Epidemiology of patients with dizziness over a 3-year period, requiring utilization of the emergency medical serviced system: A pre- and post-COVID pandemic comparative study using the population-based ORION registry.

Objective: We aimed to identify the proportion of each medical condition or disease contributing to dizziness and their disposition in the Emergency Department (ED).

Methods: This retrospective, descriptive study examined data from the Osaka Emergency Information Research Intelligent Operation Network system in Japan for the period from January 1, 2018 to December 31, 2020. The inclusion criteria were patients with presumptive ICD-10 codes including "dizziness" or "vertigo". Patient demographics were compared using the χ2 test and Kruskal-Wallis test. Logistic regression analysis was performed to calculate disposition from ED (emergency admission or discharge) over the 3-year study period. The adjusted odds ratio (OR) and 95% confidence interval (CI) were calculated using multivariate analyses.

Results: During the 3-year study period, a total of 1,346,457 patients (462,773 in 2018, 468,697 in 2019, and 414,987 in 2020; P < 0.001), including 53,190 patients with dizziness (18,396 in 2018, 18,649 in 2019, and 16,145 in 2020; P = 0.058), were identified as having been transported to hospitals by ambulance in Osaka Prefecture. Dizziness and giddiness (R42) was the most common form of dizziness, in 27,075 cases (9,570 in 2018, 9,613 in 2019, and 7,892 in 2020; P < 0.001; Gender composition showed 10,483 males and 16,592 females.) Vestibular Neuronitis (H81.2) showed significant increase in 2020 compared to the two preceding years (91 in 2018, 119 in 2019, and 130 in 2020, P = 0.003; including 174 males and 167 females, respectively). Of the 53,190 patients with dizziness, 11,862 (22.3%; 4,323 males, 7,539 females) were admitted to hospital. The odds ratio (OR) for emergency admission for dizziness in 2020 during the COVID-19 pandemic was 0.98 (95% confidence interval (CI), 0.93- 1.03) with reference to 2018.

Conclusion: Patients with dizziness accounted approximately 4% of ED transportations, with about 20% requiring hospital admission, irrespective of the COVID-19 pandemic. Vestibular neuronitis was significantly increased in 2020.