THERAPY OF MENTAL
ILLNESS IN LATE LIFE
Ewald W. Busse
PRIOR to the selection and implementation of a therapeutic plan for the treatment of mental illness, it is necessary to establish the proper diagnosis and to have an understanding of the disease. The clinician should know as much as possible about the disease process, the prognosis, the various biological and environmental factors that influence the course of the disorder, and the effectiveness of treatment. This is consistent with the multiarial approach of DSM-III. 58 There are no mental disorders that occur exclusively in late life. There are, however, a number that are more common to the latter part of the life span, after the age of sixty-five. These include organic mental disorders and affective disorders, namely depression, paranoia, hypochondriasis, and sleep disturbances.
The percentage of the population in the United States of persons over the age of sixtyfive has increased steadily, from 4.1 percent in 1900 to 8.1 percent in 1950; 9.8 percent in 1970; 10.3 percent in 1975; and 11 percent in 1980. If current trends continue, the percentage of the older population will be 11.7 percent in the year 2000 and 16.1 percent in 2050. 7
Computed from death rates in 1977, the average life expectancy at birth for both sexes combined was 73.2 years. For males, it was 69.3 years and for females, 77.1 years, a difference of 7.8 years. At age sixty-five the remaining expected years of life for women are 18.3 years and for men 13.9 years, a difference of 4.4 years. If recent decreases in death rates continue, especially from cardiovascular conditions, life expectancies will increase even further. This may not, however, improve the quality of life, as it is possible that more individuals will develop senile dementia or related organic mental diseases. 6
Statisticians and epidemiologists frequently refer to persons sixty-five years of age or over as "the older population." However, from a health standpoint those sixty‐