Biological and psychological predictors of survival in a psychogeriatric population

Out of 206 geriatric subjects who had been assessed with respect to a number of biological and psychological features (Müller & Grad, 1974), it was possible to reach 180 (or 87%) for a 5-year follow-up. Associations of these previous data to six survival categories were examined in order to explore their prognostic value. Of the biological variables the amount of slow EEG activity showed the greatest predictive power concerning the chances of survival, with only a few subjects, who had shown a slow EEG originally, alive after 5 years. Several other biological variables also showed significant differences between survivors and nonsurvivors; the plasma cortisol levels which were determined after the EEG test were lower in the survivors. Diagnostic and predictive value of routine electroencephalographic examinations in geropsychiatric assessments is emphasized. The close relationship of psychological and biological factors is discussed in the context of a dynamic concept of organic brain syndromes.