against Covid-19 laboratory-confirmed cases incidence, mortality, hospitalisation, and hospital-progression to Intensive Care Unit (ICU) or death. VE was estimated as (1-RR)*100, comparing unexposed to partially or fully vaccinated.

RESULTS

By 1st March 2022, 48.7% (35.0-62.3) of eligible indigenous people vs. 74.8% (57.9-91.8) overall Brazilians had been fully vaccinated for Covid-19. Among fully vaccinated indigenous people, we found a lower risk of symptomatic cases (RR: 0.47, 95%CI: 0.40-0.56) and mortality (RR: 0.47, 95%CI: 0.14-1.56) after the 14th day of the second dose. VE for the three Covid-19 vaccines combined was 53% (95%CI:44-60%) for symptomatic cases, 53% (95%CI:-56-86%) for mortality and 41% (95%CI:-35-75%) for hospitalisation. In our sample, we found that vaccination did not reduce Covid-19 related hospitalisation. However, among hospitalised patients, we found a lower risk of progression to ICU (RR: 0.14, 95%CI: 0.02-0.81; VE: 87%, 95%CI:27-98%) and Covid-19 death (RR: 0.04, 95%CI:0.01-0.10; VE: 96%, 95%CI: 90-99%) after the 14th day of the second dose.

CONCLUSIONS

Lower coverage but similar Covid-19 VE among indigenous people than overall Brazilians suggest the need to expand access, timely vaccination, and urgently offer booster doses to achieve a great level of protection among this group.

Subsidised housing and diabetes mortality: a retrospective cohort study of 10 million low-income adults in Brazil

INTRODUCTION

Housing-related factors can be predictors of health, including of diabetes outcomes. We analysed the association between subsidised housing residency and diabetes mortality among a large cohort of low-income adults in Brazil.

RESEARCH DESIGN AND METHODS

A cohort of 9 961 271 low-income adults, observed from January 2010 to December 2015, was created from Brazilian administrative records of social programmes and death certificates. We analysed the association between subsidised housing residency and time to diabetes mortality using a Cox model with inverse probability of treatment weighting and regression adjustment. We assessed inequalities in this association by groups of municipality Human Development Index. Diabetes mortality included diabetes both as the underlying or a contributory cause of death.

RESULTS

At baseline, the mean age of the cohort was 40.3 years (SD 15.6 years), with a majority of women (58.4%). During 29 238 920 person-years of follow-up, there were 18 775 deaths with diabetes as the underlying or a contributory cause. 340 683 participants (3.4% of the cohort) received subsidised housing. Subsidised housing residents had a higher hazard of diabetes mortality compared with non-residents (HR 1.17; 95% CI 1.05 to 1.31). The magnitude of this association was more pronounced among participants living in municipalities with lower Human Development Index (HR 1.30; 95% CI 1.04 to 1.62).

CONCLUSIONS

Subsidised housing residents had a greater risk of diabetes mortality, particularly those living in low socioeconomic status municipalities. This finding suggests the need to intensify diabetes prevention and control actions and prompt treatment of the diabetes complications among subsidised housing residents, particularly among those living in low socioeconomic status municipalities.

Neonatal mortality risk for vulnerable newborn types in 15 countries using 125.5 million nationwide birth outcome records, 2000-2020

OBJECTIVE

To compare neonatal mortality associated with six novel vulnerable newborn types in 125.5 million live births across 15 countries, 2000-2020.

DESIGN

Population-based, multi-country study.

SETTING

National data systems in 15 middle- and high-income countries.

METHODS

We used individual-level data sets identified for the Vulnerable Newborn Measurement Collaboration. We examined the contribution to neonatal mortality of six newborn types combining gestational age (preterm [PT] versus term [T]) and size-for-gestational age (small [SGA], <10th centile, appropriate [AGA], 10th-90th centile or large [LGA], >90th centile) according to INTERGROWTH-21st newborn standards. Newborn babies with PT or SGA were defined as small and T + LGA was considered as large. We calculated risk ratios (RRs) and population attributable risks (PAR%) for the six newborn types.

MAIN OUTCOME MEASURES

Mortality of six newborn types.

RESULTS

Of 125.5 million live births analysed, risk ratios were highest among PT + SGA (median 67.2, interquartile range [IQR] 45.6-73.9), PT + AGA (median 34.3, IQR 23.9-37.5) and PT + LGA (median 28.3, IQR 18.4-32.3). At the population level, PT + AGA was the greatest contributor to newborn mortality (median PAR% 53.7, IQR 44.5-54.9). Mortality risk was highest among newborns born before 28 weeks (median RR 279.5, IQR 234.2-388.5) compared with babies born between 37 and 42 completed weeks or with a birthweight less than 1000 g (median RR 282.8, IQR 194.7-342.8) compared with those between 2500 g and 4000 g as a reference group.

CONCLUSION

Preterm newborn types were the most vulnerable, and associated with the highest mortality, particularly with co-existence of preterm and SGA. As PT + AGA is more prevalent, it is responsible for the greatest burden of neonatal deaths at population level.

Mortality in children under 5 years of age with congenital syphilis in Brazil: A nationwide cohort study

BACKGROUND

Congenital syphilis (CS) is a major and avoidable cause of neonatal death worldwide. In this study, we aimed to estimate excess all-cause mortality in children under 5 years with CS compared to those without CS.

METHODS AND FINDINGS

In this population-based cohort study, we used linked, routinely collected data from Brazil from January 2011 to December 2017. Cox survival models were adjusted for maternal region of residence, maternal age, education, material status, self-declared race and newborn sex, and year of birth and stratified according to maternal treatment status, non-treponemal titers and presence of signs and symptoms at birth. Over 7 years, a total of 20 057 013 live-born children followed up (through linkage) to 5 years of age, 93 525 were registered with CS, and 2 476 died. The all-cause mortality rate in the CS group was 7·84/1 000 person-years compared with 2·92/1 000 person-years in children without CS, crude hazard ratio (HR) = 2·41 (95% CI 2·31 to 2·50). In the fully adjusted model, the highest under-five mortality risk was observed among children with CS from untreated mothers HR = 2·82 (95% CI 2·63 to 3·02), infants with non-treponemal titer higher than 1:64 HR = 8·87 (95% CI 7·70 to 10·22), and children with signs and symptoms at birth HR = 7·10 (95% CI 6·60 to 7·63). Among children registered with CS, CS was recorded as the underlying cause of death in 33% (495/1 496) of neonatal, 11% (85/770) of postneonatal, and 2·9% (6/210) of children 1 year of age. The main limitations of this study were the use of a secondary database without additional clinical information and the potential misclassification of exposure status.

CONCLUSIONS

This study showed an increased mortality risk among children with CS that goes beyond the first year of life. It also reinforces the importance of maternal treatment that infant non-treponemal titers and the presence of signs and symptoms of CS at birth are strongly associated with subsequent mortality.

TRIAL REGISTRATION

Observational study.

Temporal trends in prevalence and infant mortality of birth defects in Brazil, from 2001 to 2018

Congenital anomalies (CA) are a relevant problem for global public health, affecting about 3% to 6% of newborns worldwide. In Brazil, these are the second main cause of infant mortality. Thus, extensive studies are needed to demonstrate the impact of these anomalies on births and deaths. The present study describes the temporal trends of prevalence and infant mortality due to CA among live births in Brazil and regions, from 2001 to 2018, using the related data between the Live Birth Information System (SINASC, acronym in Portuguese) and the Mortality Information System (SIM, acronym in Portuguese). The prevalence and infant mortality due to CA has increased in Brazil and in most regions, especially in the Northeast and North. CAs in the musculoskeletal system were the most frequent at birth (29.8/10,000 live births), followed by those in the circulatory system (12.7/10,000 live births), which represented the primary cause of death in this group. The applied linkage technique made it possible to correct the national prevalence of CA by 17.9% during the analyzed period, after retrieving the anomalies reported in SIM, thereby proving to be a good tool to improve the quality of information on anomalies in Brazil.

Mortality among over 6 million internal and international migrants in Brazil: a study using the 100 Million Brazilian Cohort

Background

To understand if migrants living in poverty in low and middle-income countries (LMICs) have mortality advantages over the non-migrant population, we investigated mortality risk patterns among internal and international migrants in Brazil over their life course.

Methods

We linked socio-economic and mortality data from 1st January 2011 to 31st December 2018 in the 100 Million Brazilian Cohort and calculated all-cause and cause-specific age-standardised mortality rates according to individuals' migration status for men and women. Using Cox regression models, we estimated the age- and sex-adjusted mortality hazard ratios (HR) for internal migrants (i.e., Brazilian-born individuals living in a different Brazilian state than their birth) compared to Brazilian-born non-migrants; and for international migrants (i.e., people born in another country) compared to Brazilian-born individuals.

Findings

The study followed up 45,051,476 individuals, of whom 6,057,814 were internal migrants, and 277,230 were international migrants. Internal migrants had similar all-cause mortality compared to Brazilian non-migrants (aHR = 0.99, 95% CI = 0.98-0.99), marginally higher mortality for ischaemic heart diseases (aHR = 1.04, 95% CI = 1.03-1.05) and higher for stroke (aHR = 1.11, 95% CI = 1.09-1.13). Compared to Brazilian-born individuals, international migrants had 18% lower all-cause mortality (aHR = 0.82, 95% CI = 0.80-0.84), with up to 50% lower mortality from interpersonal violence among men (aHR = 0.50, 95% CI = 0.40-0.64), but higher mortality from avoidable causes related to maternal health (aHR = 2.17, 95% CI = 1.17-4.05).

Interpretation

Although internal migrants had similar all-cause mortality, international migrants had lower all-cause mortality compared to non-migrants. Further investigations using intersectional approaches are warranted to understand the marked variations by migration status, age, and sex for specific causes of death, such as elevated maternal mortality and male lower interpersonal violence-related mortality among international migrants.

Funding

The Wellcome Trust.

National data linkage assessment of live births and deaths in Mexico: Estimating under-five mortality rate ratios for vulnerable newborns and trends from 2008 to 2019

BACKGROUND

Linked datasets that enable longitudinal assessments are scarce in low and middle-income countries.

OBJECTIVES

We aimed to assess the linkage of administrative databases of live births and under-five child deaths to explore mortality and trends for preterm, small (SGA) and large for gestational age (LGA) in Mexico.

METHODS

We linked individual-level datasets collected by National statistics from 2008 to 2019. Linkage was performed based on agreement on birthday, sex, residential address. We used the Centre for Data and Knowledge Integration for Health software to identify the best candidate pairs based on similarity. Accuracy was assessed by calculating the area under the receiver operating characteristic curve. We evaluated completeness by comparing the number of linked records with reported deaths. We described the percentage of linked records by baseline characteristics to identify potential bias. Using the linked dataset, we calculated mortality rate ratios (RR) in neonatal, infants, and children under-five according to gestational age, birthweight, and size.

RESULTS

For the period 2008-2019, a total of 24,955,172 live births and 321,165 under-five deaths were available for linkage. We excluded 1,539,046 records (6.2%) with missing or implausible values. We succesfully linked 231,765 deaths (72.2%: range 57.1% in 2009 and 84.3% in 2011). The rate of neonatal mortality was higher for preterm compared with term (RR 3.83, 95% confidence interval, CI 3.78, 3.88) and for SGA compared with appropriate for gestational age (AGA) (RR 1.22 95% CI, 1.19, 1.24). Births at <28 weeks had the highest mortality (RR 35.92, 95%CI, 34.97, 36.88). LGA had no additional risk vs AGA among children under five (RR 0.92, 95%CI, 0.90, 0.93).

CONCLUSIONS

We demonstrated the utility of linked data to understand neonatal vulnerability and child mortality. We created a linked dataset that would be a valuable resource for future population-based research.

Understanding and controlling asthma in Latin America: A review of recent research informed by the SCAALA programme

Asthma is an important health concern in Latin America (LA) where it is associated with variable prevalence and disease burden between countries. High prevalence and morbidity have been observed in some regions, particularly marginalized urban populations. Research over the past 10 years from LA has shown that childhood disease is primarily non-atopic. The attenuation of atopy may be explained by enhanced immune regulation induced by intense exposures to environmental factors such as childhood infections and poor environmental conditions of the urban poor. Non-atopic symptoms are associated with environmental and lifestyle factors including poor living conditions, respiratory infections, psychosocial stress, obesity, and a diet of highly processed foods. Ancestry (particularly African) and genetic factors increase asthma risk, and some of these factors may be specific to LA settings. Asthma in LA tends to be poorly controlled and depends on access to health care and medications. There is a need to improve management and access to medication through primary health care. Future research should consider the heterogeneity of asthma to identify relevant endotypes and underlying causes. The outcome of such research will need to focus on implementable strategies relevant to populations living in resource-poor settings where the disease burden is greatest.

Causes of death in children with congenital Zika syndrome in Brazil, 2015 to 2018: A nationwide record linkage study

BACKGROUND

Children with congenital Zika syndrome (CZS) have severe damage to the peripheral and central nervous system (CNS), greatly increasing the risk of death. However, there is no information on the sequence of the underlying, intermediate, immediate, and contributing causes of deaths among these children. The aims of this study are describe the sequence of events leading to death of children with CZS up to 36 months of age and their probability of dying from a given cause, 2015 to 2018.

METHODS AND FINDINGS

In a population-based study, we linked administrative data on live births, deaths, and cases of children with CZS from the SINASC (Live Birth Information System), the SIM (Mortality Information System), and the RESP (Public Health Event Records), respectively. Confirmed and probable cases of CZS were those that met the criteria established by the Brazilian Ministry of Health. The information on causes of death was collected from death certificates (DCs) using the World Health Organization (WHO) DC template. We estimated proportional mortality (PM%) among children with CZS and among children with non-Zika CNS congenital anomalies (CA) by 36 months of age and proportional mortality ratio by cause (PMRc). A total of 403 children with confirmed and probable CZS who died up to 36 months of age were included in the study; 81.9% were younger than 12 months of age. Multiple congenital malformations not classified elsewhere, and septicemia unspecified, with 18 (PM = 4.5%) and 17 (PM = 4.2%) deaths, respectively, were the most attested underlying causes of death. Unspecified septicemia (29 deaths and PM = 11.2%) and newborn respiratory failure (40 deaths and PM = 12.1%) were, respectively, the predominant intermediate and immediate causes of death. Fetuses and newborns affected by the mother's infectious and parasitic diseases, unspecified cerebral palsy, and unspecified severe protein-caloric malnutrition were the underlying causes with the greatest probability of death in children with CZS (PMRc from 10.0 to 17.0) when compared to the group born with non-Zika CNS anomalies. Among the intermediate and immediate causes of death, pneumonitis due to food or vomiting and unspecified seizures (PMRc = 9.5, each) and unspecified bronchopneumonia (PMRc = 5.0) were notable. As contributing causes, fetus and newborn affected by the mother's infectious and parasitic diseases (PMRc = 7.3), unspecified cerebral palsy, and newborn seizures (PMRc = 4.5, each) were more likely to lead to death in children with CZS than in the comparison group. The main limitations of this study were the use of a secondary database without additional clinical information and potential misclassification of cases and controls.

CONCLUSION

The sequence of causes and circumstances involved in the deaths of the children with CZS highlights the greater vulnerability of these children to infectious and respiratory conditions compared to children with abnormalities of the CNS not related to Zika.

Effectiveness of mRNA boosters after homologous primary series with BNT162b2 or ChAdOx1 against symptomatic infection and severe COVID-19 in Brazil and Scotland: A test-negative design case-control study

BACKGROUND

Brazil and Scotland have used mRNA boosters in their respective populations since September 2021, with Omicron's emergence accelerating their booster program. Despite this, both countries have reported substantial recent increases in Coronavirus Disease 2019 (COVID-19) cases. The duration of the protection conferred by the booster dose against symptomatic Omicron cases and severe outcomes is unclear.

METHODS AND FINDINGS

Using a test-negative design, we analyzed national databases to estimate the vaccine effectiveness (VE) of a primary series (with ChAdOx1 or BNT162b2) plus an mRNA vaccine booster (with BNT162b2 or mRNA-1273) against symptomatic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection and severe COVID-19 outcomes (hospitalization or death) during the period of Omicron dominance in Brazil and Scotland compared to unvaccinated individuals. Additional analyses included stratification by age group (18 to 49, 50 to 64, ≥65). All individuals aged 18 years or older who reported acute respiratory illness symptoms and tested for SARS-CoV-2 infection between January 1, 2022, and April 23, 2022, in Brazil and Scotland were eligible for the study. At 14 to 29 days after the mRNA booster, the VE against symptomatic SARS-CoV-2 infection of ChAdOx1 plus BNT162b2 booster was 51.6%, (95% confidence interval (CI): [51.0, 52.2], p < 0.001) in Brazil and 67.1% (95% CI [65.5, 68.5], p < 0.001) in Scotland. At ≥4 months, protection against symptomatic infection waned to 4.2% (95% CI [0.7, 7.6], p = 0.02) in Brazil and 37.4% (95% CI [33.8, 40.9], p < 0.001) in Scotland. VE against severe outcomes in Brazil was 93.5% (95% CI [93.0, 94.0], p < 0.001) at 14 to 29 days post-booster, decreasing to 82.3% (95% CI [79.7, 84.7], p < 0.001) and 98.3% (95% CI [87.3, 99.8], p < 0.001) to 77.8% (95% CI [51.4, 89.9], p < 0.001) in Scotland for the same periods. Similar results were obtained with the primary series of BNT162b2 plus homologous booster. Potential limitations of this study were that we assumed that all cases included in the analysis were due to the Omicron variant based on the period of dominance and the limited follow-up time since the booster dose.

CONCLUSIONS

We observed that mRNA boosters after a primary vaccination course with either mRNA or viral-vector vaccines provided modest, short-lived protection against symptomatic infection with Omicron but substantial and more sustained protection against severe COVID-19 outcomes for at least 3 months.

A multinational Delphi consensus to end the COVID-19 public health threat

Despite notable scientific and medical advances, broader political, socioeconomic and behavioural factors continue to undercut the response to the COVID-19 pandemic1,2. Here we convened, as part of this Delphi study, a diverse, multidisciplinary panel of 386 academic, health, non-governmental organization, government and other experts in COVID-19 response from 112 countries and territories to recommend specific actions to end this persistent global threat to public health. The panel developed a set of 41 consensus statements and 57 recommendations to governments, health systems, industry and other key stakeholders across six domains: communication; health systems; vaccination; prevention; treatment and care; and inequities. In the wake of nearly three years of fragmented global and national responses, it is instructive to note that three of the highest-ranked recommendations call for the adoption of whole-of-society and whole-of-government approaches1, while maintaining proven prevention measures using a vaccines-plus approach2 that employs a range of public health and financial support measures to complement vaccination. Other recommendations with at least 99% combined agreement advise governments and other stakeholders to improve communication, rebuild public trust and engage communities3 in the management of pandemic responses. The findings of the study, which have been further endorsed by 184 organizations globally, include points of unanimous agreement, as well as six recommendations with >5% disagreement, that provide health and social policy actions to address inadequacies in the pandemic response and help to bring this public health threat to an end.

Vaccine effectiveness of two-dose BNT162b2 against symptomatic and severe COVID-19 among adolescents in Brazil and Scotland over time: a test-negative case-control study

BACKGROUND

Little is known about vaccine effectiveness over time among adolescents, especially against the SARS-CoV-2 omicron (B.1.1.529) variant. This study assessed the associations between time since two-dose vaccination with BNT162b2 and the occurrence of symptomatic SARS-CoV-2 infection and severe COVID-19 among adolescents in Brazil and Scotland.

METHODS

We did test-negative, case-control studies in adolescents aged 12-17 years with COVID-19-related symptoms in Brazil and Scotland. We linked records of SARS-CoV-2 RT-PCR and antigen tests to national vaccination and clinical records. We excluded tests from individuals who did not have symptoms, were vaccinated before the start of the national vaccination programme, received vaccines other than BNT162b2 or a SARS-CoV-2 booster dose of any kind, or had an interval between their first and second dose of fewer than 21 days. Additionally, we excluded negative SARS-CoV-2 tests recorded within 14 days of a previous negative test, negative tests recorded within 7 days after a positive test, any test done within 90 days after a positive test, and tests with missing sex and location information. Cases (SARS-CoV-2 test-positive adolescents) and controls (test-negative adolescents) were drawn from a sample of individuals in whom tests were collected within 10 days of symptom onset. We estimated the adjusted odds ratio and vaccine effectiveness against symptomatic COVID-19 for both countries and against severe COVID-19 (hospitalisation or death) for Brazil across fortnightly periods.

FINDINGS

We analysed 503 776 tests from 2 948 538 adolescents in Brazil between Sept 2, 2021, and April 19, 2022, and 127 168 tests from 404 673 adolescents in Scotland between Aug 6, 2021, and April 19, 2022. Vaccine effectiveness peaked at 14-27 days after the second dose in both countries during both waves, and was significantly lower against symptomatic infection during the omicron-dominant period in Brazil (64·7% [95% CI 63·0-66·3]) and in Scotland (82·6% [80·6-84·5]), than it was in the delta-dominant period (80·7% [95% CI 77·8-83·3] in Brazil and 92·8% [85·7-96·4] in Scotland). Vaccine efficacy started to decline from 27 days after the second dose for both countries, reducing to 5·9% (95% CI 2·2-9·4) in Brazil and 50·6% (42·7-57·4) in Scotland at 98 days or more during the omicron-dominant period. In Brazil, protection against severe disease remained above 80% from 28 days after the second dose and was 82·7% (95% CI 68·8-90·4) at 98 days or more after receiving the second dose.

INTERPRETATION

We found waning vaccine protection of BNT162b2 against symptomatic COVID-19 infection among adolescents in Brazil and Scotland from 27 days after the second dose. However, protection against severe COVID-19 outcomes remained high at 98 days or more after the second dose in the omicron-dominant period. Booster doses for adolescents need to be considered.

FUNDING

UK Research and Innovation (Medical Research Council), Scottish Government, Health Data Research UK BREATHE Hub, Fiocruz, Fazer o Bem Faz Bem programme, Brazilian National Research Council, and Wellcome Trust.

TRANSLATION

For the Portuguese translation of the abstract see Supplementary Materials section.

Mortality among internal and international migrants in the 100 Million Brazilian Cohort

Background

There is limited evidence on the health of migrant populations in low and middle-income countries (LMICs). Here, we investigated the patterns of mortality risk in migrants and non-migrants in women and men over the life course.

Methods

We linked socioeconomic and mortality data from 1st Jan 2011 to 31st Dec 2018 in the 100 Million Brazilian Cohort. We calculated all-cause and cause-specific age-standardised mortality rates according to individuals’ migration status. Using Cox regression models, we estimated the age- and sex-adjusted mortality hazard ratios (HR) for internal migrants (i.e., people born in Brazil but living in a different Brazilian state to their state of birth) compared to Brazilian-born non-migrants; and for international migrants (i.e., people born in another country) compared to Brazilian-born individuals.

Results

We followed 45,051,476 individuals, of whom 6,057,814 were internal migrants and 277,230 were international migrants. Internal migrants had a similar overall risk of all-cause mortality compared to Brazilian non-migrants (aHR=0.99, 95%CI=0.98-0.99), with lower mortality from some causes but higher mortality for some non-communicable diseases (NCDs). Compared to Brazilian-born individuals, international migrants had a lower risk of all-cause mortality (aHR=0.82, 95%CI=0.80-0.84), with up to 50% lower risk of death attributed to interpersonal violence among international migrant men (aHR=0.50, 95%CI=0.40-0.64), but a markedly higher risk of death by avoidable causes related to maternal health among young migrant women (aHR=2.17, 95%CI=1.17-4.05).

Conclusions

Overall, internal migration was not associated with excess all-cause mortality, while international migration into Brazil was associated with lower all-cause mortality. Mortality patterns among migrant populations in Brazil show marked variation for specific causes of death, and risks varied by age and sex.

Key messages

• Non-communicable diseases and maternal mortality are disproportionally higher among internal and international migrants, respectively.

• Further investigation of the underlying factors associated with higher maternal mortality among international migrant women is key to informing the targeting of social and health interventions.

The impact of social drivers, conditional cash transfers and their mechanisms on the mental health of the young; an integrated retrospective and forecasting approach using the 100 million Brazilian Cohort: A study protocol

Background

Physical, emotional, and social changes, including exposure to poverty, abuse, or violence, increases youth vulnerability to mental illness. These factors interfere with development, limit opportunities, and hamper achievement of a fulfilling life as adults. Addressing these issues can lead to improved outcomes at the population level and better cost-effectiveness for health services. Cash transfer programs have been a promising way to address social drivers for poor mental health. However, it is still unclear which pathways and mechanisms explain the association between socioeconomic support and lower mental illness among youth. Therefore, we will evaluate the effect of social drivers on youth mental health-related hospitalizations and suicide, test mechanisms and pathways of a countrywide socioeconomic intervention, and examine the timing of the intervention during the life course.

Methods

We will combine individual-level data from youth national hospitalization, mental health disorders and attempted suicide, suicide registries and notifications of violence, with large-scale databases, including “The 100 Million Brazilian Cohort”, over an 18-year period (2001–2018). Several approaches will be used for the retrospective quasi-experimental impact evaluations, such as Regression Discontinuity Designs, Propensity Score Matching and difference-in-differences, combined with multivariable regressions for cohort analyses. We will run multivariate regressions based on hierarchical analysis approach to evaluate the association between important social drivers (mental health care, demographic and economic aspects) on mental health-related hospitalizations and suicide among youth. Furthermore, we will perform microsimulations to generate projections regarding how mental health-related hospitalizations and suicide trends will be in the future based on the current state, and how BFP implementation scenarios will affect these trends.

Discussion

The results of this project will be of vital importance to guide policies and programs to improve mental health and reduce mental health-related hospitalizations and suicide in youth. It will provide information to improve the effectiveness of these programs worldwide. If cash transfers can decrease mental health problems among youth and reduce suicide.

Main and moderated effects of multimorbidity and depressive symptoms on cognition

OBJECTIVE

Multimorbidity, or the occurrence of two or more chronic conditions, is a global challenge, with implications for mortality, morbidity, disability, and life quality. Psychiatric disorders are common among the chronic diseases that affect patients with multimorbidity. It is still not well understood whether psychiatric symptoms, especially depressive symptoms, moderate the effect of multimorbidity on cognition.

METHODS

We used a large (n=2,681) dataset to assess whether depressive symptomatology moderates the effect of multimorbidity on cognition using structural equation modelling.

RESULTS

It was found that the more depressive symptoms and chronic conditions, the worse the cognitive performance, and the higher the educational level, the better the cognitive performance. We found a significant but weak (0.009; p = 0.04) moderating effect.

CONCLUSION

We have provided the first estimate of the moderating effect of depression on the relation between multimorbidity and cognition, which was small. Although this moderation has been implied by many previous studies, it was never previously estimated.

Impact of Brazil's Bolsa Família Programme on cardiovascular and all-cause mortality: a natural experiment study using the 100 Million Brazilian Cohort

BACKGROUND

Cardiovascular disease (CVD) has a disproportionate effect on mortality among the poorest people. We assessed the impact on CVD and all-cause mortality of the world's largest conditional cash transfer, Brazil's Bolsa Família Programme (BFP).

METHODS

We linked administrative data from the 100 Million Brazilian Cohort with BFP receipt and national mortality data. We followed individuals who applied for BFP between 1 January 2011 and 31 December 2015, until 31 December 2015. We used marginal structural models to estimate the effect of BFP on all-age and premature (30-69 years) CVD and all-cause mortality. We conducted stratified analyses by levels of material deprivation and access to healthcare. We checked the robustness of our findings by restricting the analysis to municipalities with better mortality data and by using alternative statistical methods.

RESULTS

We studied 17 981 582 individuals, of whom 4 855 324 were aged 30-69 years. Three-quarters (76.2%) received BFP, with a mean follow-up post-award of 2.6 years. We detected 106 807 deaths by all causes, of which 60 893 were premature; and 23 389 CVD deaths, of which 15 292 were premature. BFP was associated with reductions in premature all-cause mortality [hazard ratio (HR) = 0.96, 95% CI = 0.94-0.98], premature CVD (HR = 0.96, 95% CI = 0.92-1.00) and all-age CVD (HR = 0.96, 95% CI = 0.93-1.00) but not all-age all-cause mortality (HR = 1.00, 95% CI = 0.98-1.02). In stratified and robustness analyses, BFP was consistently associated with mortality reductions for individuals living in the two most deprived quintiles.

CONCLUSIONS

BFP appears to have a small to null effect on premature CVD and all-cause mortality in the short term; the long-term impact remains unknown.

Patterns of multimorbidity and some psychiatric disorders: A systematic review of the literature

Objective

The presence of two or more chronic diseases results in worse clinical outcomes than expected by a simple combination of diseases. This synergistic effect is expected to be higher when combined with some conditions, depending on the number and severity of diseases. Multimorbidity is a relatively new term, with the first fundamental definitions appearing in 2015. Studies usually define it as the presence of at least two chronic medical illnesses. However, little is known regarding the relationship between mental disorders and other non-psychiatric chronic diseases. This review aims at investigating the association between some mental disorders and non-psychiatric diseases, and their pattern of association.

Methods

We performed a systematic approach to selecting papers that studied relationships between chronic conditions that included one mental disorder from 2015 to 2021. These were processed using Covidence, including quality assessment.

Results

This resulted in the inclusion of 26 papers in this study. It was found that there are strong associations between depression, psychosis, and multimorbidity, but recent studies that evaluated patterns of association of diseases (usually using clustering methods) had heterogeneous results. Quality assessment of the papers generally revealed low quality among the included studies.

Conclusions

There is evidence of an association between depressive disorders, anxiety disorders, and psychosis with multimorbidity. Studies that tried to examine the patterns of association between diseases did not find stable results.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021216101, identifier: CRD42021216101.

Socioeconomic risk markers of congenital Zika syndrome: a nationwide, registry-based study in Brazil

While it is well known that socioeconomic markers are associated with a higher risk of arbovirus infections, research on the relationship between socioeconomic factors and congenital Zika syndrome (CZS) remains limited. This study investigates the relationship between socioeconomic risk markers and live births with CZS in Brazil. We conducted a population-based study using data from all registered live births in Brazil (Live Births Information System) linked with the Public Health Event Record from 1 January 2015 to 31 December 2018. We used logistic regression models to estimate the OR and 95% CIs of CZS based on a three-level framework. In an analysis of 11 366 686 live births, of which 3353 had CZS, we observed that live births of self-identified black or mixed race/brown mothers (1.72 (95% CI 1.47 to 2.01) and 1.37 (95% CI 1.24 to 1.51)) were associated with a higher odds of CZS. Live births from single women compared with married women and those from women with less than 12 years of education compared with those with more than 12 years of education also had higher odds of CZS. In addition, live births following fewer prenatal care appointments had increased odds of CZS in the nationwide data. However, in the analyses conducted in the Northeast region (where the microcephaly epidemic started before the link with Zika virus was established and before preventive measures were known or disseminated), no statistical association was found between the number of prenatal care appointments and the odds of CZS. This study shows that live births of the most socially vulnerable women in Brazil had the greatest odds of CZS. This disproportionate distribution of risk places an even greater burden on already socioeconomically disadvantaged groups, and the lifelong disabilities caused by this syndrome may reinforce existing social and health inequalities.

Asthma inflammatory phenotypes on four continents: most asthma is non-eosinophilic

BACKGROUND

Most studies assessing pathophysiological heterogeneity in asthma have been conducted in high-income countries (HICs), with little known about the prevalence and characteristics of different asthma inflammatory phenotypes in low-and middle-income countries (LMICs). This study assessed sputum inflammatory phenotypes in five centres, in Brazil, Ecuador, Uganda, New Zealand (NZ) and the United Kingdom (UK).

METHODS

We conducted a cross-sectional study of 998 asthmatics and 356 non-asthmatics in 2016-20. All centres studied children and adolescents (age range 8-20 years), except the UK centre which involved 26-27 year-olds. Information was collected using questionnaires, clinical characterization, blood and induced sputum.

RESULTS

Of 623 asthmatics with sputum results, 39% (243) were classified as eosinophilic or mixed granulocytic, i.e. eosinophilic asthma (EA). Adjusted for age and sex, with NZ as baseline, the UK showed similar odds of EA (odds ratio 1.04, 95% confidence interval 0.37-2.94) with lower odds in the LMICs: Brazil (0.73, 0.42-1.27), Ecuador (0.40, 0.24-0.66) and Uganda (0.62, 0.37-1.04). Despite the low prevalence of neutrophilic asthma in most centres, sputum neutrophilia was increased in asthmatics and non-asthmatics in Uganda.

CONCLUSIONS

This is the first time that sputum induction has been used to compare asthma inflammatory phenotypes in HICs and LMICs. Most cases were non-eosinophilic, including in settings where corticosteroid use was low. A lower prevalence of EA was observed in the LMICs than in the HICs. This has major implications for asthma prevention and management, and suggests that novel prevention strategies and therapies specifically targeting non-eosinophilic asthma are required globally.

Vaccine effectiveness of CoronaVac against COVID-19 among children in Brazil during the Omicron period

Although severe COVID-19 in children is rare, they may develop multisystem inflammatory syndrome, long-COVID and downstream effects of COVID-19, including social isolation and disruption of education. Data on the effectiveness of the CoronaVac vaccine is scarce during the Omicron period. In Brazil, children between 6 to 11 years are eligible to receive the CoronaVac vaccine. We conducted a test-negative design to estimate vaccine effectiveness using 197,958 tests from January 21, 2022, to April 15, 2022, during the Omicron dominant period in Brazil among children aged 6 to 11 years. The estimated vaccine effectiveness for symptomatic infection was 39.8% (95% CI 33.7–45.4) at ≥14 days post-second dose. For hospital admission vaccine effectiveness was 59.2% (95% CI 11.3–84.5) at ≥14 days. Two doses of CoronaVac in children during the Omicron period showed low levels of protection against symptomatic infection, and modest levels against severe illness.

There is limited evidence of the effectiveness of the CoronaVac vaccine for children against the Omicron SARS-CoV-2 variant. Here, the authors use data from Brazil for children aged 6–11 years and estimate effectiveness of 40% against infection and 59% against severe disease at least two weeks after the second dose.

Tucuxi-BLAST: Enabling fast and accurate record linkage of large-scale health-related administrative databases through a DNA-encoded approach

Background

Public health research frequently requires the integration of information from different data sources. However, errors in the records and the high computational costs involved make linking large administrative databases using record linkage (RL) methodologies a major challenge.

Methods

We present Tucuxi-BLAST, a versatile tool for probabilistic RL that utilizes a DNA-encoded approach to encrypt, analyze and link massive administrative databases. Tucuxi-BLAST encodes the identification records into DNA. BLASTn algorithm is then used to align the sequences between databases. We tested and benchmarked on a simulated database containing records for 300 million individuals and also on four large administrative databases containing real data on Brazilian patients.

Results

Our method was able to overcome misspellings and typographical errors in administrative databases. In processing the RL of the largest simulated dataset (200k records), the state-of-the-art method took 5 days and 7 h to perform the RL, while Tucuxi-BLAST only took 23 h. When compared with five existing RL tools applied to a gold-standard dataset from real health-related databases, Tucuxi-BLAST had the highest accuracy and speed. By repurposing genomic tools, Tucuxi-BLAST can improve data-driven medical research and provide a fast and accurate way to link individual information across several administrative databases.

Population-based surveillance for congenital zika virus syndrome: a latent class analysis of recorded cases from 2015-2018

Objective

This study aims to describe clinical findings and determine the medium-term survival of congenital zika syndrome (CZS) suspected cases.

Methods

A retrospective cohort study using routine register-based linked data. It included all suspected cases of CZS born in Brazil from January 1, 2015, to December 31, 2018, and followed up from birth until death, 36 months, or December 31, 2018, whichever came first. Latent class analysis was used to cluster unconfirmed cases into classes with similar combinations of anthropometry at birth, imaging findings, maternally reported rash, region, and year of birth. Kaplan–Meier curves were plotted, and Cox proportional hazards models were fitted to determine mortality up to 36 months.

Results

We followed 11,850 suspected cases of CZS, of which 28.3% were confirmed, 9.3% inconclusive and 62.4% unconfirmed. Confirmed cases had almost two times higher mortality when compared with unconfirmed cases. Among unconfirmed cases, we identified three distinct clusters with different mortality trajectories. The highest mortality risk was observed in those with abnormal imaging findings compatible with congenital infections (HR = 12.6; IC95%8.8–18.0) and other abnormalities (HR = 11.6; IC95%8.6–15.6) compared with those with normal imaging findings. The risk was high in those with severe microcephaly (HR = 8.2; IC95%6.4–10.6) and macrocephaly (HR = 6.6; IC95%4.5–9.7) compared with normal head size.

Conclusion

Abnormal imaging and head circumference appear to be the main drivers of the increased mortality among suspected cases of CZS. We suggest identifying children who are more likely to die and have a greater need to optimise interventions and resource allocation regardless of the final diagnoses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04860-3.

Effectiveness of CoronaVac, ChAdOx1 nCoV-19, BNT162b2, and Ad26.COV2.S among individuals with previous SARS-CoV-2 infection in Brazil: a test-negative, case-control study

BACKGROUND

COVID-19 vaccines have proven highly effective among individuals without a previous SARS-CoV-2 infection, but their effectiveness in preventing symptomatic infection and severe outcomes among individuals with previous infection is less clear. We aimed to estimate the effectiveness of four COVID-19 vaccines against symptomatic infection, hospitalisation, and death for individuals with laboratory-confirmed previous SARS-CoV-2 infection.

METHODS

Using national COVID-19 notification, hospitalisation, and vaccination datasets from Brazil, we did a test-negative, case-control study to assess the effectiveness of four vaccines (CoronaVac [Sinovac], ChAdOx1 nCoV-19 [AstraZeneca], Ad26.COV2.S [Janssen], and BNT162b2 [Pfizer-BioNtech]) for individuals with laboratory-confirmed previous SARS-CoV-2 infection. We matched cases with RT-PCR positive, symptomatic COVID-19 with up to ten controls with negative RT-PCR tests who presented with symptomatic illnesses, restricting both groups to tests done at least 90 days after an initial infection. We used multivariable conditional logistic regression to compare the odds of test positivity and the odds of hospitalisation or death due to COVID-19, according to vaccination status and time since first or second dose of vaccines.

FINDINGS

Between Feb 24, 2020, and Nov 11, 2021, we identified 213 457 individuals who had a subsequent, symptomatic illness with RT-PCR testing done at least 90 days after their initial SARS-CoV-2 infection and after the vaccination programme started. Among these, 30 910 (14·5%) had a positive RT-PCR test consistent with reinfection, and we matched 22 566 of these cases with 145 055 negative RT-PCR tests from 68 426 individuals as controls. Among individuals with previous SARS-CoV-2 infection, vaccine effectiveness against symptomatic infection 14 or more days from vaccine series completion was 39·4% (95% CI 36·1-42·6) for CoronaVac, 56·0% (51·4-60·2) for ChAdOx1 nCoV-19, 44·0% (31·5-54·2) for Ad26.COV2.S, and 64·8% (54·9-72·4) for BNT162b2. For the two-dose vaccine series (CoronaVac, ChAdOx1 nCoV-19, and BNT162b2), effectiveness against symptomatic infection was significantly greater after the second dose than after the first dose. Effectiveness against hospitalisation or death 14 or more days from vaccine series completion was 81·3% (75·3-85·8) for CoronaVac, 89·9% (83·5-93·8) for ChAdOx1 nCoV-19, 57·7% (-2·6 to 82·5) for Ad26.COV2.S, and 89·7% (54·3-97·7) for BNT162b2.

INTERPRETATION

All four vaccines conferred additional protection against symptomatic infections and severe outcomes among individuals with previous SARS-CoV-2 infection. The provision of a full vaccine series to individuals after recovery from COVID-19 might reduce morbidity and mortality.

FUNDING

Brazilian National Research Council, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Oswaldo Cruz Foundation, JBS, Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation, and Generalitat de Catalunya.

Differences in risk factors for incident and recurrent preterm birth: a population-based linkage of 3.5 million births from the CIDACS birth cohort

BACKGROUND

Preterm birth (PTB) is a syndrome resulting from a complex list of underlying causes and factors, and whether these risk factors differ in the context of prior PTB history is less understood. The aim of this study was to explore whether PTB risk factors in a second pregnancy were different in women with versus without previous PTB.

METHODS

We conducted a population-based cohort study using data from the birth cohort of the Center for Data and Knowledge Integration for Health (CIDACS) for the period 2001 to 2015. We used longitudinal transition models with multivariate logistic regression to investigate whether risk factors varied between incident and recurrent PTB.

RESULTS

A total of 3,528,050 live births from 1,764,025 multiparous women were analyzed. We identified different risk factors (P_difference <0.05) between incident and recurrent PTB. The following were associated with an increased chance for PTB incidence, but not recurrent: household overcrowding (OR 1.09), maternal race/ethnicity [(Black/mixed-OR 1.04) and (indigenous-OR 1.34)], young maternal age (14 to 19 years-OR 1.16), and cesarean delivery (OR 1.09). The following were associated with both incident and recurrent PTB, respectively: single marital status (OR 0.85 vs 0.90), reduced number of prenatal visits [(no visit-OR 2.56 vs OR 2.16) and (1 to 3 visits-OR 2.44 vs OR 2.24)], short interbirth interval [(12 to 23 months-OR 1.04 vs OR 1.22) and (<12 months, OR 1.89, 95 vs OR 2.58)], and advanced maternal age (35-49 years-OR 1.42 vs OR 1.45). For most risk factors, the point estimates were higher for incident PTB than recurrent PTB.

CONCLUSIONS

The risk factors for PTB in the second pregnancy differed according to women's first pregnancy PTB status. The findings give the basis for the development of specific prevention strategies for PTB in a subsequent pregnancy.

Social inequalities and their impact on children's health: a current and global perspective

OBJECTIVE

To describe the consequences of social inequalities on children's health as a global and persistent problem, demonstrating its historical and structural roots in different societies.

DATA SOURCES

Relevant articles in the PubMed/MEDLINE database, in addition to those found in a manual search and in the bibliographic references of selected studies and consultation to the websites of international organizations to obtain relevant data and documents.

DATA SYNTHESIS

To understand how inequities affect health, it is necessary to know the unequal distribution of their social determinants among population groups. In the case of children, the parental pathway of determinants is central. The non-equitable way in which many families or social groups live, determined by social and economic inequalities, produces unequal health outcomes, particularly for children. This is observed between and within countries. Children from the most vulnerable population groups consistently have worse health conditions. Interventions aimed at children's health must go beyond care and act in an integrated manner on poverty and on social and economic inequalities, aiming to end systematic and unfair differences.

CONCLUSIONS

Despite the considerable advances observed in children's health in recent decades at a global level, the inequalities measured by different indicators show that they persist. This scenario deserves attention from researchers and decision-makers, especially in the context of the global health crisis caused by the COVID-19 pandemic, which has further intensified the situation of vulnerability and social inequalities in health around the world.

Mortality from Congenital Zika Syndrome - Nationwide Cohort Study in Brazil

BACKGROUND

Prenatal exposure to Zika virus has potential teratogenic effects, with a wide spectrum of clinical presentation referred to as congenital Zika syndrome. Data on survival among children with congenital Zika syndrome are limited.

METHODS

In this population-based cohort study, we used linked, routinely collected data in Brazil, from January 2015 through December 2018, to estimate mortality among live-born children with congenital Zika syndrome as compared with those without the syndrome. Kaplan-Meier curves and survival models were assessed with adjustment for confounding and with stratification according to gestational age, birth weight, and status of being small for gestational age.

RESULTS

A total of 11,481,215 live-born children were followed to 36 months of age. The mortality rate was 52.6 deaths (95% confidence interval [CI], 47.6 to 58.0) per 1000 person-years among live-born children with congenital Zika syndrome, as compared with 5.6 deaths (95% CI, 5.6 to 5.7) per 1000 person-years among those without the syndrome. The mortality rate ratio among live-born children with congenital Zika syndrome, as compared with those without the syndrome, was 11.3 (95% CI, 10.2 to 12.4). Among infants born before 32 weeks of gestation or with a birth weight of less than 1500 g, the risks of death were similar regardless of congenital Zika syndrome status. Among infants born at term, those with congenital Zika syndrome were 14.3 times (95% CI, 12.4 to 16.4) as likely to die as those without the syndrome (mortality rate, 38.4 vs. 2.7 deaths per 1000 person-years). Among infants with a birth weight of 2500 g or greater, those with congenital Zika syndrome were 12.9 times (95% CI, 10.9 to 15.3) as likely to die as those without the syndrome (mortality rate, 32.6 vs. 2.5 deaths per 1000 person-years). The burden of congenital anomalies, diseases of the nervous system, and infectious diseases as recorded causes of deaths was higher among live-born children with congenital Zika syndrome than among those without the syndrome.

CONCLUSIONS

The risk of death was higher among live-born children with congenital Zika syndrome than among those without the syndrome and persisted throughout the first 3 years of life. (Funded by the Ministry of Health of Brazil and others.).

Biases arising from linked administrative data for epidemiological research: a conceptual framework from registration to analyses

Linked administrative data offer a rich source of information that can be harnessed to describe patterns of disease, understand their causes and evaluate interventions. However, administrative data are primarily collected for operational reasons such as recording vital events for legal purposes, and planning, provision and monitoring of services. The processes involved in generating and linking administrative datasets may generate sources of bias that are often not adequately considered by researchers. We provide a framework describing these biases, drawing on our experiences of using the 100 Million Brazilian Cohort (100MCohort) which contains records of more than 131 million people whose families applied for social assistance between 2001 and 2018. Datasets for epidemiological research were derived by linking the 100MCohort to health-related databases such as the Mortality Information System and the Hospital Information System. Using the framework, we demonstrate how selection and misclassification biases may be introduced in three different stages: registering and recording of people's life events and use of services, linkage across administrative databases, and cleaning and coding of variables from derived datasets. Finally, we suggest eight recommendations which may reduce biases when analysing data from administrative sources.