Cardiovascular and Multisystem Outcomes Identified at Short- and Long-Term Follow-Up After COVID-19 Hospitalization: A Retrospective Cohort Study

Background: Persistent cardiovascular and multisystem manifestations remain an important concern following hospitalization for coronavirus disease 2019 (COVID-19). However, the spectrum of newly identified conditions during follow-up and their relationship with acute disease severity remain incompletely characterized. This study aimed to describe cardiovascular and multisystem diagnoses, identified during short-term and long-term follow-up and to evaluate the association between acute-phase clinical characteristics, biomarkers, and subsequent outcomes. Methods: We conducted a retrospective observational cohort study including 762 adults hospitalized with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection between January 2021 and December 2022. Follow-up data were obtained from patients who re-presented to the same hospital during short-term follow-up (mean 4.33 months; n = 130) or long-term follow-up (mean 2.06 years; n = 186). Newly documented cardiovascular and non-cardiovascular diagnoses recorded during routine clinical care were analyzed separately for each follow-up cohort. Multivariable logistic regression was used to identify predictors of in-hospital mortality and cardiovascular outcomes. Results: At least one newly documented diagnosis was identified in 120/130 patients (92.3%) during short-term follow-up and in 175/186 patients (94.1%) during long-term follow-up. Cardiovascular diagnoses were identified in 32.3% and 45.2% of patients attending short-term and long-term follow-up, respectively. Hypertension and atherosclerosis were the most frequent cardiovascular diagnoses during short-term follow-up, whereas heart failure and ischemic heart disease predominated among patients attending long-term follow-up. Pulmonary fibrosis was the most common non-cardiovascular diagnosis at both follow-up periods. Elevated D-dimer and fibrinogen levels during acute COVID-19 were independently associated with in-hospital mortality, whereas acute-phase NT-proBNP was not independently associated with cardiovascular diagnoses identified during follow-up. Conclusions: Patients who re-presented for clinical evaluation after hospitalization for COVID-19 exhibited a substantial burden of newly documented cardiovascular and multisystem diagnoses. Given the retrospective design, independent follow-up cohorts, and absence of a non-COVID control group, these findings should be interpreted as observational post-hospitalization data rather than evidence of causal or progressive post-COVID-19 disease. Prospective controlled longitudinal studies are needed to better define the long-term health consequences of SARS-CoV-2 infection.