Supplementary Material for: How the COVID-19 Pandemic Impacted Neurological Hospital Admissions in Germany - A Retrospective Analysis

The COVID-19 pandemic has had a major impact on health care. Shifts in inpatient and outpatient case numbers and morbidity have been quantified in other medical specialties (e.g., oncology and psychiatry). Such an analysis is lacking in neurological cases.
Thus, we performed an anonymized, retrospective, multicenter analysis of administrative data from a network of 86 hospitals in Germany. Over 350,000 neurological cases admitted between January 2019 and December 2022 were included. The main outcome measures were: 1) deficit in inpatient hospital admissions during the pandemic compared to changes in outpatient cases; 2) morbidity, mortality, and complication rates during the pandemic; and 3) length of stay for inpatients.
There was an evident deficit in inpatient admissions between -11% and -20%, which was not compensated for by outpatient cases. Furthermore, hospitalized patients exhibited several significantly increased measures of mortality (3.7% vs. 3.2%, p < 0.001) and morbidity compared to the pre-pandemic period. Interestingly, the proportion of patients with specific chronic comorbidities at risk for severe COVID-19, such as congestive heart failure, was lower during the pandemic (10% vs. 12%, p < 0.001). Finally, the length of hospital stay was shorter during the pandemic (i.e., 6.5 vs. 6.4 days during wildtype period, p < 0.001).
These findings suggest a significant shift in hospital utilization patterns among neurology departments during the COVID-19 pandemic. While overall admissions decreased, average case severity was significantly higher. The latter was due to a selection bias because elective cases, less urgent and less morbid patients avoided hospital admission, or because their admission may have been delayed. A shorter length of stay was indicative of more efficient treatment. The avoidance of hospital care by patients with severe comorbidities could indicate a changed prioritization and utilization pattern but could also point to unmet health care needs. These observations underline the necessity for healthcare systems to adapt resource allocation and patient management strategies to ensure continuous quality of care during a pandemic.