Prevalence of cognitive impairment in the hospitalized elderly.

Surveys of older populations reveal rates of senile dementia varying from 5.2% to 25%. The specialist branch of psychiatry dealing with the elderly advocates that services for these patients and their carers should predominantly be based outside hospital. The following study was conducted in Limerick, Ireland before the arrival of a consultant in old age psychiatry and associated services. Its aim was to assess the extent to which the patients with dementing disorders were using hospital facilities other than those in psychiatric wards. The study assessed 371 patients aged 65 years and over in various medical and surgical units. The Mini Mental State Examination was performed on all patients. Patients with scores of 23/31 or less were considered to have significant cognitive impairment and those with 16 or less to have severe impairment. As mental performance can be impaired by acute illness, methods were used to avoid such patients being wrongly labelled as suffering from dementia. In the acute hospital 112 patients with an average age of 74.7 years were examined and 22.3% of these had significant cognitive impairment. These patients were predominantly sited on medical wards. On acute medical wards 31% of older patients had significant impairment compared to only 7.3% on the surgical wards. In the orthopaedic unit 15.8% of the elderly had evidence of cognitive impairment. In hospitals specializing in continuing care of the elderly the proportion was 70.6% and of these 46% were severely impaired. We conclude that in the absence of specialized dementia services for the elderly, medical beds both in the acute and long-stay sector will be used for these patients more than their medical needs might otherwise require.