Motor symptoms in 100 patients with delirium versus control subjects: comparison of subtyping methods.

BACKGROUND: Different motor presentations of delirium may represent clinically meaningful subtypes. OBJECTIVE: Authors sought to evaluate delirium phenomena. METHOD: They used three non-validated delirium psychomotor subtype schemas, applied to a palliative-care population. Their unique items were merged to comprise a 30-item Delirium Motor Checklist (DMC) used to collect data, rate each schema, and determine subtype frequencies in 100 consecutive DSM-IV delirium patients and 52 medically-matched control subjects without delirium. The Delirium Rating Scale-Revised-98 (DRS-R98) assessed delirium severity, and subtype categorization using its two motor items was compared with the scale that used the psychomotor schema. RESULTS: In delirium, motor disturbance was present in 100% by DMC versus 92% by DRS-R98 motor items; the DMC motor items also significantly distinguished delirium from control subjects. Motor subtype classification (hyperactive, hypoactive, mixed, and none) varied among the four methods, with low concordance across all four methods and 76% concordance for pairwise comparisons. The DRS-R-98 identified the most hypoactive delirium cases. CONCLUSION: Motor disturbances are common in delirium, although whether they represent clinical subtypes is confounded by methodological issues. New motor subtyping methods are needed that are validated in other medical populations, use matched control subjects, and have higher sensitivity and specificity for pure motor features.

Phenomenology of delirium. Assessment of 100 adult cases using standardised measures.

BACKGROUND: Delirium phenomenology is understudied. AIMS: To investigate the relationship between cognitive and non-cognitive delirium symptoms and test the primacy of inattention in delirium. METHOD: People with delirium (n=100) were assessed using the Delirium Rating Scale-Revised-98 (DRS-R98) and Cognitive Test for Delirium (CTD). RESULTS: Sleep-wake cycle abnormalities and inattention were most frequent, while disorientation was the least frequent cognitive deficit. Patients with psychosis had either perceptual disturbances or delusions but not both. Neither delusions nor hallucinations were associated with cognitive impairments. Inattention was associated with severity of other cognitive disturbances but not with non-cognitive items. CTD comprehension correlated most closely with non-cognitive features of delirium. CONCLUSIONS: Delirium phenomenology is consistent with broad dysfunction of higher cortical centres, characterised in particular by inattention and sleep-wake cycle disturbance. Attention and comprehension together are the cognitive items that best account for the syndrome of delirium. Psychosis in delirium differs from that in functional psychoses.

Porphyria and dementia: a case report.

The porphyrias are a group of rare hereditary metabolic disorders where there is an excess formation and excretion of porphyrins or their precursors. Type IIA, acute intermittent porphyria (AIP), has an estimated prevalence of one to eight per 100,000 in the general population but is thought to have a higher prevalence in psychiatric patients. AIP can present with a variety of psychiatric symptoms, often misdiagnosed. Associated neuropathological changes including focal cerebral ischaemic lesions have been found. However, to our knowledge, no case of dementia and AIP has been described. We present the case of a 56 year old man with a five-year history of progressive cognitive decline, diagnosed with AIP at an advanced stage of dementia. Whether AIP contributed to the dementia or is a coincidental finding is unknown. However treatment of AIP in this case resulted in some improvement in the patient's cognitive state.