Delirium in the elderly. The construction of a rating scale and aspects on risk factors and treatment

Sammanfattning: The rates of delirium were studied in patients with four different dementia disorders and also in patients with different regional brain syndromes. The function of the stress-regulating system was compared between demented patients with delirium and those without. The efficacy and side-effects of an atypical neuroleptic drug in the treatment of confusional symptoms, behavioural disturbances and psychotic symptoms in elderly, mostly demented patients were investigated in a pilot study. An instrument for the assessment of changes in symptoms of delirium over time was constructed and evaluated.Delirium occurred in 37% of the demented patients in the absence of any acute somatic disorder. Independently of age and severity ot dementia, delirium was more common in late-onset Alzheimer's disease and vascular dementia than in early-onset Alzheimer's disease and frontotemporal dementia. Delirium was also more common in demented patients with symptoms indicating global impairment of the brain than in those with symptoms indicating more limited brain disorder, independently of severity of the dementia disorder. Thus demented patients with a more global brain disorder seem to be more at risk of developing delirium than those with more localised brain dysfunction. In an investigation of the stress-regulating system in the HPA axis 75% of the demented patients with moderate to severe delirium showed pathological dexamethasone suppression test (DST) responses compared with 33% of those without delirium. Age, post-DST cortisol level and severity of dementia all independently predicted delirium. The results of the investigation indicate that disturbances in the stress-regulating system. may be an important risk factor for delirium.A retrospective pilot study of the efficacy and side-effects of an atypical neuroleptic drug showed that patients with predominant psychomotor hyperactivity and psychotic symptoms benefitted most from the treatment with low doses of the drug.Confusional State Evaluation (CSE), a rating scale for measuring changes in severity of delirium, was developed. The assessment is based mainly on the patient's condition during an interview. The scale consists of 22 items. Scores on 12 of these are summarised to give a ?confusion score?. The validity and inter-rater reliability of the scale was tested and found satisfactory. The scale is useful for evalutation of the efficacy of interventions in demented and non-demented elderly people with delirium.