Associations between COVID-19 and 30-day thromboembolic events and mortality in people with dementia receiving antipsychotic medications

Background: Antipsychotic medications are frequently prescribed to people with dementia to manage behavioural and psychological symptoms. Using a global federated research network, the objectives were to determine: 1) if COVID-19 is associated with 30-day thromboembolic events and mortality for people with dementia receiving antipsychotic medications; and 2) if the proportion of people with dementia receiving antipsychotics is higher during the COVID-19 pandemic compared to 2019.

Methods: A retrospective cohort study was conducted using TriNetX, a global federated health research network. The network was searched for people aged ≥ 65 years with dementia, COVID-19 and use of antipsychotics in the 30-days prior to COVID-19 recorded in electronic medical records between 20/01/2020 and 05/12/2020. These individuals were compared to historical controls from 2019 with dementia and use of antipsychotics in the 30-days before a visit to a participating healthcare organisation. Propensity score matching for age, sex, race, co-morbidities and use of antidepressants and anticonvulsants was used to balance cohorts with and without COVID-19.

Results: Within the TriNetX network, 8414 individuals with COVID-19, dementia and use of antipsychotics and 31,963 historical controls were identified. After propensity score matching there were 8396 individuals with COVID-19 and 8396 historical controls. The cohorts were well balanced for age, sex, race, co-morbidities and use of antidepressants and anticonvulsants. The odds of 30-day thromboembolic events and all-cause mortality were significantly higher in adults with COVID-19 (Odds Ratios: 1.36 (95% confidence interval (CI): 1.21-1.52) and 1.93 (1.71-2.17), respectively). The number of people with dementia with a visit to a participating healthcare organisation was lower between 20/01/2020 and 05/12/2020 (n = 165,447) compared to the same period in 2019 (n = 217,391), but the proportion receiving antipsychotics increased from 14.7% (95%CI: 14.6-14.9%) to 16.4% (95%CI: 16.2-16.5%), P < .0001.

Conclusions: These findings add to the evidence base that during the COVID-19 pandemic there was an increase in the proportion of people with dementia receiving antipsychotics. The negative effects of antipsychotics in patients with dementia may be compounded by concomitant COVID-19.