Effects of COVID-19 on Hospital Utilization Trends

With the onset of COVID-19, hospitals statewide saw a sharp drop in inpatient discharges, emergency department utilization, and ambulatory surgeries.

After January 2020, hospitals throughout California began to see utilization drop sharply across all three settings. The downward trend continued until April 2020, after which utilization began to rise again. This drop is reflected when focusing on patients with common health conditions, such as diabetes, hypertension, and asthma. However, the utilization for people who experience homelessness did not show similar downward trends in utilization compared to other groups.

HCAI’s visualizations are derived from patient administrative data from hospital billing systems and is not disease surveillance data. At the time of publishing, hospital data for 2020 is the most current and validated data available to HCAI.  For the latest COVID-19 data from the state’s disease surveillance systems, please visit https://covid19.ca.gov.

Key Findings

  • Individuals with asthma, cancer, chronic obstructive pulmonary disease (COPD), diabetes, hypertension, obesity, sepsis, and stroke all reflected a sharp decline in utilization across settings after January 2020 through April 2020. Utilization of the emergency department remained low in late 2020 relative to previous years. Inpatient discharges and ambulatory surgeries rebounded almost to levels typically seen pre-pandemic. 
  • The trendlines for patients who experience homelessness do not reflect the same change, aside from a decline in ambulatory surgeries in early 2020. Trendlines for homeless patients may not reflect actuality due to variations in reporting over time. The homeless population is undercounted in 2018 due to the inability to designate homeless persons by ZIP code that year. 
  • As COVID-19 patient deaths rose in 2020, in-hospital deaths among inpatient discharges and the emergency department trended higher in late 2020 than in previous years. The increase is reflected across patients in all health categories.
  • Patients experiencing obesity and pneumonia demonstrated a greater likelihood of COVID-19 as a primary diagnosis when looking at in-hospital deaths. In the emergency department, the same was true of patients experiencing pneumonia and cardiac arrest.

The visualization below focuses on statewide utilization trends in inpatient discharges, emergency department treat and release utilization, and ambulatory surgeries beginning in 2018. The sharp downward trend in all three settings begins after January 2020 with the introduction of COVID-19 and hits a low point in April 2020 before beginning to rise again. Utilization of the emergency department remained low in late 2020 relative to previous years. Inpatient discharges and ambulatory surgeries rebounded nearly to levels typically seen pre-pandemic. 

This visualization displays utilization trends in the same settings as above but focuses on trends in key health-related topics. A sharp decline in utilization is seen starting after January 2020 among nearly all patients. Trends in hospital utilization of the homeless population were much less affected.

By default, this visualization displays a handful of selected health-related topics and hospital utilization trends among inpatient discharges in 2018-2020. The dropdown filters can be used to change the setting, select as many health-related topics as desired, and change the time span of focus. All trends reflect encounters and not unique patients. 

Note: The number of encounters is all recorded health care encounters for a specific health-related topic. Individual patients may be counted in more than one category if they received multiple diagnoses during a single encounter (e.g., a person who had diabetes and pneumonia would be counted in both diabetes and pneumonia categories). The COVID-19 trend lines begin with April 2020 when the COVID-19 specific diagnosis code U07.1 was added to the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM).”  

This visualization focuses on mortality trends in inpatient discharges, emergency department treat and release utilization, and ambulatory surgeries beginning in 2018. As COVID-19 patient deaths rose in 2020, in-hospital deaths among inpatient discharges and the emergency department trended higher in late 2020 than in previous years.

By default, this visualization displays a handful of selected health-related topics and in-hospital deaths among inpatient discharges in 2018-2020. The dropdown filters can be used to change the setting, select as many health-related topics as desired, and change the time span of focus.

Note: The number of deaths is all recorded in-hospital deaths for a specific health-related topic. Individual patients may be counted in more than one category if they received multiple diagnoses during the encounter in which the death occurred (e.g., a person who had diabetes and pneumonia would be counted in both diabetes and pneumonia categories). The COVID-19 trend lines begin with April 2020 when the COVID-19 specific code U07.1 was added to ICD-10-CM.

This visualization focuses on mortality trends and diagnosis breakdown in inpatient discharges, emergency department treat and release utilization, and ambulatory surgeries in 2020. Patients experiencing cardiac arrest, pneumonia, and obesity demonstrated a greater likelihood of COVID-19 as a primary diagnosis. COVID-19 was more often present as a primary diagnosis in deaths among inpatient discharges than in emergency department deaths.

The diagnosis legend is meant to demonstrate a breakdown of how each diagnosis was assigned. For example, among in-hospital deaths including a cancer diagnosis, the breakdown includes a count of cancer as primary diagnosis, cancer as a secondary diagnosis with COVID-19 as the primary diagnosis, and cancer as a secondary diagnosis with any primary diagnosis unrelated to COVID-19.

Note: The number of deaths is all recorded in-hospital deaths for a specific health-related topic. Individual patients may be counted in more than one category if they received multiple diagnoses during the encounter in which the death occurred (e.g., a person who had diabetes and pneumonia would be counted in both diabetes and pneumonia categories). The COVID-19 trend lines begin with April 2020 when the COVID-19 specific code U07.1 was added to ICD-10-CM.

This visualization focuses on mortality trends and secondary diagnosis breakdown in inpatient discharges, emergency department treat and release utilization, and ambulatory surgeries in 2020. Among in-hospital deaths, patients with obesity and pneumonia demonstrated greater likelihood of having COVID-19 as a primary diagnosis compared to other patients. When looking at deaths occurring in the emergency department, patients experiencing cardiac arrest and pneumonia demonstrated a higher likelihood of COVID-19 as a primary diagnosis.

Note: The number of deaths is all recorded in-hospital deaths for a specific health-related topic. Individual patients may be counted in more than one category if they received multiple diagnoses during the encounter in which the death occurred (e.g., a person who had diabetes and pneumonia would be counted in both diabetes and pneumonia categories).

Additional Information

Temporal Coverage: 2018-2020
Spatial/Geographic Coverage: Statewide
Frequency: Quarterly
Source Link: Healthcare Utilization
Citation: Department of Health Care Access and Information: Healthcare Utilization, Patient-Level Administrative Data
Other: COVID-19 Data Reporting Guidance