The Burden of Chagas Disease in the Contemporary World: The RAISE Study

Chagas disease (ChD), a Neglected Tropical Disease, has witnessed a transformative epidemiological landscape characterized by a trend of reduction in prevalence, shifting modes of transmission, urbanization, and globalization. Historically a vector-borne disease in rural areas of Latin America, effective control measures have reduced the incidence in many countries, leading to a demographic shift where most affected individuals are now adults. However, challenges persist in regions like the Gran Chaco, and emerging oral transmission in the Amazon basin adds complexity. Urbanization and migration from rural to urban areas and to non-endemic countries, especially in Europe and the US, have redefined the disease's reach. These changing patterns contribute to uncertainties in estimating ChD prevalence, exacerbated by the lack of recent data, scarcity of surveys, and reliance on outdated models. Besides, ChD's lifelong natural history, marked by acute and chronic phases, introduces complexities in diagnosis, particularly in non-endemic regions where healthcare provider awareness is low. The temporal dissociation of infection and clinical manifestations, coupled with underreporting, has rendered ChD invisible in health statistics. Deaths attributed to ChD cardiomyopathy often go unrecognized, camouflaged under alternative causes. Understanding these challenges, the RAISE project aims to reassess the burden of ChD and ChD cardiomyopathy. The project is a collaborative effort of the World Heart Federation, Novartis Global Health, the University of Washington's Institute for Health Metrics and Evaluation, and a team of specialists coordinated by Brazil's Federal University of Minas Gerais. Employing a multidimensional strategy, the project seeks to refine estimates of ChD-related deaths, conduct systematic reviews on seroprevalence and prevalence of clinical forms, enhance existing modeling frameworks, and calculate the global economic burden, considering healthcare expenditures and service access. The RAISE project aspires to bridge knowledge gaps, raise awareness, and inform evidence-based health policies and research initiatives, positioning ChD prominently on the global health agenda.

Excess Mortality due to natural causes among whites and blacks during the COVID-19 pandemic in Brazil

INTRODUCTION

Excess Mortality by all causes considers deaths directly related to COVID-19 and those attributed to conditions caused by the pandemic. When stratified by social dimensions, such as race/color, it allows for the evaluation of more vulnerable populations. The study estimated the excess mortality by natural causes, separating the white and black populations in 2020.

METHODS

Public civil registration data on deaths observed in 2020, corrected for under registration, were used. The expected number of deaths was estimated based on the mortality rates observed in 2019, applied to the estimated population in 2020. The difference between the values expected and observed and the proportion of excess was considered the excess mortality.

RESULTS

The present study found an excess of 270,321 deaths (22.2% above the expected) in 2020. Every state of Brazil reported deaths above the corresponding expected figure. The excess was higher for men (25.2%) than for women (19.0%). Blacks showed an excess of 27.8%, as compared to whites at 17.6%. In both sexes and all age groups, excess was higher in the black population, especially in the South, Southeast, and Midwest regions. São Paulo, the largest in population number, had twice as much excess death in the black population (25.1%) than in the white population (11.5%).

CONCLUSIONS

The present study showed racial disparities in excess mortality during the COVID-19 pandemic in Brazil. The higher excess found for the black suggests an intrinsic relationship with the socioeconomic situation, further exposing the Brazilian reality, in which social and structural inequality is evident.

Covid Adult Mortality in Brazil: An Analysis of Multiple Causes of Death

Objective

This study aimed to analyze the chain of events and contributing causes associated with COVID-19 adult mortality (30–69 years old), based on qualified data on CoD from three Brazilian capitals cities, Belo Horizonte, Salvador, and Natal, in 2020.

Methods

Data of all deaths among residents in the three capitals in 2020 were provided by these municipalities' routine Mortality Information System (SIM). Mentions B34.2 with the markers U07.1 and U07.2 in the death certificate identified COVID-19 deaths. We used a multiple-cause-of-death approach better to understand the complexity of the morbid process of COVID-19. Conditions that appeared more frequently in the same line or above the COVID-19 mentions in the death certificate were considered a chain-of-event. Conditions that occurred more often after the codes for COVID-19 were considered as contributing.

Results

In 2020, 7,029 records from COVID-19 as the underlying cause of death were registered in SIM in the three capitals. Among these, 2,921 (41.6%) were deceased between 30 and 69 years old, representing 17.0% of deaths in this age group. As chain-of-events, the most frequent conditions mentioned were sepsis (33.4%), SARS (32.0%), acute respiratory failure (31.9%), unspecified lower respiratory infections (unspecified pneumonia) (20.1%), and other specified respiratory disorders (14.1%). Hypertension (33.3%), diabetes unspecified type (21.7%), renal failure (12.7%), obesity (9.8%), other chronic kidney diseases (4.9%), and diabetes mellitus type 2 (4.7%) were the most frequent contributing conditions. On average, 3.04 conditions were mentioned in the death certificate besides COVID-19. This average varied according to age, place of death, and capital.

Conclusion

The multiple-cause analysis is a powerful tool to better understand the morbid process due to COVID-19 and highlight the importance of chronic non-communicable diseases as contributing conditions.

Garbage codes as causes of death and quality of mortality statistics in Belo Horizonte, Brazil

Background

Quality of cause-of-death information is fundamental for health planning. Traditionally, this quality has been assessed by the analysis of ill-defined causes from chapter XVIII of the International Classification of Diseases - 10th revision (ICD-10). However, studies have considered other useless diagnoses for public health purposes, defined, in conjunction with ill-defined causes, as garbage codes (GC). In Brazil, despite the high completeness of the Mortality Information System, approximately 30% of deaths are attributable to GCs. This study aims to analyze the frequency of GCs in Belo Horizonte municipality, the capital of Minas Gerais state, Brazil.

Methods

Data of deaths from 2011 to 2013 in Belo Horizonte were analyzed. GCs were classified according to the GBD 2015 study list. These codes were classified in: a) GCs from chapter XVIII of ICD-10 (GC-R), and b) GC from other chapters of ICD-10 (GC-nonR). Proportions of GC were calculated by sex, age, and place of occurrence.

Results

In Belo Horizonte, from the total of 44,123 deaths, 5.5% were classified as GC-R. The majority of GCs were GC-nonR (25% of total deaths). We observed a higher proportion of GC in children (1 to 4 years) and in people aged over 60 years. GC proportion was also higher in females, except in the age-groups under 1 year and 30-59 years. Home deaths (n = 7,760) had higher proportions of GCs compared with hospital deaths (n = 30,182), 36.9% and 28.7%, respectively. The leading GCs were the GC-R other ill-defined and unspecified causes of death (ICD-10 code R99)), and the GCs-nonR unspecified pneumonia (J18.9), unspecified stroke (I64), and unspecified septicemia (A41.9).

Conclusions

Analysis of GCs is essential to evaluate the quality of mortality information.

Key messages

Analysis of ill-defined causes (GC-R) is not sufficient to evaluate the quality of information on causes of death. Causes of death analysis should consider the total GC, in order to advance the discussion and promote adequate intervention on the quality of mortality statistics.

Investigation of hospital deaths declared as garbage codes in Belo Horizonte, Brazil, in 2017

Background

Improving the quality of causes of death (COD) is vital for defining adequate public policies. In Brazil, one third of deaths are reported as having a cause that is not useful for public health analysis of cause-of-death data, the so-called garbage codes (GC). The investigation of these deaths is one of the strategies that could improve the quality of mortality statistics in the country.

Methods

For all GCs identified in 2017 in the routine mortality information system from Belo Horizonte city, Brazil, municipal health professionals collected information about the final disease obtained from hospital records or autopsies in a standardized form. A trained physician analyzed this information and filled in a new death certificate (DC). The DC that originally showed a GC as an underlying COD was categorized into GC reclassified when the garbage cause changed to a specific cause after investigation. Causes of death derived from the reclassified GCs were analyzed to assess the impact on the mortality profile before and after the investigation.

Results

In Belo Horizonte, 1,395 deaths out of 3,038 registered as garbage codes were investigated, with a 35% reduction in deaths due to these causes. There was an increase in deaths from ischemic heart diseases, Alzheimer's disease, chronic obstructive pulmonary disease, hemorrhagic and ischemic stroke, and violence.

Conclusions

The investigation of deaths from garbage codes modified the mortality profile and improved its quality, providing direction for more assertive public health policies. Strategies for training physicians to report specific causes of death is another strategy that could improve the quality of mortality data.

Key messages

This study proved to be a feasible strategy in improving the quality of causes of death in mortality statistics and should be incorporated into the surveillance routine activities in Brazil. The evaluation of the GC investigation is an important instrument in helping management of health interventions aiming at better quality of information and more qualified health services.

Improving the usefulness of mortality data in Brazil: reclassification of ill-defined causes of death

Background

Garbage codes (GC) among registered causes of death can bias mortality analysis. In Brazil, more than one million deaths occurred annually in 2006-2017 and around 100,000 deaths per year were originally attributed to GC ill-defined causes of death (IDCD) in the Mortality Information System (SIM - Sistema de Informação sobre Mortalidade). To provide more accurate cause-of-death analysis, routine investigations of IDCD in the health surveillance system have been implemented in the country since 2005. The objective of this study was to analyze specific underlying causes for deaths originally assigned as IDCD in the SIM in 2006-2017.

Methods

For all IDCD (ICD codes from chapter 18, or R-codes) identified in the SIM, municipal health professionals collected information about the final disease obtained from hospital records, autopsies, forms of family health teams, and home investigation. Proportions of reclassified deaths by cause-specific mortality fractions (CSMF) derived from the reclassified IDCD by age and four calendar periods were analyzed to assess specific causes detected after investigation.

Results

A high proportion of deaths due to IDCD was investigated in 2006-2017 (32%). From a total of 257,367 IDCD reclassified, chronic diseases (56.6%), injuries (7.2%), and infectious (5.2%) or neonatal, maternal, malnutrition (1.7%) were the underlying causes detected among IDCD. Neonatal-related conditions, interpersonal violence, ischemic heart disease and stroke were the leading causes detected in the age groups 0-9 years, 10-29 years, 30-69 years, 70 years and over, respectively.

Conclusions

High proportions of IDCD reassigned to more informative causes after review indicate the success of this approach to correct misclassification in the SIM, an initiative that should be maintained. Training physicians on death certification along with better quality of medical care and access to health services would lead to further improvement.

Key messages

Investigation of IDCD as part of routine data collection on a large scale as had occurred in Brazil in 2006-2017 is an innovative approach to strengthen population-level mortality statistics. In addition to reducing the proportions of IDCD by their reclassification into specific causes, this initiative opens up the prospect of using these results for redistributing remaining cases of IDCD.

Cause-specific mortality for 249 causes in Brazil and states during 1990-2015: a systematic analysis for the global burden of disease study 2015

Background

Reliable data on cause of death (COD) are fundamental for planning and resource allocation priorities. We used GBD 2015 estimates to examine levels and trends for the leading causes of death in Brazil from 1990 to 2015.

Methods

We describe the main analytical approaches focused on both overall and specific causes of death for Brazil and Brazilian states.

Results

There was an overall improvement in life expectancy at birth from 1990 to 2015, but with important heterogeneity among states. Reduced mortality due to diarrhea, lower respiratory infections, and other infectious diseases contributed the most for increasing life expectancy in most states from the North and Northeast regions. Reduced mortality due to cardiovascular diseases was the highest contributor in the South, Southeast, and Center West regions. However, among men, intentional injuries reduced life expectancy in 17 out of 27 states. Although age-standardized rates due to ischemic heart disease (IHD) and cerebrovascular disease declined over time, these remained the leading CODs in the country and states. In contrast, leading causes of premature mortality changed substantially - e.g., diarrheal diseases moved from 1st to 13th and then the 36th position in 1990, 2005, and 2015, respectively, while violence moved from 7th to 1st and to 2nd. Overall, the total age-standardized years of life lost (YLL) rate was reduced from 1990 to 2015, bringing the burden of premature deaths closer to expected rates given the country’s Socio-demographic Index (SDI). In 1990, IHD, stroke, diarrhea, neonatal preterm birth complications, road injury, and violence had ratios higher than the expected, while in 2015 only violence was higher, overall and in all states, according to the SDI.

Conclusions

A widespread reduction of mortality levels occurred in Brazil from 1990 to 2015, particularly among children under 5 years old. Major shifts in mortality rates took place among communicable, maternal, neonatal, and nutritional disorders. The mortality profile has shifted to older ages with increases in non-communicable diseases as well as premature deaths due to violence. Policymakers should address health interventions accordingly.

Electronic supplementary material

The online version of this article (10.1186/s12963-017-0156-y) contains supplementary material, which is available to authorized users.

Ill-defined causes of death in Brazil: a redistribution method based on the investigation of such causes

OBJECTIVE

To propose a method of redistributing ill-defined causes of death (IDCD) based on the investigation of such causes.

METHODS

In 2010, an evaluation of the results of investigating the causes of death classified as IDCD in accordance with chapter 18 of the International Classification of Diseases (ICD-10) by the Mortality Information System was performed. The redistribution coefficients were calculated according to the proportional distribution of ill-defined causes reclassified after investigation in any chapter of the ICD-10, except for chapter 18, and used to redistribute the ill-defined causes not investigated and remaining by sex and age. The IDCD redistribution coefficient was compared with two usual methods of redistribution: a) Total redistribution coefficient, based on the proportional distribution of all the defined causes originally notified and b) Non-external redistribution coefficient, similar to the previous, but excluding external causes.

RESULTS

Of the 97,314 deaths by ill-defined causes reported in 2010, 30.3% were investigated, and 65.5% of those were reclassified as defined causes after the investigation. Endocrine diseases, mental disorders, and maternal causes had a higher representation among the reclassified ill-defined causes, contrary to infectious diseases, neoplasms, and genitourinary diseases, with higher proportions among the defined causes reported. External causes represented 9.3% of the ill-defined causes reclassified. The correction of mortality rates by the total redistribution coefficient and non-external redistribution coefficient increased the magnitude of the rates by a relatively similar factor for most causes, contrary to the IDCD redistribution coefficient that corrected the different causes of death with differentiated weights.

CONCLUSIONS

The proportional distribution of causes among the ill-defined causes reclassified after investigation was not similar to the original distribution of defined causes. Therefore, the redistribution of the remaining ill-defined causes based on the investigation allows for more appropriate estimates of the mortality risk due to specific causes.

Trends in mortality due to diabetes in Brazil, 1996-2011

BACKGROUND

Over recent decades, Brazilian mortality registration has undergone increasing improvement in terms of completeness and quality in cause of death reporting. These improvements, however, complicate the description of mortality trends over this period. We aim to characterize the trend in diabetes mortality in Brazil and its five regions in adults (30-69 years), from 1996 to 2011 after corrections for underreporting of deaths and redistribution of ill-defined causes and "garbage codes".

METHODS

Starting with official data from the Brazilian Mortality Information System (SIM) for adults aged 30-69 in the period 1996 to 2011 for diabetes (ICD-10 codes E10-14), we redistributed garbage codes using methods based on the Global Burden of Disease Study (2010), redistributed ill-defined causes based on recent Brazilian investigations of similar cases and corrected for underreporting using official estimates of deaths.

RESULTS

With these corrections, age-standardized mortality fell approximately 1.1 %/year for men and 2.2 %/year for women from 1996 to 2011. The rate of decline first accelerated and then decelerated, reaching stable rates in men and minimal declines in women from 2005 onward. Regional inequalities decreased during the period in both relative and absolute terms.

CONCLUSION

Mortality due to diabetes declined in Brazil from 1996 to 2011, minimally in men and considerably in women. The lesser declines in recent years may reflect the increasing prevalence of diabetes, and suggest that current efforts to prevent diabetes and minimize the impact of its complications need to be reinforced to ensure that declines will continue.