COVID-19 and Atrial Fibrillation: Elevated Mortality Risk Unveiled

The frequency and prognosis of newly diagnosed atrial fibrillation (AF) in patients hospitalized with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of the coronavirus disease 2019 (COVID-19) pandemic, were examined in a recent Scientific Reports article.

Background

According to recent research, 5–10% of hospitalized sepsis patients experience atrial fibrillation (AF). It’s possible that these people need to be admitted to intensive care units (ICUs). There is evidence that the development of AF increases in-hospital mortality.

According to a recent study, the prognosis for COVID-19 worse in those with recently diagnosed AF.

A newly diagnosed AF was found to increase the death risk of individuals hospitalized with COVID-19 in two multicenter US-based investigations.

Another study, which used data from the American Heart Association COVID-19 Cardiovascular Registry, found no connection between in-hospital mortality and newly diagnosed AF, which contradicted the previous finding.

It is unclear whether the previous research distinguished between pre-existing and newly diagnosed AF when analyzing the effect of AF on hospitalized COVID-19 patients.

This misclassification would have a major impact on the study’s findings on the association between newly diagnosed AF and unfavorable COVID-19 outcomes.

About the study

The current study accurately classified pre-existing and newly diagnosed AF using countrywide longitudinal data from the US Veterans Health Administration (VHA). This information includes medical information on patients who were hospitalized as a result of SARS-CoV-2 infection.

The primary goal of this study is to determine the prevalence of newly diagnosed AF in COVID-19 patients hospitalized. The relationship between newly diagnosed AF and in-hospital mortality was also investigated.

Veterans over the age of 65 who become infected with SARS-CoV-2 between June 1, 2020, and January 31, 2022 were identified using the VHA Corporate Data Warehouse.

To determine the participants’ comorbidities, this data was matched with Medicare parts A, B, and D.

This study included patients who had been hospitalized for more than 24 hours but less than a week and were regular VHA users. This method improved diagnostic specificity in distinguishing between newly diagnosed AF and pre-existing AF.

Study finding

The study group included a total of 23,299 patients. The patients’ average age was 76 years, and the bulk of the study population was male. Although the majority of participants were White, there was a small minority of American Indian, Native Hawaiian, Asian, Black, and Hispanic or Latino participants.

Approximately 7.5% of patients had just been diagnosed with AF. Around 29% of the trial participants had pre-existing AF.

Interestingly, when compared to patients with pre-existing AF, newly diagnosed AF patients were younger and healthier, and the majority of them were Black. These people had a lower risk of having both cardiovascular and non-cardiovascular comorbidities.

The majority of patients with pre-existing AF were being treated with beta-blockers, oral anticoagulants, and antiarrhythmics designed specifically for AF.

In this study, newly diagnosed AF was predicted to be 5.3%, with pre-existing AF accounting for 29.2%.

The new AF diagnosis was associated with 16.5% in-hospital mortality and 22.7% 30-day mortality. According to the current study, newly diagnosed AF raised the risk of mortality by 10% when compared to pre-existing AF.

Strengths and limitations

The current study has numerous strengths, including an investigation of VHA frequent users and a link to Medicare data. This method improved the diagnostic specificity of both new and pre-existing AF diagnoses.

The failure of the American Heart Association COVID-19 Cardiovascular Registry to discover a link between newly diagnosed AF and in-hospital mortality could be attributed to the probable misclassification of pre-existing AF as newly diagnosed AF.

This study also has several drawbacks, such as AF diagnostic bias. Because of the prolonged time of heart rhythm monitoring, there is a risk of a rise in the number of newly diagnosed AF.

Because the precise timing of AF onset could not be ascertained, the survival analysis was not performed by controlling for time-varying variables.

Despite earlier research indicating that echocardiographic parameters such as left ventricular wall thickness, left atrial size, and left ventricular ejection fraction influence AF symptoms and clinical outcomes, these features were not taken into account due to a lack of data availability.

The study cohort was limited to the US population, with the majority of participants being White, limiting the findings’ generalizability.

Conclusions

In conclusion, the current investigation found that, as compared to pre-existing AF, newly diagnosed AF in COVID-19 patients increases the risk of mortality.

More research is needed to identify whether newly diagnosed AF is a marker or contributing to poor disease outcomes in the future. To prevent the emergence of new AF during SARS-CoV-2 infection, new methods must be devised.

For more information: Ko, D. et al. (2024) Incidence and prognostic significance of newly-diagnosed atrial fibrillation among older U.S. Veterans hospitalized with COVID-19. Scientific Reports. 14(1), pp.1-7. doi:https://doi.org/10.1038/s41598-024-51177-6.