As coronavirus disease 2019 continues to sweep the nation, hundreds of questions still surround the virus that causes this disease. Many of those unanswered questions revolve around the risk of contracting the disease—especially in places where the statistics run rampant and patients desperately need access to the intensive care unit.

Many patients who have contracted COVID-19 are critically ill required care in the intensive care unit. But evaluating the independent risk factors associated with the mortality of patients is tricky. In order to do so, a group of researchers studied data in Lombardy, Italy, in order to answer the question—what are the risk factors associated with mortality among critically ill patients with lab-confirmed coronavirus disease 2019 admitted to ICU units in Italy?

Understanding the Study: The Methodology and Findings

This study was a retrospective, observational cohort study that included 3,988 consecutively critically ill patients who had laboratory-confirmed COVID-10 and were referred to ICU admission to the coordinating center of the COVID-19 Lombardy ICU Network. The confirmation of severe acute respiratory syndrome was done by real-time reverse transcriptase-polymerase chain reaction assay of nasopharyngeal swabs.

This study looked at the time period from February 220 to April 22, 2020. The follow-up of this study was completed on May 30, 2020.

The main measurement of this study was supposed to look at the time to death from ICU admission to hospital discharge, and the independent risk factors were evaluated with a multivariable Cox proportional hazards regression.

So, what exactly happened?

Of the nearly 4,000 patients (3,988 to be exact) included in the cohort study had a median age of 63, of the group of patients, 3,188 were men, and 1,988 of 3,300 had at least 1 comorbidity. In the subgroup of the first 1,715 patients, 865 had been discharged from the intensive care unit, 836 had died in the ICU, and 14 were still in the intensive care unit. Overall, 915 patients died in the hospital for overall hospital mortality.

At ICU admission, 2,292 patients required invasive mechanical ventilation (IMV). The median follow-up was 44 days, median time from symptom onset to ICU admission was 10 days, the median length of ICU stay was 12 days, and the medium length of IMV was 10 days.

As a result, the study confirmed at least one important factor. In the retrospective cohort study of critically ill patients admitted to ICUs in Lombardy, Italy, with lab-confirmed COVID-19, most patients observed required invasive medical ventilation. The mortality rate and the absolute mortality studied were high, too.