Protocol for the Delirium and Cognitive Impact in Dementia (DECIDE) study: A nested prospective longitudinal cohort study

Abstract

BackgroundDelirium is common, affecting at least 20% of older hospital inpatients. It is widely accepted that delirium is associated with dementia but the degree of causation within this relationship is unclear. Previous studies have been limited by incomplete ascertainment of baseline cognition or a lack of prospective delirium assessments. There is an urgent need for an improved understanding of the relationship between delirium and dementia given that delirium prevention may plausibly impact upon dementia prevention. A well-designed, observational study could also answer fundamental questions of major importance to patients and their families regarding outcomes after delirium.The Delirium and Cognitive Impact in Dementia (DECIDE) study aims to explore the association between delirium and cognitive function over time in older participants. In an existing population based cohort aged 65 years and older, the effect on cognition of an episode of delirium will be measured, independent of baseline cognition and illness severity. The predictive value of clinical parameters including delirium severity, baseline cognition and delirium subtype on cognitive outcomes following an episode of delirium will also be explored.MethodsOver a 12 month period, surviving participants from the Cognitive Function and Ageing Study II-Newcastle will be screened for delirium on admission to hospital. At the point of presentation, baseline characteristics along with a number of disease relevant clinical parameters will be recorded. The progression/resolution of delirium will be monitored. In those with and without delirium, cognitive decline and dementia will be assessed at one year follow-up. We will evaluate the effect of delirium on cognitive function over time along with the predictive value of clinical parameters.DiscussionThis study will be the first to prospectively elucidate the size of the effect of delirium upon cognitive decline and incident dementia. The results will be used to inform future dementia prevention trials that focus on delirium intervention.

Identifying delirium in Parkinson disease: A pilot study

“…Strengths of this pilot study include the prospective identification of point prevalent delirium and incident delirium using standardised procedures. 2,13 The inclusion of a collateral history was used to distinguish between participants' baseline and acute changes associated with delirium. Limitations include the small sample size at a single site, which limits the generalisability of results.…”

“…8 Prevalence of delirium was assessed prospectively using a standardised procedure using Diagnostic and Statistical Manual of Mental Disorders fifth edition (DSM-5) criteria 1 on the basis of the DECIDE study protocol. 2 Prevalence was defined as the number of cases of delirium identified at the single research visit after participants were admitted to hospital during the 4-month recruitment period. A collateral history was taken from participants' relative or carer to determine whether symptoms were an acute change or due to PD or cognitive impairment associated with PD.…”

“…Delirium is a serious acute neuropsychiatric syndrome that is common in older adults admitted to hospital and is characterised by altered levels of consciousness, confusion, and impaired attention . In older adults, delirium has been associated with poorer outcomes, such as dementia, mortality, and institutionalisation . A recent systematic review suggested that people with Parkinson disease (PD) may be at increased risk of delirium .…”

Evaluation of delirium in aged patients assisted at emergency hospital service

“…Its prevalence in hospitalized patients increases with age and varies according to the diagnosis of hospitalization (5) . This is considered the second most prevalent psychiatric syndrome in the hospital environment, after mood disorders, affecting from 29% to 64% of hospitalized patients, may occur in people of any age if the neurological impairment is extensive, and may affect up to 80% of patients admitted to intensive care units (6) .…”

The Delirium and Population Health Informatics Cohort study protocol: ascertaining the determinants and outcomes from delirium in a whole population

“…With respect to other cohort studies, DELPHIC is closely related to CFAS-DECIDE, where the delirium ascertainment protocols were developed in conjunction. [41] The community assessments have overlap with measures undertaken in the MRC National Survey for Health and Development. [42, 43] In ascertaining both delirium and dementia, DELPHIC will be a contributing cohort to the Dementias Platform UK.…”