Effects of the COVID-19 Pandemic on the Number of New Dementia Diagnoses and the Quality of Dementia Diagnostics and Treatment

Background: Care trajectories were disrupted during the COVID-19 pandemic. However, how COVID-19 influenced the number of new dementia diagnoses, and the quality of dementia work-ups, and treatment is understudied.

Objective: To investigate the change in new dementia registrations, diagnostics, and treatment in the pre-, COVID-19 and post-COVID-19 pandemic periods.

Design: A nationwide cohort study.

Setting: This population-based study used data from the Swedish Registry for Cognitive/Dementia disorders - SveDem, and other nationwide registries in Sweden.

Participants: Persons with dementia diagnosed between 2019 and 2021 were divided into three groups based on the date of diagnosis: the pre-COVID-19 period (01 January 2019 - 29 February 2020), the COVID-19 period (01 March 2020 - 31 December 2020), and the post-COVID-19 period (01 January 2021 - 31 August 2021).

Measurements: Outcomes included dementia diagnostics and treatments.

Results: The monthly average number of new dementia cases registered in SveDem was 595, 415 and 470, respectively in the pre-COVID-19, COVID-19 and post-COVID-19 period. Compared to the pre-COVID-19 period, the monthly number of registrations decreased, but provision of the basic diagnostic work-up, its individual tests, and the use of cholinesterase inhibitors, memantine and antipsychotics were not significantly different in the COVID-19 period. Compared to the pre-COVID-19 period, new dementia diagnoses continued to be low in the post-COVID-19 period, but diagnosed individuals were more likely to receive the complete basic diagnostic work-up (OR 1.14, 95% CI 1.00 - 1.29), blood analysis (OR 1.88, 95% CI 1.44 - 2.49), computed tomography and magnetic resonance imaging (OR 1.22, 95% CI 1.01 - 1.48), occupational therapy assessment (OR 1.13, 95% CI 1.04 - 1.22), and memantine (OR 1.19, 95% CI 1.07 - 1.31).

Conclusion: The quantity of new dementia registrations in SveDem decreased in the COVID-19 period and has not returned to pre-COVID-19 levels, but the quality of the work-ups which were conducted and registered in SveDem was similar or higher than in the pre-COVID-19 period. It is imperative to implement policies to increase SveDem registration with the aim of matching or exceeding pre-COVID-19 levels.