Background: Since most studies concerning the frequency of non-cognitive symptoms of dementia are based on samples of psychiatric services, the results of these studies may be influenced by their selection procedure. For this reason, we investigated the frequency of non-cognitive dementia symptoms based on an epidemiological nursing home study.
Methods: The sample consisted of 249 nursing home residents in Austria who were interviewed with the Clinical Interview Schedule within 2 weeks after admission (T1) and again 6 months later (T2). For the analyses of the non-cognitive symptoms among the demented, only manifest clinical abnormalities observed during the interview were included. Further, mobility and impaired self-care were assessed.
Results: At admission, dementia was found in 63.9% of the sample. At T1, 38%, and at T2, 36.1% of the demented suffered from any non-cognitive symptoms. Flattened or incongruous affect, suspiciousness or aggressiveness, and anxiety were found most frequently. Multiple regression analyses showed that non-cognitive symptoms increase the risk for impaired self-care.
Discussion: Despite the fact that the frequency of several non-cognitive symptoms found in our survey is lower than reported from studies based on psychiatric samples, a high proportion of the demented in nursing homes suffer from such symptoms. Non-cognitive symptoms of dementia increase the risk for an impaired self-care, which supports the assumption that they raise the costs of caring.