COVID-19 more severe than bacterial, viral pneumonia in ICU-admitted older adults

Mortality rates among ICU patients aged 70 years and older were considerably higher in those with COVID-19 compared with those who had bacterial or other viral pneumonia, according to researchers.

Lenneke E. M. Haas, MD, PhD, from the department of intensive care at Diakonessenhuis, Utrecht Hospital in the Netherlands, and colleagues wrote that advanced age poses a significant risk factor for severe COVID-19 and adverse health outcomes; however, “literature about outcomes of older patients admitted to the ICU because of other pneumonia and the relation of their outcome with several factors is scare.”

“Other host factors in addition to age, like gender, comorbid conditions and severity of illness are important for outcome,” they wrote in the Journal of American Geriatrics Society. “Additionally, during this pandemic, large numbers of patients have been admitted to the ICU simultaneously and the resulting high ICU occupancy rates might have led to decreased quality of ICU care and contributed to higher mortality rates.”

In their study, the researchers analyzed data from 11,740 older adults (median age, 74 years) enrolled in the Dutch National Intensive Care Evaluation registry. The participants had been admitted to Dutch ICUs with COVID-19 (n = 5,094), bacterial pneumonia (n = 5,334) or other viral pneumonia (n = 1,312) from March 1, 2020, to Jan. 1, 2022.

Comorbidities like renal disease, respiratory and cardiovascular insufficiency “were significantly less frequent in the patients with COVID-19 compared to the patients admitted because of the other pneumonia, with even more than half of the patients admitted with COVID-19 without any known comorbidity,” Lenneke and colleagues wrote.

They found that patients with COVID-19 were more often admitted from the general ward and less often from the ED compared with patients with other pneumonia and were more likely to undergo mechanical ventilation (60.9%) and receive vasoactive drugs (53.5%).

Patients with COVID-19 had an ICU-mortality rate of 39.7%, which was significantly higher than the rate of those with bacterial pneumonia (19.1%) or other viral pneumonia (22.7%) who were admitted around the same time. Similarly, patients with COVID-19 had a significantly higher in-hospital mortality rate (47.6%) compared with those who had bacterial pneumonia (28.8%) or other viral pneumonia (31.8%).

“After adjustments for patient characteristics, including disease severity, the mortality differences became even larger,” the researchers wrote.

The differences in mortality rates were consistent with previous estimates, Lenneke and colleagues added, but they acknowledged that “comparison is complicated.”

“Obviously, mortality rates depend on several factors, and as a consequence, previous studies report a very wide range of mortality rates for older ICU patients with COVID-19,” they wrote.

The researchers concluded that “data about long-term outcome, functional outcome and [quality of life] of these patients would have large added value and therefore future studies should focus on these outcomes.”