Chagas Disease (CD) in the Jequitinhonha Valley represents a significant public health concern, substantially impacting patients' lives, affecting their social participation and overall quality of life. However, categorizing these impacts presents considerable complexities and challenges.

This study aims to develop the first stage of a Core Set of the International Classification of Functioning, Disability, and Health (ICF) for CD. This Core Set aims to better understand CD's functional implications and support decision-making in epidemiology and rehabilitation.

A literature review and a focus group study were conducted to identify functional aspects of disability caused by CD in adults (> 18 years) of both sexes. Published studies from the PubMed and SciELO databases were reviewed, and after excluding duplicates and studies that did not meet the inclusion criteria, 27 studies were selected for analysis. Concurrently, six focus groups were conducted with 16 adults (mean age: 67 ± 8 years) diagnosed with the cardiac form of CD, aiming to identify the most relevant functional consequences in this population. The concepts identified in the literature review and those emerging from the focus group discussions were subsequently mapped to the categories of the ICF checklist by two independent researchers.

The literature review identified 310 relevant outcomes, while 180 outcomes emerged from the focus groups. These outcomes were mapped to 42 and 41 second-level categories of the ICF checklist, respectively. The most frequently identified categories in the literature review were: b130 (Energy and drive functions), b152 (Emotional functions), b410 (Heart functions), s410 (Cardiovascular system), e110 (Products and substances for personal consumption, such as food and medicine), and e580 (Health services, systems, and policies). In contrast, the most frequently mentioned categories by the patients in the focus groups were: b134 (Sleep functions), b152 (Emotional functions), b280 (Pain), d930 (Religion and spirituality), and e310 (Immediate family). The results reveal a disparity between the clinical perspectives and the experiences reported by patients with CD. While the literature review highlighted biological and cardiovascular outcomes, the focus group patients emphasized the disease's emotional, social, and spiritual dimensions, such as sleep, pain, family, and spirituality.

This suggests that, in addition to biological aspects, patients experience CD holistically, significantly impacting their quality of life.

These findings highlight the importance of incorporating patient perspectives in developing a Core Set of the ICF for CD.