Hospitalisation without delirium is not associated with cognitive decline in a population-based sample of older people—results from a nested, longitudinal cohort study

Abstract

Background Acute hospitalisation and delirium have individually been shown to adversely affect trajectories of cognitive decline but have not previously been considered together. This work aimed to explore the impact on cognition of hospital admission with and without delirium, compared to a control group with no hospital admissions. Methods The Delirium and Cognitive Impact in Dementia (DECIDE) study was nested within the Cognitive Function and Ageing Study II (CFAS II)–Newcastle cohort. CFAS II participants completed two baseline interviews, including the Mini-Mental State Examination (MMSE). During 2016, surviving participants from CFAS II–Newcastle were recruited to DECIDE on admission to hospital. Participants were reviewed daily to determine delirium status. During 2017, all DECIDE participants and age, sex and years of education matched controls without hospital admissions during 2016 were invited to repeat the CFAS II interview. Delirium was excluded in the control group using the Informant Assessment of Geriatric Delirium Scale (i-AGeD). Linear mixed effects modelling determined predictors of cognitive decline. Results During 2016, 82 of 205 (40%) DECIDE participants had at least one episode of delirium. At 1 year, 135 of 205 hospitalised participants completed an interview along with 100 controls. No controls experienced delirium (i-AGeD>4). Delirium was associated with a faster rate of cognitive decline compared to those without delirium (β = −2.2, P < 0.001), but number of hospital admissions was not (P = 0.447). Conclusions These results suggest that delirium during hospitalisation rather than hospitalisation per se is a risk factor for future cognitive decline, emphasising the need for dementia prevention studies that focus on delirium intervention.

The effect of all-cause hospitalization on cognitive decline in older adults: a longitudinal study using databases of the National Health Insurance Service and the memory clinics of a self-run hospital

“…Our study also showed similar results with various neuropsychiatric evaluation items such as MMSE score, CDR grade, and KIADL score. Meanwhile, Richardson et al [19] reported that hospitalization with delirium significantly accelerated cognitive decline compared with hospitalization without it, consistent with our results. However, in our study, hospitalization without delirium was also related to cognitive decline compared to the nonhospitalized group, a result which is inconsistent with Richardson et al James et al [20] argued that a higher hospitalization rate was associated with more rapid cognitive decline.…”

Delirium in COVID-19: common, distressing and linked with poor outcomes. . . can we do better?

“…Delirium, a neuropsychiatric syndrome characterised by acute change in attention, awareness and cognition [ 1 ], is often due to the coexistence of predisposing and precipitating factors including sensory impairment, frailty, acute disease, surgery and polypharmacy [ 2 , 3 ]. Delirium is independently associated with increased hospital-acquired complications, longer stay, admission to long-term care and cognitive decline [ 4 , 5 ]. Generally difficult to prevent and manage, delirium in COVID-19 poses additional challenges, including logistical and ethical issues around pathways of care, infection control, staff time and visiting.…”

Assessing healthcare outcomes among patients with dementia requiring hospitalization for COVID‐19: An observational study

“… 4 Previous studies have also shown delirium is associated with other poor outcomes, including functional and cognitive decline. 5 , 6 , 7 , 8 Thus, our findings emphasize the importance of monitoring and timely management of acute delirium among older hospitalized adults, especially patients with increased susceptibility like PWD. Additionally, the observed association between increased prior primary care use and reduced acute delirium highlights the potential of routine outpatient management to help mitigate acute cognitive problems.…”