Treatment intensity and mortality among COVID-19 patients with dementia: A retrospective observational study

Background We sought to determine whether dementia is associated with treatment intensity and mortality in patients hospitalized with COVID-19. Methods This study includes review of the medical records for patients >60 years of age (n = 5394) hospitalized with COVID-19 from 132 community hospitals between March and June 2020. We examined the relationships between dementia and treatment intensity (including intensive care unit [ICU] admission and mechanical ventilation [MV] and care processes that may influence them, including advance care planning [ACP] billing and do-not-resuscitate [DNR] orders) and in-hospital mortality adjusting for age, sex, race/ethnicity, comorbidity, month of hospitalization, and clustering within hospital. We further explored the effect of ACP conversations on the relationship between dementia and outcomes, both at the individual patient level (effect of having ACP) and at the hospital level (effect of being treated at a hospital with low: <10%, medium 10%-20%, or high >20% ACP rates). Results Ten percent (n = 522) of the patients had documented dementia. Dementia patients were older (>80 years: 60% vs. 27%, p < 0.0001), had a lower burden of comorbidity (3+ comorbidities: 31% vs. 38%, p = 0.003), were more likely to have ACP (28% vs. 17%, p < 0.0001) and a DNR order (52% vs. 22%, p < 0.0001), had similar rates of ICU admission (26% vs. 28%, p = 0.258), were less likely to receive MV (11% vs. 16%, p = 0.001), and more likely to die (22% vs. 14%, p < 0.0001). Differential treatment intensity among patients with dementia was concentrated in hospitals with low, dementia-biased ACP billing practices (risk-adjusted ICU use: 21% vs. 30%, odds ratio [OR] = 0.6, p = 0.016; risk-adjusted MV use: 6% vs. 16%, OR = 0.3, p < 0.001). Conclusions Dementia was associated with lower treatment intensity and higher mortality in patients hospitalized with COVID-19. Differential treatment intensity was concentrated in low ACP billing hospitals suggesting an interplay between provider bias and "preference-sensitive" care for COVID-19.