Delirium and dementia in acute medical admissions of elderly patients in Iceland.

A prospective study was carried out in a general hospital in Reykjavík to evaluate the prevalence of delirium and dementia among 331 patients 70 years and older who were admitted as an emergency to the medical department. Cognitive function was screened with Mental Status Questionnaire (MSQ) and Mini-Mental State Examination (MMSE) and diagnosed according to DSM-III-R for delirium and dementia. Other information obtained included social and demographic factors, drug consumption, the main condition underlying the delirium and outcome. Severe cognitive dysfunction was present in 32% of all acutely admitted patients 70 years and older, which were diagnosed further as delirium 14% and dementia 18%. At follow-up, concurrent dementia was found in 70% of the delirium patients. The main causes for delirium were cardiac failure 27%, stroke 22% and sepsis 16% and the mortality rate was 32% compared with 8% in dementia alone. The prognosis of patients with delirium and dementia depends on detecting these disorders, and the clinical skills of physicians working with acutely ill elderly patients can be improved by relatively simple screening questionnaires such as the MSQ and MMSE.

Dementia and depression in old age: psychophysiological aspects.

This study describes the psychophysiological results of a larger investigation of the clinical, morphological, psychometric and psychophysiological aspects of dementia of the Alzheimer type and depression in elderly patients. Healthy volunteers provided a further measure of control. It was found that widely used clinical rating scales delineated the 3 groups of subjects to a significant degree. The average frequency of the electroencephalogram (EEG), the P2-N2 peak-to-peak amplitude and P3 latency of the auditory evoked potential and a characteristic downward shift of the EEG power spectrum differed significantly between demented patients, depressive patients and normal controls. The higher total power in the EEG of the dementia group did not prove statistically significant, probably because of the small numbers. Other psychophysiological measures such as skin conductance level (SCL) and skin temperature (ST) did not reveal statistically significant differences between the groups. Thus, certain psychophysiological measurements may become valuable in the differential diagnosis of these disorders.

Electroencephalographic correlates of electroconvulsive therapy.

The aim of this investigation was to study the detailed profile and persistence of electroconvulsive therapy (ECT)-induced EEG correlates. Subjects were submitted to a detailed clinical evaluation as well as automated, computerized EEG recordings. Analysis was performed of different frequency bands, mean frequency and total power as well as a detailed study of cortical auditory-evoked responses. Age and sex-matched control subjects comprised a group of comparable patients, none of whom had received ECT, a second control group of healthy volunteers and a third group of amitriptyline-treated patients. No statistically significant EEG changes were found among patients who had been treated with ECT from several months to several years prior to the investigation. During ECT, highly significant cumulative effects were observed in most of the EEG measures, particularly increased slow-wave activity and a corresponding reduction in fast-wave activity. Predictably, significant changes also occurred in mean EEG frequency and total power. No significant changes were observed in the cortical-evoked responses. EEG abnormalities were still significant one week following the completion of a course of ECT, but reverted to baseline levels within four weeks.

Computed tomographic scans in ECT-patients.

Although the safety and efficacy of electroconvulsive therapy (ECT) is acknowledged by most, concern has repeatedly been expressed that the treatment may have some lasting effects on the brain. To study potential morphological changes, 22 patients with a history of ECT were submitted to a detailed clinical evaluation and a brain CT scan examination. Age- and sex-matched control subjects comprised a group of comparable patients, none of whom had received ECT, and a second control group of healthy volunteers. Patients had larger ventricle/brain ratios and cortical "atrophy" scores than normal controls, but no association was found between these radiological measures and a previous history of ECT. Hence, the present data are consistent with recent reports that affective disorders may be associated with enlarged brain ventricles, although the clinical significance of such findings remains unclear. In line with previous investigations age correlated significantly with cortical "atrophy" scores and ventricle/brain ratios for all subjects. Statistical tests of correlations between duration of illness, previous psychotropic drug exposure and CT scan appearances were mainly inconclusive.