Risk factors for severe COVID-19 outcomes in LATAM countries in the post-vaccination era: an analysis of national surveillance data in Argentina, Brazil, Colombia, and Mexico.

BACKGROUND

Identifying cases at higher risk for severe COVID-19 outcomes is essential for tailoring interventions for prevention and treatment. We aimed to determine the factors related to hospitalisation, intensive care unit (ICU) admission, use of ventilatory support, and mortality in four Latin American countries.

METHODS

We conducted a retrospective study using national COVID-19 surveillance databases from Argentina, Brazil, Colombia, and Mexico, covering the period from January 2021 to December 2022. We used multivariate logistic regression models to identify factors associated with hospitalisation, ICU admission, ventilatory support, and death, adjusting for confounding variables.

RESULTS

We included 34 955 384 confirmed cases in the analysis. Age and sex were significantly associated with increased odds of all outcomes. For hospitalisation, in cases aged >85 years, the odds ratio (OR) for hospitalisation ranged from 26.46 (95% confidence interval (CI) = 25.67-27.28) in Mexico to 2763.87 (95% CI = 2644.40-2888.73) in Brazil, and for males, it ranged from 1.42 (95% CI = 1.41-1.43) in Colombia to 1.77 (95% CI = 1.76-1.78) in Brazil. Indigenous race was significantly associated with higher odds of hospitalisation (ORs ranging from 1.26 to 1.98) and death (ORs ranging from 1.05 to 1.84). The number of comorbidities reported was related to increased odds of severe outcomes and varied across countries. The odds of death for cases with zero vaccine doses were significantly higher (ORs ranging from 1.72 to 31.73) compared to cases with two doses. Similarly, the odds of death for cases with one dose were significantly higher (ORs ranging from 1.73 to 7.00) compared to cases with two doses.

CONCLUSIONS

Even in a post-vaccine implementation scenario, individual factors such as age, gender, comorbidities, and race still pose a risk to severe COVID-19, which demands tailoring public health strategies for prevention and treatment.