A comparison of sleep profiles in patients with dementia with Lewy bodies and Alzheimer's disease

Introduction. Sleep disturbances are common in healthy old age and in demen tia syndromes. Polysomnography has demonstrated typical changes in both Alz heimer's disease (AD) and dementia with Lewy bodies (DLB) with AD being cha racterised by sundowning and sleep apnoea and DLB patients showing more dis turbances of movement control during sleep. The technical difficulties asso ciated with EEG sleep recordings mean that polysomnography is not possible out of specialist centres. Objectives. To use questionnaires to assess the frequency of sleep disturba nces in patients with Alzheimer's disease and dementia with Lewy bodies., Method. The sleep profiles of twenty patients with AD and 17 with DLB were assessed using three questionnaires, one designed to assess night time slee p disturbance, one day time sleepiness and the last carer burden. The sleep questionnaires were repeated in a subgroup after treatment with a cholines terase inhibitor (rivastigmine). Results. Level of sleep disturbance in both groups was high. DLB patients h ad more overall sleep disturbance, more movement disorders whilst asleep an d more abnormal day time sleepiness. Treatment with rivastigmine produced a trend towards normalisation of sleep profile in a small number of subjects . Conclusions. Both groups have extensive sleep problems. The DLB and AD grou ps have different sleep profiles that are of diagnostic importance and may suggest different treatment strategies. The results are consistent with tho se found from polysomnographic assessment and suggest that the questionnair es used are sensitive to detect differences previously documented with poly somnography.