Single photon emission computerised tomography (SPECT) was used to measure regional brain uptake of technetium-99m hexamethylpropyleneamine oxine (Tc99m-HMPAO) in elderly patients with Alzheimer's disease (AD), multi-infarct dementia (MID) and normals (n = 20 in each group). Different patterns of uptake were found between groups when cortical uptake was normalised to cerebellar uptake. Reductions occurred in all regions in AD, being most marked in temporal and posterior parietal areas. Significant correlations were found in AD between memory impairment and decreased temporal uptake bilaterally, and between duration of illness and reduced uptake in most brain regions. MID patients showed higher uptake in the anterior parietal region than did the other groups. A variable comparing anterior to posterior uptake significantly discriminated the two patient groups.

SUMMARYDelirium in the elderly attracts sporadic attention in the literature yet constitutes a major challenge to health services, complicating many illnesses and procedures in elderly patients, associated with high rates of mortality, cutting across disciplinary boundaries and posing theoretical difficulties for the organic/ functional distinction that pervades medicine. In this review the importance of delirium in the elderly is emphasized, drawing attention to the suffering caused to the patient and the excess mortality. Problems of nomenclature (why use one word when three will do?) are discussed, the conclusion being that the oldest term is probably the best, provided that the concept of a 'syndrome' is preserved. Difficulties in research assessment are identified, and aetiology and the relationship of the delirium syndrome to dementia syndromes are discussed. Deficiencies in past approaches to management are identified and a definition of delirium is suggested. Finally, a proposal for a research programme is outlined.