Long-term mortality predictors in post-ICU COVID-19 survivors: the role of myocardial injury and cardiovascular comorbidities

Background The COVID-19 pandemic highlighted the critical need to understand factors influencing long-term outcomes in survivors. This study aims to identify predictors of long-term mortality in patients who survived ICU admission due to COVID-19, focusing on myocardial injury and cardiovascular comorbidities. Methods A retrospective cohort study was conducted involving 863 patients who were admitted to the ICU for COVID-19 and subsequently survived to discharge. We assessed myocardial injury, defined as an elevation of high-sensitivity troponin above the 99th percentile, and comorbidities including hypertension, prior cardiac diseases, obesity, asthma, dementia, and chronic obstructive pulmonary disease (COPD), and their association with post-discharge mortality. Cox proportional hazards regression models were used to evaluate these predictors. Results The median follow-up period was 4.1 years (IQR 3.8-4.6 years), and the median age of the cohort was 57 years (IQR 45-68.8), with 37.5% being female and 34.6% experienced myocardial injury during their ICU stay. There were 60 deaths (6.95%) during the follow-up period. In the multivariable Cox regression analysis, age (Hazard Ratio [HR] 1.06, 95% Confidence Interval [CI] 1.04-1.08), dementia (HR 3.52, CI 1.38-9.02), and COPD (HR 4.17, CI 2.00-8.74) were significantly associated with increased long-term mortality. Conversely, myocardial injury and classical cardiovascular risk factors did not significantly impact long-term mortality. Conclusions While myocardial injury and traditional cardiovascular risk factors are crucial in acute COVID-19 prognosis, they do not appear to influence long-term mortality in ICU survivors over a four-year follow-up. Age, dementia, and COPD emerged as more significant predictors of long-term outcomes. These findings could inform post-discharge patient management and highlight the need for targeted interventions addressing dementia and COPD in prolonged COVID-19 recovery.