Attention, vigilance and visuospatial function in hospitalized elderly medical patients: Relationship to neurocognitive diagnosis

•More accurate and efficient identification of neurocognitive disorders requires routine formalised bedside cognitive testing•There is no consensus as to the tests that are best suited to comprise a 'cognitive vital sign'•Tests of attention, vigilance and visuospatial ability have good distinguishing ability for delirium and dementia.•Many patients with diagnosable delirium cannot engage with commonly used bedside tests of cognition•Novel approaches are needed for those with severe disturbances of arousal

ObjectiveEfficient detection of neurocognitive disorders is a key diagnostic challenge. We explored how simple bedside tests of attention, vigilance and visuospatial function might assist in identifying delirium in hospitalized patients.MethodsPerformance on a battery of bedside cognitive tests was compared in elderly medical inpatients with DSM-IV delirium, dementia, comorbid delirium-dementia, and no neurocognitive disorder.Results193 patients [mean age 79.9 ± 7.3; 97 male] were assessed with delirium (n = 45), dementia (n = 33), comorbid delirium-dementia (n = 65) and no neurocognitive disorder (NNCD) (n = 50). The ability to meaningfully engage with the tests varied from 84% (Spatial Span Forwards) to 57% (Vigilance B test), and was especially problematic among the comorbid delirium-dementia group. The NNCD was distinguished from the delirium groups for most tests, and from the dementia group for the Vigilance B test and the Clock Drawing Test. The dementia group differed from delirium groups in respect of the Months Backward Test, Vigilance A and B tests, Global assessment of visuospatial ability and the Interlocking Pentagons Test. Overall, patients with delirium were best identified by three tests - the Months Backward Test, Vigilance A test and the Global Assessment of visuospatial function with failure to correctly complete any two of these predicting delirium status in 80% of cases.ConclusionSimple bedside tests of attention, vigilance and visuospatial ability can help to distinguish neurocognitive disorders, including delirium, from other presentations. There is a need to develop more accurate methods specifically designed to assess patients with neurocognitive disorder who are unable to engage with conventional tests.