Does the Etiology, Phenomenology and Motor Subtype of Delirium Differ When It Occurs in Patients With An Underlying Dementia?: A Multi-Site, International Study.

OBJECTIVES: To compare the etiology, phenomenology and motor subtype of delirium in patients with and without an underlying dementia. METHODS: A combined dataset (n = 992) was collated from two databases of older adults (>65 years) from liaison psychiatry and palliative care populations in Ireland and India. Phenomenology and severity of delirium were analysed using the Delirium Symptom Rating Scale Revised (DRS-R98) and contributory etiologies for the delirium groups were ascertained using the Delirium Etiology Checklist (DEC). Delirium motor subtype was documented using the abbreviated version of the Delirium Motor Subtype Scale (DMSS4). RESULTS: Delirium superimposed on dementia (DSD) showed greater impairment in short term memory, long term memory and visuospatial ability than the delirium group but showed significantly less perceptual disturbance, temporal onset and fluctuation. Systemic infection, cerebrovascular and other Central nervous system etiology were associated with DSD while metabolic disturbance, organ insufficiency and intracranial neoplasm were associated with the delirium only group. CONCLUSION: The etiology and phenomenology of delirium differs when it occurs in the patient with an underlying dementia. We discuss the implications in terms of identification and management of this complex condition.

How do delirium motor subtypes differ in phenomenology and contributory aetiology? a cross-sectional, multisite study of liaison psychiatry and palliative care patients.

OBJECTIVES: To investigate whether delirium motor subtypes differ in terms of phenomenology and contributory aetiology. DESIGN: Cross-sectional study. SETTING: International study incorporating data from Ireland and India across palliative care, old age liaison psychiatry and general adult liaison psychiatry settings. PARTICIPANTS: 1757 patients diagnosed with delirium using criteria from the Diagnostic and Statistical Manual of Mental Disorders, Fourth edition (DSM IV). PRIMARY AND SECONDARY OUTCOME MEASURES: Hyperactive, mixed and hypoactive delirium subtypes were identified using the abbreviated version of the Delirium Motor Subtype Scale. Phenomenology was assessed using the Delirium Rating Scale Revised. Contributory aetiologies were assessed using the Delirium Aetiology Checklist (DEC), with a score >2 indicating that the aetiology was likely or definitely contributory. RESULTS: Hypoactive delirium was associated with dementia, cerebrovascular and systemic infection aetiologies (p<0.001) and had a lower overall burden of delirium symptoms than the other motor subtypes. Hyperactive delirium was associated with younger age, drug withdrawal and the DEC category other systemic aetiologies (p<0.001). Mixed delirium showed the greatest symptom burden and was more often associated with drug intoxication and metabolic disturbance (p<0.001). All three delirium motor subtypes had similar levels of impairment in attention and visuospatial functioning but differed significantly when compared with no subtype (p<0.001). CONCLUSIONS: This study indicates a pattern of aetiology and symptomatology of delirium motor subtypes across a large international sample that had previously been lacking. It serves to improve our understanding of this complex condition and has implications in terms of early detection and management of delirium.

Comparison of novel tools with traditional cognitive tests in detecting delirium in elderly medical patients.

BACKGROUND: Efficient detection of delirium and comorbid delirium-dementia is a key diagnostic challenge. Development of new, efficient delirium-focused methods of cognitive assessment is a key challenge for improved detection of neurocognitive disorders in everyday clinical practice. AIM: To compare the accuracy of two novel bedside tests of attention, vigilance and visuospatial function with conventional bedside cognitive tests in identifying delirium in older hospitalized patients. METHODS: 180 consecutive elderly medical inpatients (mean age 79.6 ± 7.2; 51% female) referred to a psychiatry for later life consultation-liaison service with delirium, dementia, comorbid delirium-dementia and cognitively intact controls. Participants were assessed cross-sectionally with conventional bedside cognitive tests [WORLD, Months Backward test (MBT), Spatial span, Vigilance A and B, Clock Drawing test and Interlocking Pentagons test] and two novel cognitive tests [Lighthouse test, Letter and Shape Drawing test (LSD)-4]. RESULTS: Neurocognitive diagnoses were delirium (n = 44), dementia (n = 30), comorbid delirium-dementia (n = 60) and no neurocognitive disorder (n = 46). All conventional tests had sensitivity of > 70% for delirium, with best overall accuracy for the Vigilance-B (78.3%), Vigilance-A (77.8%) and MBT (76.7%) tests. The sustained attention component of the Lighthouse test was the most distinguishing of delirium (sensitivity 84.6%; overall accuracy 75.6%). The LSD-4 had sensitivity of 74.0% and overall accuracy 74.4% for delirium identification. Combining tests allowed for enhanced sensitivity (> 90%) and overall accuracy (≥ 75%) with the highest overall accuracy for the combination of MBT-Vigilance A and the combined Vigilance A and B tests (both 78.3%). When analyses were repeated for those with dementia, there were similar findings with the MBT-Vigilance A the most accurate overall combination (80.0%). Combining the Lighthouse-SA with the LSD-4, a fail in either test had sensitivity for delirium of 91.4 with overall accuracy of 74.4%. CONCLUSION: Bedside tests of attention, vigilance and visuospatial ability can help to distinguish neurocognitive disorders, including delirium, from other presentations. The Lighthouse test and the LSD-4 are novel tests with high accuracy for detecting delirium.

Attention, vigilance, and visuospatial function in hospitalized elderly medical patients: relationship to delirium syndromal status and motor subtype profile.

ABSTRACTBackground:The early and effective detection of neurocognitive disorders poses a key diagnostic challenge. We examined performance on common cognitive bedside tests according to differing delirium syndromal status and clinical (motor) subtypes in hospitalized elderly medical inpatients. METHODS: A battery of nine bedside cognitive tests was performed on elderly medical inpatients with DSM-IV delirium, subsyndromal delirium (SSD), and no delirium (ND). Patients with delirium were compared according to clinical (motor) subtypes. RESULTS: A total of 198 patients (mean age 79.14 ± 8.26) were assessed with full syndromal delirium (FSD: n = 110), SSD (n = 45), and ND (n = 43). Delirium status was not associated with differences in terms of gender distribution, age, or overall medication use. Dementia burden increased with greater delirium status. Overall, the ability to meaningfully engage with the tests varied from 59% for the Vigilance B test to 85% for Spatial Span Forward test and was lowest in patients with FSD, where engagement ranged from 32% for the Vigilance B test to 77% for the Spatial Span Forwards test. The ND group was distinguished from SSD group for the Months of the year backwards, Vigilance B, global VSP, Clock Drawing test, and Interlocking Pentagons test. The SSD group was distinguished from the FSD group by Vigilance A, Spatial Span Forward, and Spatial Span Backwards. Regarding differences among motor subtypes in terms of percentage engagement and performance, the No subtype group had higher ratings across all tests. Delirious patients with no subtype had significantly lower scores on the DRS-R98 than for the other three subtype categories. CONCLUSIONS: Simple bedside tests of attention, vigilance, and visuospatial ability are useful in distinguishing neurocognitive disorders, including SSD from other presentations.

Development of the four-item Letter and Shape Drawing test (LSD-4): A brief bedside test of visuospatial function.

Conventional bedside tests of visuospatial function such as the Clock Drawing (CDT) and Intersecting Pentagons (IPT) lack consistency in delivery and interpretation. We compared performance on a novel test of visuospatial ability - the LSD - with the IPT, CDT and MMSE in 180 acute elderly medical inpatients [mean age 79.7±7.1 (range 62-96); 91 females (50.6%)]. 124 (69%) scored ≤23 on the MMSE; 60 with mild (score 18-23) and 64 with severe (score ≤17) impairment. 78 (43%) scored ≥6 on the CDT, while for the IPT, 87 (47%) scored ≥4. The CDT and IPT agreed on the classification of 138 patients (77%) with modest-strong agreement with the MMSE categories. Correlation between the LSD and visuospatial tests was high. A four-item version of the LSD incorporating items 1,10,12,15 had high correlation with the LSD-15 and strong association with MMSE categories. The LSD-4 provides a brief and easily interpreted bedside test of visuospatial function that has high coverage of elderly patients with neurocognitive impairment, good agreement with conventional tests of visuospatial ability and favourable ability to identify significant cognitive impairment. [181 words].

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

OBJECTIVE: Efficient 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. METHODS: Performance 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. RESULTS: 193 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. CONCLUSION: Simple 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.

Comparison of cognitive and neuropsychiatric profiles in hospitalised elderly medical patients with delirium, dementia and comorbid delirium-dementia.

OBJECTIVES: Differentiation of delirium and dementia is a key diagnostic challenge but there has been limited study of features that distinguish these conditions. We examined neuropsychiatric and neuropsychological symptoms in elderly medical inpatients to identify features that distinguish major neurocognitive disorders. SETTING: University teaching hospital in Ireland. PARTICIPANTS AND MEASURES: 176 consecutive elderly medical inpatients (mean age 80.6 ± 7.0 years (range 60-96); 85 males (48%)) referred to a psychiatry for later life consultation-liaison service with Diagnostic and Statistical Manual of Mental Disorders (DSM) IV delirium, dementia, comorbid delirium-dementia and cognitively intact controls. Participants were assessed cross-sectionally with comparison of scores (including individual items) for the Revised Delirium Rating Scale (DRS-R98), Cognitive Test for Delirium (CTD) and Neuropsychiatric Inventory (NPI-Q). RESULTS: The frequency of neurocognitive diagnoses was delirium (n=50), dementia (n=32), comorbid delirium-dementia (n=62) and cognitively intact patients (n=32). Both delirium and comorbid delirium-dementia groups scored higher than the dementia group for DRS-R98 and CTD total scores, but all three neurocognitively impaired groups scored similarly in respect of total NPI-Q scores. For individual DRS-R98 items, delirium groups were distinguished from dementia groups by a range of non-cognitive symptoms, but only for impaired attention of the cognitive items. For the CTD, attention (p=0.002) and vigilance (p=0.01) distinguished between delirium and dementia. No individual CTD item distinguished between comorbid delirium-dementia and delirium. For the NPI-Q, there were no differences between the three neurocognitively impaired groups for any individual item severity. CONCLUSIONS: The neurocognitive profile of delirium is similar with or without comorbid dementia and differs from dementia without delirium. Simple tests of attention and vigilance can help to distinguish between delirium and other presentations. The NPI-Q does not readily distinguish between neuropsychiatric disturbances in delirium versus dementia. Cases of suspected behavioural and psychological symptoms of dementia should be carefully assessed for possible delirium.