Following the largest historical cohort study ever conducted in Brazil, which suggested a link between Chagas disease and ischemic stroke, researchers from the Federal Fluminense University have described the profile of patients who are predisposed to stroke recurrence because of the combination of these two medical conditions. Cardiovascular risk, age, and gender influence stroke recurrence in patients with stroke history and Chagas disease, as detailed in an article published in Cerebrovascular Diseases.

Understanding the epidemiologic history of patients with Chagas disease who have had a stroke contributed to more assertive case monitoring, thus enabling the most appropriate treatment for patients at a higher risk for stroke recurrence. Data from the Epidemiological Bulletin published in 2022 by Brazil’s Ministry of Health indicated that there are between 1.9 and 4.6 million people with Chagas disease in Brazil. Over 10 years, an average of 4000 deaths from the disease have been recorded per year.

According to the authors of the article, “there remains a noticeable dearth of comprehensive epidemiological studies investigating” the relationship between Chagas disease and ischemic stroke. Considering the implications that both diseases have for public health, investigators conducted a survey to address a critical research gap. The work derived from the doctoral thesis of neurologist Vinicius Montanaro, MD, PhD, of the SARAH network of Rehabilitation Hospitals in Brasília, Brazil. Montanaro collaborated with colleagues from study centers across Brazil to retrieve and analyze patient records and exams.

Risk Factors and Comorbidities

The study centers participating in the research were the Albert Einstein Hospital, the University of São Paulo, the Federal University of Bahia, the Risoleta Tolentino Neves Hospital, the Federal University of Minas Gerais, the Federal University of Pernambuco, and the SARAH Rehabilitation Hospital. The facilities were located in urban and rural areas. The idea was to obtain a representative sample of the social and demographic diversity of the Brazilian population and Chagas disease cases.

Researchers conducted a retrospective analysis of medical records and exams of 499 patients older than 18 years who were followed in these centers from January 2009 to December 2016. The study considered patients diagnosed with Chagas disease confirmed by two serological tests and stroke confirmed by CT or MRI. Demographic factors such as gender and age and cardiovascular risk were evaluated.

The group found that cardiovascular risk factors were prevalent among patients with Chagas disease. About 81% of study participants were hypertensive, 56% had dyslipidemia, and 25% had diabetes. The recurrence rate of stroke in the evaluated individuals was 29.7%. Overall, 56% of patients had cardioembolic stroke of undetermined cause. Another finding was that women had an 83% higher chance of stroke recurrence.

Researchers suggested that hormonal factors and contraceptive use could explain the increased risk among women.

Given the socioeconomic characteristics and limited access to health resources of this population, some variables were not available at all centers, according to the authors.

“Chagas disease patients come from socially vulnerable places, making follow-up difficult,” Montanaro told the Medscape Portuguese edition.

Treatment

The study suggested that controlling risk factors and comorbidities helped prevent strokes in patients with Chagas disease.

“Now we know which patients we should pay more attention to, to the point of having a more adequate etiologic investigation to diagnose cardioembolic etiology and also to perform more precise secondary prophylaxis to avoid stroke recurrence, which has a worse functional outcome and higher mortality rate,” explained Montanaro.

The research pointed to a high recurrence rate of stroke among patients diagnosed with cardioembolism. One of the potential explanations is the abundance of embolic stroke of undetermined origin in the sample. This prevalence results from incomplete etiologic investigation, the researchers pointed out. Another observation is that age acted as a protective factor: Younger patients had fewer cardiac lesions. The use of anticoagulants also contributed to reducing the risk for stroke recurrence. This finding raised the question of the best indication for prophylactic treatment for patients with a history of Chagas disease and ischemic stroke.

A new study aiming to analyze epidemiological issues to evaluate the most appropriate secondary prophylaxis depending on the diagnosis, whether cardioembolic or undefined, is already underway, said Montanaro. The goal is to determine the best strategy for reducing the risk for stroke.

This story was translated from the Medscape Portuguese edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.