How accurate are informant tools when used to diagnose dementia in hospitalised older people with delirium?

Dementia test

A recently published study has investigated the diagnostic test accuracy of two informant tools when used to diagnose dementia in patients with delirium.

It is common for older hospital patients to have both dementia and delirium; the latter is often undiagnosed as the delirium interferes with the use of cognitive testing for diagnosing dementia.

The study cites the need for new tests given the confounding effect of delirium.
The tools tested were the IQCODE-SF and the AD8 (when used for diagnosing DSM-IV dementia).

As part of the study, on admission to hospital, people aged over 70 were assessed for the presence of dementia using the short form of the Informant Questionnaire of Cognitive Decline in the Elderly (IQCODE-SF) and Alzheimer’s Disease 8 (AD8).

The conclusions drawn from the results were that the IQCODE-SF and AD8 are sensitive and specific tools, able to detect prior dementia in older people with delirium. The authors suggest that the routine use of either tool in practice could improve the recognition and subsequent management of those with dementia.
Jackson, T. A., MacLullich, A. M. J., Gladman, J. R. F., Lord, J. M., and Sheehan, B. (2016) ‘Diagnostic test accuracy of informant-based tools to diagnose dementia in older hospital patients with delirium: a prospective cohort study’, Age and Ageing, pp. 45: 505-511.