Prognostic value of Chagas heart disease on short- and long-term clinical outcomes in patients hospitalized for COVID-19.

Background: Immunological similarities led us to explore potential interactions between Chagas heart disease (CHD) and coronavirus disease 2019 (COVID-19). We evaluated CHD's impact on the short- and long-term clinical courses of COVID-19 patients.

Methods: The CHD group comprised consecutive hospitalized patients (March 2020-March 2022), while the controls were selected through genetic matching based on COVID complications predictors. Cox proportional hazards models were used to assess the predictive value of CHD.

Results: Among 114 patients (50.9% male, 82.5% Caucasian, median age 66 y), prevalent comorbidities included cardiovascular diseases (84.2%) and type 2 diabetes (15.8%). Over a 22-month follow-up, no significant difference in the composite outcome (death and decompensated heart failure) was found between CHD patients (68.4%) and controls (72.6%, p=0.709). In-hospital and post-discharge clinical courses showed similarities in presentation, exams, respiratory support, long-COVID manifestations and death (p>0.05). Cox models identified age (every 10 y) (hazard ratio [HR] 1.70 [95% confidence interval {CI} 1.31 to 2.20], p<0.001) and normal lymphocyte count (800-1600/mm3) (HR 0.94 [95% CI 0.89 to 0.98], p=0.007) as independent predictors of mortality.

Conclusions: CHD does not significantly impact clinical presentation, in-hospital outcomes or long-COVID manifestations. Age and lymphocyte count are independent predictors of mortality, emphasizing their prognostic significance in COVID-19 complications, regardless of comorbidities.