Assessing Nurses’ Knowledge Using Case Vignettes

Delirium superimposed on dementia (DSD) occurs when a person with preexisting dementia develops delirium. Though much research has been conducted on delirium alone, until recently little attention has been given to DSD. Delirium is common among hospitalized older adults and leads to poor outcomes (Cole & Primeau, 1993; Inouye, 2006; O’Keeffe & Lavan, 1997). Delirium is also known to be prevalent in persons with dementia (Voyer, Cole, McCusker, & Belzile, 2006). Delirium superimposed on dementia ranges from 22% to 89% in hospitalized and community-dwelling older adults (Fick, Agostini, & Inouye, 2002). Previous studies have found DSD may lead to increased rates of rehospitalization within 30 days (Fick & Foreman, 2000), an increased risk of admission to a nursing home compared to older adults with dementia or delirium alone, increased health care cost and increased health care utilization (Fick, Kolanowski, Waller, & Inouye, 2005), and higher mortality rates (Leslie, Zhang, Bogardus, et al., 2005; Leslie, Zhang, Holford, et al., 2005; Voyer et al., 2006). As increasing numbers of older adults are diagnosed with dementia, attention to preventable conditions like delirium will be crucial. The problem of DSD remains a neglected area of research. Despite the high incidence of delirium in the elderly population and the substantial mortality rate associated with it, it is frequently unrecognized or misdiagnosed. In several studies, delirium in approximately half of the patients went unrecognized by nurses and physicians (Inouye, Foreman, Mion, Katz, & Cooney, ABSTRACT