Chagas incidence and mortality cyclicities: A global burden of disease evaluation

Chagas is a neglected tropical disease with a significant socioeconomic impact. Although several studies have focused on evaluating its epidemiological aspects, the cyclical behavior of its incidence and mortality remains poorly explored; thereto, this study aimed to evaluate them.

This was a retrospective with populational approach study that employed data from the Global Burden of Disease. The cyclicity was evaluated by using the Fast Fourier Transform to fit cyclical sinusoidal models for every period between 2 and 40 years in 0.1-year increments. Each model was manually evaluated by its p-value of joint sine-cosine term, its semi-amplitude, its 95% Confidence Interval, and how well it followed the graphical behavior of the reference source. Data were stratified by age group, gender, and country by using R software 4.4.2.

Overall, cycles between 20 and 30 years were identified, with incidence and mortality cyclicity displaying alignment trends. Shorter cycle lengths were observed in the 0-14 years age group compared to other age groups. Gender differences were minor noted. Between the evaluated countries, Mexico and Argentina tend to present shorter mortality cycles in comparison with their incidence cycles.

Although there are some specificities in the Chagas cyclicity, there is a general tendency of alignment among its cycles. Recognizing these patterns, derived from a complex interplay between biological, economic, social, and political variables, is fundamental to optimizing the timing and targeting of public health interventions on the issue.