Chagas disease and mortality in a community-based cohort in Colombia: evidence for age-dependent effect modification

BACKGROUND:

Chagas disease (CD), caused by Trypanosoma cruzi, is a leading cause of cardiomyopathy in Latin America. Community-based prospective data on the CD-mortality association remain scarce.

METHODS:

We analysed the ANTORCHA prospective cohort, enrolling individuals from T. cruzi-endemic communities in Santander, Colombia (2015-2025). The primary exposure was serologically confirmed CD; the primary outcome was all-cause mortality. Cox proportional hazards models with hierarchical adjustment and restricted mean survival time (RMST) were used.

RESULTS:

Among 1509 participants (314 Chagas positive), 81 deaths occurred over a median follow-up of 5.6 y. After full multivariate adjustment, CD was not associated with overall mortality (hazard ratio [HR] 1.02 [95% confidence interval {CI} 0.61 to 1.72]). A significant age-dependent interaction was identified (p=0.007): CD was independently associated with increased mortality among participants <60 y of age (HR 4.96 [95% CI 1.80 to 13.71]) but not among those ≥60 y of age (HR 0.73 [95% CI 0.43 to 1.22]). RMST analysis confirmed an absolute survival loss of 121 d at approximately 10 y of follow-up in the younger subgroup (p=0.02).

CONCLUSIONS:

In this community-based cohort, CD was independently associated with markedly elevated mortality among adults <60 y of age. Younger T. cruzi-positive individuals warrant intensified cardiovascular surveillance.