NATURAL-HISTORY OF HYPERPHAGIA AND OTHER EATING CHANGES IN DEMENTIA

Objective. To investigate the natural history of overeating (hyperphag ia) and its elements during the course of dementia. Design. Prospectiv e longitudinal study of overeating (hyperphagia) in dementia. Two stud ies were carried out: (1) hyperphagia and associated eating changes we re investigated as part of a larger prospective 10-year study into beh aviour changes, using carers' reports; (2) an observational study to i nvestigate hyperphagia quantitatively; this took place over the course of a year by means of direct observation of test meals in a normal en vironment. Setting. Subjects with dementia living in Oxfordshire, UK. Participants (1) 99 people with dementia, living at home with a carer, with data for more than 1 year. (2) Nine people with a diagnosis of A lzheimer's disease who were hyperphagic. Measures. (1) The Present Beh avioural Examination was used at 4-monthly intervals to assess the sub jects' behaviour and psychological functioning. (2) Food intake, macro nutrient choice and the microstructure of eating were measured using a standardized test meal. Results. (1) Severe or persistent hyperphagia was reported in 23% of the sample and carers reported a clear onset t o hyperphagia with a median duration of 16 months. (2) From direct obs ervation, each person who was hyperphagic was seen to maintain a const ant eating rate in test meals during the course of a year but meals en ded earlier as hyperphagia decreased. Conclusions. Hyperphagia is comm on in dementia, it occurs over a single restricted period, mainly duri ng the middle stages of dementia, and is not significantly related to age, sex, diagnosis, medication or activity. (C) 1998 John Wiley & Son s, Ltd.