External validation of risk scores to predict in-hospital mortality in patients hospitalized due to coronavirus disease 2019. (preprint)

Background: The coronavirus disease 2019 (COVID-19) presents an urgent threat to global health. Prediction models that accurately estimate mortality risk in hospitalized patients could assist medical staff in treatment and allocating limited resources. Aims: To externally validate two promising previously published risk scores that predict in-hospital mortality among hospitalized COVID-19 patients. Methods: Two cohorts were available; a cohort of 1028 patients admitted to one of nine hospitals in Lombardy, Italy (the Lombardy cohort) and a cohort of 432 patients admitted to a hospital in Leiden, the Netherlands (the Leiden cohort). The primary endpoint was in-hospital mortality. All patients were adult and tested COVID-19 PCR-positive. Model discrimination and calibration were assessed. Results: The C-statistic of the 4C mortality score was good in the Lombardy cohort (0.85, 95CI: 0.82-0.89) and in the Leiden cohort (0.87, 95CI: 0.80-0.94). Model calibration was acceptable in the Lombardy cohort but poor in the Leiden cohort due to the model systematically overpredicting the mortality risk for all patients. The C-statistic of the CURB-65 score was good in the Lombardy cohort (0.80, 95CI: 0.75-0.85) and in the Leiden cohort (0.82, 95CI: 0.76-0.88). The mortality rate in the CURB-65 development cohort was much lower than the mortality rate in the Lombardy cohort. A similar but less pronounced trend was found for patients in the Leiden cohort. Conclusion: Although performances did not differ greatly, the 4C mortality score showed the best performance. However, because of quickly changing circumstances, model recalibration may be necessary before using the 4C mortality score.

Clinical Characteristics and Risk Factors for Myocardial Injury and Arrhythmia in COVID-19 patients (preprint)

Background: Patients with COVID-19 can develop myocardial injury and arrhythmia during the course of their illness. However, the underlying risk factors for the development of cardiovascular related manifestations are unclear. Methods: Using a register-based multi-center cross-sectional design, we analyzed 80 patients with myocardial injury and 401 controls, as well as 71 patients with arrhythmia and 409 controls, all admitted with COVID-19. Putative risk factors for myocardial injury and arrhythmia were evaluated with logistic regression with adjustment for potential confounders. Results: COVID-19 patients with myocardial injury had fatigue (66.2%) and dyspnea (63.7%), while those with arrhythmia had dyspnea (71.8%). Patients with myocardial injury and arrhythmia had a significant mortality of 92.5% and 94.4%, respectively. A history of chronic obstructive pulmonary disease (COPD) or heart diseases was associated with an increased risk of myocardial injury (odds ratio [OR] = 1.94, 95% confidence interval [CI]: 1.01-3.71; OR = 7.43, 95% CI: 3.99-13.83) and arrhythmia (OR = 1.94, 95% CI: 1.00-3.75; OR = 13.16, 95% CI: 6.75-25.68). In addition, we found that gamma glutamyltranspeptidase (GGT) >50U/L (OR = 2.14, 95% CI: 1.37-3.32; OR = 1.85, 95% CI: 1.19-2.85), serum creatinine >111mol/L (OR = 8.96, 95% CI: 4.4-18.23; OR = 3.71, 95% CI: 2.01-6.85), serum sodium <136 mmol/L (OR = 4.68, 95% CI: 2.46-8.91; OR = 2.06; 95% CI: 1.06-4.00) were all associated with increased risk of myocardial injury and arrhythmia, respectively. Conclusion: Our reported clinical characteristics and identified risk factors are important for clinical study of COVID-19 patients developing myocardial injury and arrhythmia.

Forecast of COVID-19 related deaths in the USA (preprint)

ObjectiveDifferent governments have adopted different containment strategies for SARS-CoV-2. We compared reports of COVID-19 related deaths between countries with different strategies.DesignPublicly available data on numbers of reported COVID-19 related deaths between January 1st and April 2nd 2020 were compared between countries.ResultsIn countries that implemented strict containment strategies as soon as the virus was firmly established (e.g., Italy and Spain) the epidemic developed similarly to the development in China. Extrapolation suggests the cumulative number of deaths in Italy and Spain to rise to about 22,000 and 41,000, respectively. In South Korea where containment strategies were implemented before the virus arrived, the epidemic developed much slower. In the United States, however, where measures were taken later, the epidemic is developing explosively. Cumulative numbers of deaths in the New York, New Jersey, and Michigan area are forecast to reach about 15,000. Of note, 85% of these deaths are likely to occur within the first 50 days of the epidemic (i.e. before the end of April 2020).ConclusionsAlthough the future development of the epidemic remains difficult to predict accurately, current data suggest the United States will experience an explosive increase in deaths due to COVID-19 before the end of April 2020. Drastic measures are needed immediately to prevent other parts of the country from experiencing a development of this epidemic which is as dramatic as that seen in New York, New Jersey and Michigan.