Cognitive dysfunction in psychiatric consultation subgroups: use of two screening tests.

Elderly patients are highly vulnerable to illness-related and drug-induced cognitive changes, especially during the acute phase of a medical or surgical illness. Using a structured cognitive screening examination enhances the accurate identification of patients with cognitive impairment. We compared the cognitive portion of the Alzheimer's Disease Assessment Scale (ADAS-COG) to the Mini-Mental State Examination (MMSE) in screening for the presence of organic brain dysfunction. Using cutoff scores, the two tests were in agreement in 94.4% of 36 cases, with total scores on the two tests correlated at r = -.90 (P less than .01). Of these 36 patients for whom psychiatric consultations were requested, 14 (38.8%) were found to be cognitively impaired. We discuss the relationship of test scores to the stated reason for the consultation, as well as variables influencing test results. Finally, we demonstrate the usefulness of cognitive testing in patients who refuse treatment.