COVID-19 death risk predictors in Brazil using survival tree analysis: a retrospective cohort from 2020 to 2022

PURPOSE

This study analyses the survival of hospitalized patients with Severe Acute Respiratory Syndrome (SARS) due to COVID-19 and identifies the risk groups for death due to COVID-19 from the identification of potential interactions between its predictors.

METHODS

This was a retrospective longitudinal study with data from 1,756,917 patients reported in the Influenza Epidemiological Surveillance Information System from 26 February 2020 to 31 December 2022. In this study, all adult and older (≥ 20 years) patients were hospitalized with SARS due to COVID-19, with death as the outcome. Survival tree analysis was used to identify potential interactions between the predictors. A model was built for each year of study.

RESULTS

Hospital lethalitywas 33.2%. The worst survival curve was observed among those who underwent invasive mechanical ventilation and were aged 80 years or older in the three years of the pandemic. Black and brown race/color were predictors of deaths in the years 2020 and 2021 when there was greater demand from the health system due to the greater number of cases.

CONCLUSION

By applying survival tree analysis we identified several numbers of homogeneous subgroups with different risks for mortality from COVID-19. These findings show the effects of wide inequalities of access by the population, requiring effective policies for the reduction and adequate management of the disease.

Spatial analysis of hospital-related mortality due to COVID-19 among children and adolescents in Brazil

The objective was to perform a spatial analysis of the hospital mortality rate (HMR) due to severe acute respiratory syndrome (SARS) attributed to COVID-19 among children and adolescents in Brazil from 2020 to 2021. A cluster method was used to group federal units (FUs) based on HMR. In 2020, clusters with high HMRs were formed by north/northeast FUs. In 2021, there was a reduction in HMR. Clusters with higher rates remained in the N/NE region. Regional differences were observed in the HMR. The findings may reflect social inequalities and access to hospital care, especially in the under 1-year-old age group due to the severity of the disease in this group.

Comparison of beriberi cases in indigenous and non-indigenous people, Brazil, 2013 to 2018

Beriberi is the clinical manifestation of severe and prolonged thiamine (vitamin B1) deficiency. It is a neglected disease that affects low-income populations facing food and nutrition insecurity. The aim of this study was to compare cases of beriberi among indigenous and non-indigenous people in Brazil. We conducted a cross-sectional study using data on cases of beriberi during the period July 2013-September 2018 derived from beriberi notification forms available on the FormSUS platform. Cases in indigenous and non-indigenous patients were compared using the chi-squared test or Fisher's exact test, adopting a significance level of 0.05. A total of 414 cases of beriberi were reported in the country during the study period, 210 of which (50.7%) were among indigenous people. Alcohol consumption was reported by 58.1% of the indigenous patients and 71.6% of the non-indigenous patients (p = 0.004); 71.0% of the indigenous patients reported that they consumed caxiri, a traditional alcoholic drink. Daily physical exertion was reported by 76.1% of the indigenous patients and 40.2% of the non-indigenous patients (p < 0.001). It is concluded that beriberi disproportionately affects indigenous people and is associated with alcohol consumption and physical exertion.

Deaths, crimes and violence not classified as a crime among children and adolescents in Maranhão, Brazil (2014 to 2020)

This study compares temporal trends in violent deaths of children and adolescents and analyzes differences in incidents of violence classified and not classified as a crime. We analyzed data from the Mortality Information System and State of Maranhão Public Security Department for the period 2014 to 2020. Child and adolescent were defined as aged 0-11 and 12-17 years old, respectively. Types of violence were organized according to the groups, subgroups, and types of crimes set out in Brazil's penal code. A total of 1,326 deaths and 8,187 incidents of violence were reported, both of which were more frequent in adolescents. The most frequent types of violence in children and adolescentes, respectively, were: abduction of incapable persons (p < 0.001), abandonment of incapable persons (p = 0.045), rape of vulnerable persons (p = 0.003); homicides (p < 0.001), crimes against individual freedom (p = 0.004), crimes against sexual freedom (p < 0.001), psychological violence (p = 0.034). Domestic violence with bodily harm was more frequent in girls (p < 0.001), while severe bodily harm (p=0.002), homicide (p < 0.001), and harassment (p < 0.001) were more frequent in boys. The findings reveal differences over time in deaths and incidents of violence classified and not classified as crime among both children and adolescents.

Excess deaths from all causes and by COVID-19 in Brazil in 2020

OBJECTIVE

To estimate the 2020 all-cause and COVID-19 excess mortality according to sex, age, race/color, and state, and to compare mortality rates by selected causes with that of the five previous years in Brazil.

METHODS

Data from the Mortality Information System were used. Expected deaths for 2020 were estimated from 2015 to 2019 data using a negative binomial log-linear model.

RESULTS

Excess deaths in Brazil in 2020 amounted to 13.7%, and the ratio of excess deaths to COVID-19 deaths was 0.90. Reductions in deaths from cardiovascular diseases (CVD), respiratory diseases, and external causes, and an increase in ill-defined causes were all noted. Excess deaths were also found to be heterogeneous, being higher in the Northern, Center-Western, and Northeastern states. In some states, the number of COVID-19 deaths was lower than that of excess deaths, whereas the opposite occurred in others. Moreover, excess deaths were higher in men aged 20 to 59, and in black, yellow, or indigenous individuals. Meanwhile, excess mortality was lower in women, in individuals aged 80 years or older, and in whites. Additionally, deaths among those aged 0 to 19 were 7.2% lower than expected, with reduction in mortality from respiratory diseases and external causes. There was also a drop in mortality due to external causes in men and in those aged 20 to 39 years. Moreover, reductions in deaths from CVD and neoplasms were noted in some states and groups.

CONCLUSION

There is evidence of underreporting of COVID-19 deaths and of the possible impact of restrictive measures in the reduction of deaths from external causes and respiratory diseases. The impacts of COVID-19 on mortality were heterogeneous among the states and groups, revealing that regional, demographic, socioeconomic, and racial differences expose individuals in distinct ways to the risk of death from both COVID-19 and other causes.

Autoregressive spatial modeling of possible cases of dengue, chikungunya, and Zika in the capital of Northeastern Brazil

INTRODUCTION:

Dengue, chikungunya, and Zika are a growing global health problem. This study analyzed the spatial distribution of dengue, chikungunya, and Zika cases in São Luís, Maranhão, from 2015 to 2016 and investigated the association between socio-environmental and economic factors and hotspots for mosquito proliferation.

METHODS:

This was a socio-ecological study using data from the National Information System of Notifiable Diseases. The spatial units of analysis were census tracts. The incidence rates of the combined cases of the three diseases were calculated and smoothed using empirical local Bayes estimates. The spatial autocorrelation of the smoothed incidence rate was measured using Local Moran's I and Global Moran's I. Multiple linear regression and spatial autoregressive models were fitted using the log of the smoothed disease incidence rate as the dependent variable and socio-environmental factors, demographics, and mosquito hotspots as independent variables.

RESULTS:

The findings showed a significant spatial autocorrelation of the smoothed incidence rate. The model that best fit the data was the spatial lag model, revealing a positive association between disease incidence and the proportion of households with surrounding garbage accumulation.

CONCLUSIONS:

The distribution of dengue, chikungunya, and Zika cases showed a significant spatial pattern, in which the high-risk areas for the three diseases were explained by the variable "garbage accumulated in the surrounding environment,” demonstrating the need for an intersectoral approach for vector control and prevention that goes beyond health actions.

Beriberi in Brazil: A Disease That Affects Indigenous People

BACKGROUND

Beriberi is the clinical manifestation of thiamine deficiency. It is multicausal and typically associated with poverty and food insecurity among vulnerable populations, such as indigenous people.

OBJECTIVE

The objective of this study was to carry out a spatial analysis of reported cases of beriberi among indigenous people in Brazil.

METHODS

Cross-sectional study using time series data on suspected cases of beriberi reported to the Ministry of Health via the FormSUS between July 2013 and September 2018. Indigenous villages were georeferenced, and Kernel density estimation was used to identify patterns of the spatial distribution of beriberi cases.

RESULTS

A total of 414 cases of beriberi were reported in the country of which 210 (50.7%) were indigenous people. All the cases in indigenous people occurred in states located in the Legal Amazon (Maranhão, Roraima, and Tocantins). Kernel density estimation showed high-density areas in Tocantins and Roraima.

CONCLUSIONS

This is the first nationwide study of reported cases of beriberi. The findings can be used to guide actions that contribute to the monitoring and prevention of beriberi among indigenous people.

Congenital Zika syndrome: Growth, clinical, and motor development outcomes up to 36 months of age and differences according to microcephaly at birth

BACKGROUND

Little is known regarding the developmental consequences of congenital Zika syndrome (CZS) without microcephaly at birth. Most previously published clinical series were descriptive and they had small sample sizes.

STUDY DESIGN

We conducted a cohort study to compare the growth, clinical, and motor development outcomes for 110 children with CZS born with and without microcephaly up to their third birthday. Ninety-three had their head circumference (HC) at birth abstracted and they did not have hypertensive hydrocephalus at birth, where 61 were born with microcephaly and 32 without.

RESULTS

The HC z-scores decreased steeply from birth to six months of age, i.e., from -3.77 to -6.39 among those with microcephaly at birth and from -1.03 to -3.84 among those without. Thus, at 6 months of age, the mean HC z-scores for children born without microcephaly were nearly the same as those for children born with microcephaly. Children born without microcephaly were less likely to have brain damage, ophthalmic abnormalities, and drug-resistant epilepsy, but the differences in many conditions were not statistically significant.

CONCLUSIONS

Children born without microcephaly were only slightly less likely to present severe neurologic impairment and to develop postnatal-onset microcephaly, and some of the original differences between the groups tended to dissipate with age.

Bolsa Família program and incomplete childhood vaccination in two Brazilian cohorts

OBJECTIVE:

To estimate the effect of being a beneficiary of the Bolsa Família Program (BFP) in the vaccination of children aged 13 to 35 months.

METHODS:

Our study was based on all birth records of residents of Ribeirão Preto (SP) and probabilistic sampling with 1/3 of the births of residents of São Luís (MA), selecting low-income children, born in 2010, belonging to the cohorts Brazilian Ribeirão Preto and São Luís Birth Cohort Studies and eligible for the Bolsa Família program. The information of Cadastro Único (CadÚnico – Single Registry) was used to categorize the receipt of benefit from the BFP (yes or no). The final sample consisted of 532 children in Ribeirão Preto and 1,229 in São Luís. The outcome variable was a childhood vaccine regimen, constructed with BCG, tetravalent, triple viral, hepatitis B, poliomyelitis, rotavirus and yellow fever vaccines. The adjustment variables were: economic class, mother's schooling and mother's skin color. Children with monthly per capita family income of up to R$ 280.00 and/or economic class D/E were considered eligible for the benefit of the BFP. A theoretical model was constructed using a directed acyclic graph to estimate the effect of being a beneficiary of the BFP in the vaccination of low-income children. In the statistical analyses, weighing was used by the inverse of the probability of exposure and pairing by propensity score.

RESULTS:

Considering a monthly per capita family income of up to R$ 280.00, being a beneficiary of the BFP had no effect on the childhood vaccination schedule, according to weighing by the inverse of the probability of exposure (SL-coefficient: −0.01; 95%CI −0.07 to 0.04; p = 0.725 and RP-coefficient: 0.04; 95%CI −0.02 to 0.10; p = 0.244) and pairing by propensity score (SL-coefficient: −0.01; 95%CI −0.07 to 0.05; p = 0.744 and RP-coefficient: 0.04; 95%CI −0.02 to 0.10; p = 0.231).

CONCLUSIONS:

The receipt of the benefit of the BFP did not influence childhood vaccination, which is one of the conditionalities of the program. This may indicate that this conditionality is not being adequately monitored.

Characteristics of basic health units and detection of tuberculosis cases

INTRODUCTION

Tuberculosis (TB) is an infectious and contagious disease caused by Mycobacterium tuberculosis. TB emerged in the 21st century as an unsolved public health problem. This study aimed to analyze the relationship between the characteristics of basic health units (BHUs) and the number of TB cases detected in Maranhão, Brazil.

METHODS

An ecological, analytical study was conducted using the municipalities in the state of Maranhão as the unit of analysis. Data regarding the number of detected TB cases was obtained from the Sistema de Informação de Agravos de Notificação database, and the characteristics of the BHUs were obtained from the first cycle of data collection for the Program to Improve Access and Quality of Basic Care. The BHU structure was classified as adequate (80%-100%), partially adequate (60%-79%), poorly adequate (40%-59%), or inadequate (<40%) according to the presence of specified items. The number of BHUs per municipality in each adequacy category was estimated. Inflated Poisson regression analysis was performed to estimate the incidence density ratios (IDRs) and the 95% confidence intervals (95% CIs).

RESULTS

Municipalities with a higher level of BHU adequacy had a higher number of detected TB cases (IDR = 1.61, 95% CI: 1.01-2.60).

CONCLUSIONS

Better structured health services in primary care may be associated with better detection and/or notification of TB cases.

Spatial analysis of probable cases of dengue fever, chikungunya fever and zika virus infections in Maranhao State, Brazil

Dengue fever, chikungunya fever, and zika virus infections are increasing public health problems in the world, the last two diseases having recently emerged in Brazil. This ecological study employed spatial analysis of probable cases of dengue fever, chikungunya fever, and zika virus infections reported to the National Mandatory Reporting System (SINAN) in Maranhao State from 2015 to 2016. The software GeoDa version 1.10 was used for calculating global and local Moran indices. The global Moran index identified a significant autocorrelation of incidence rates of dengue (I=0.10; p=0.009) and zika (I=0.07; p=0.03). The study found a positive spatial correlation between dengue and the population density (I=0.31; p<0.001) and a negative correlation with the Performance Index of Unified Health System (PIUHS) by basic care coverage (I=-0.08; p=0.01). Regarding chikungunya fever, there were positive spatial correlations with the population density (I=0.06; p=0.03) and the Municipal Human Development Index (MHDI) (I=0.10; p=0.002), and a negative correlation with the Gini index (I=-0.01; p<0.001) and the PIUHS by basic care coverage (I=-0.18; p<0.001). Lastly, we found positive spatial correlations between Zika virus infections and the population density (I=0.13; p=0.005) and the MHDI (I=0.12; p<0.001), as well as a negative correlation with the Gini index (I=-0.11; p<0.001) and the PIUHS by basic care coverage (I=-0.05; p=0.03). Our results suggest that several socio-demographic factors influenced the occurrence of dengue fever, chikungunya fever, and zika virus infections in Maranhao State.

Incomplete childhood immunization with new and old vaccines and associated factors: BRISA birth cohort, São Luís, Maranhão State, Northeast Brazil

This study estimated the percentages of incomplete immunization with new vaccines and old vaccines and associated factors in children 13 to 35 months of age belonging to a birth cohort in São Luís, the capital of Maranhão State, Brazil. The sample was probabilistic, with 3,076 children born in 2010. Information on vaccination was obtained from the Child's Health Card. The new vaccines, namely those introduced in 2010, were meningococcal C and 10-valent pneumococcal, and the old vaccines, or those already on the childhood immunization schedule, were BCG, hepatitis B, human rotavirus, polio, tetravalent (diphtheria, tetanus, pertussis, Haemophilus influenzae b), yellow fever, and triple viral (measles, mumps, rubella). The study used hierarchical modeling and Poisson regression with robust variance. Prevalence ratios (PR) and 95% confidence intervals (95%CI) were calculated. Incomplete immunization was higher with new vaccines (51.1%) than with old vaccines (33.2%). Children 25 to 35 months of age (PR = 1.27; 95%CI: 1.14-1.41) and those in economic classes D/E (PR = 1.20; 95%CI: 1.06-1.35) were only significantly associated with new vaccines; low maternal schooling (PR = 1.58; 95%CI: 1.21-2.06), unavailability of outpatient and/or hospital care for the child (PR = 1.20; 95%CI: 1.04-1.38), and unavailability of the vaccine in health services (PR: 1.28; 95%CI: 1.12-1.46) were only associated with old vaccines. Immunization strategies should consider the vulnerability of older preschool-age children and those belonging to classes D and E, especially when new vaccines are introduced, as well as children of mothers with low schooling. Strategies should also address problems with the availability of health services and vaccines.

Early Growth and Neurologic Outcomes of Infants with Probable Congenital Zika Virus Syndrome

We report the early growth and neurologic findings of 48 infants in Brazil diagnosed with probable congenital Zika virus syndrome and followed to age 1-8 months. Most of these infants had microcephaly (86.7%) and craniofacial disproportion (95.8%). The clinical pattern included poor head growth with increasingly negative z-scores, pyramidal/extrapyramidal symptoms, and epilepsy.

Spatial-temporal analysis of dengue deaths: identifying social vulnerabilities

INTRODUCTION

Currently, dengue fever, chikungunya fever, and zika virus represent serious public health issues in Brazil, despite efforts to control the vector, the Aedes aegypti mosquito.

METHODS:

This was a descriptive and ecological study of dengue deaths occurring from 2002 to 2013 in São Luis, Maranhão, Brazil. Geoprocessing software was used to draw maps, linking the geo-referenced deaths with urban/social data at census tract level.

RESULTS:

There were 74 deaths, concentrated in areas of social vulnerability.

CONCLUSIONS:

The use of geo-technology tools pointed to a concentration of dengue deaths in specific intra-urban areas.