The Impact of the Colorado State-Wide Lockdown on Non-COVID-19 Related ICU Admissions and Mortality

Abstract

RATIONALE: The COVID-19 pandemic has rapidly become the most significant worldwide public health crisis in the modern era. Like other states around the country, the state of Colorado instituted a statewide lockdown to combat increasing case and hospitalization rates for COVID-19 throughout the state. The impact of this mandate on the ICU admission rates and outcomes of other medical problems has never been investigated. Our study aimed to determine the effects of stay-at-home orders on outcomes for other diagnoses by analyzing ICU admission rates and outcomes of patients presenting to the ICU for non-COVID related issues before, during, and after the statewide mandate. METHODS: We performed a retrospective analysis of all ICU admissions in three phases: before (2 months prior), during, and 1.5 months after the statewide lockdown (March 26 to April 27, 2020). We included all patients admitted to the University of Colorado Health System hospitals ICUs within this defined time period. A time-to-event analysis was performed with the date of index ICU stay set as time zero. Baseline characteristics were obtained. Primary outcome measures were 28-day mortality and all-time mortality. Kaplan-Meier curves were used to estimate survival probabilities, while Cox regression and multivariable logistic regression were utilized to model phase-specific mortality controlling for comorbidities, demographics, and admission diagnoses. Counts of typical ICU admission diagnoses were also analyzed to determine any changes across lockdown periods. RESULTS: 9201 total ICU admissions occurred, of which 8154 (88.6%) were non-COVID-19 related. Approximately 57.4% were male with a mean age of 60.4 years. 28-day mortality rates for non-COVID-19 ICU admissions were 475 (11.0%), 127 (13.8%), and 306 (10.5%) before, during, and after the lockdown, respectively. The increased mortality during lockdown persisted after adjustment for comorbidities and demographics (HR=1.23, 95% CI, 1.007 to 1.512, p = 0.043). Acute respiratory failure was the most common diagnosis in each time period, and increased during lockdown (p<0.001). Admissions for sepsis increased during lockdown and decreased after (p = 0.001);myocardial infarction (MI) admission decreased during lockdown but increased after (p = 0.014);and alcohol withdrawal (AW) admission increased both during and after lockdown (p < 0.001). CONCLUSIONS: For non-COVID-19 related ICU admissions, the mortality rate increased during the state-wide shutdown but decreased after shutdown, although this difference became insignificant after controlling for patient admission diagnoses. Admission diagnoses also differed with more admissions for sepsis and AW during lockdown and more admissions for MI and AW after lockdown.