Severity of Disease and COVID-19 Complications During Hospital Stay: A Prospective Cohort Study

COVID-19, with its high transmission and mortality rates and unknown outcomes, has become a major concern in the world. Among people with COVID-19, severe cases can quickly progress to serious complications, and even death. So, the present study aimed to examine the relationship between the severity of the disease and the outcome in patients afflicted by COVID-19 during hospitalization.

A total of 653 patients with COVID-19 aged 18 years or older were included from Khorshid hospital in Isfahan, Iran and followed for a mean of 22.72 days (median 23.50; range 1-47). Severe COVID-19 was defined by respiration rate≥30 times/min, oxygen saturation level≤88% in the resting position, and pulse rate≥130/min. The primary outcome was mortality. The secondary outcomes included need for mechanical ventilation and intensive care unit (ICU) admission.

During 4233 person-days of follow-up, 49 (7.5%) deaths, 27 (4.1%) invasive ventilation and 89 (13.6%) ICU admissions in hospital were reported. After adjustment for potential confounders, severity of the disease was positively associated with risk of mortality, invasive ventilation and ICU admissions (hazard ratio [HR]: 5.99; 95% CI: 2.85, 12.59; P<0.001, HR: 7.09; 95% CI: 3.24, 15.52; P<0.001 and HR: 4.88; 95% CI: 2.98, 7.98; P<0.001, respectively). In addition, greater age (HR=1.04; 95% CI=1.02-1.07; P=0.002), chronic kidney disease (HR=3.05; 95% CI=1.35, 6.90; P=0.008), blood urea nitrogen (BUN) (HR=1.04; 95% CI=1.03-1.05; P<0.001) and creatinine (HR=1.44; 95% CI=1.26-1.65; P<0.001) were probably significant risk factors for mortality in severe COVID-19 patients.

More intensive therapy and special monitoring should be implemented for patients with older age, hypertension and kidney disease who are infected with COVID-19 to prevent rapid worsening.