Delirium due to avoidable hospitalizations among older adults

Abstract

AbstractBackgroundDelirium is a common complication during the course of acute care hospitalizations in older adults, particularly those with pre‐existing dementia. A substantial percentage of these admissions are for ambulatory care sensitive conditions (ACSCs) or avoidable hospitalizations – conditions that might be treated early in the outpatient setting to prevent hospitalization and its complications. We sought to examine the incidence of delirium among older adults hospitalized for ACSCs.MethodsWe examined admissions for 37,346 older adults 65 years of age admitted from January 1, 2015 to December 31, 2019 to the general inpatient (non‐ICU) units of a large regional Southeastern academic medical center. The primary outcome was delirium defined as a score 2 on the Nursing Delirium Screening Scale (NuDESC) during hospital admission. Generalized linear mixed models were used to compare rates of delirium between hospitalizations with a primary admission diagnosis for an ACSC, using standardized definitions, versus hospitalization for other non‐ACSC diagnoses, adjusting for covariates and repeated observations for individuals with multiple admissions.ResultsDelirium occurred in 30.1% of admissions for older adults. Rates were lower for those admitted for ACSCs versus those admitted for other conditions. Older age, higher number of comorbidities, presence of dementia, lower baseline cognitive scores, and lower baseline functional scores were all associated with increased risk of delirium. After adjustment for covariates, risk of delirium was 51% lower for admissions for ACSCs versus admissions for other conditions (odds ratio [OR] = 0.49; 95% CI 0.43, 0.57).ConclusionsRates of delirium among older adults hospitalized for ACSCs were lower than rates of delirium during hospitalization for other conditions, but were still substantial. This indicates that treatment of ACSCs in the outpatient setting could be an important component of efforts to reduce delirium.