Pd. Harvey et al., COGNITIVE-FUNCTIONING IN CHRONICALLY HOSPITALIZED SCHIZOPHRENIC-PATIENTS - AGE-RELATED-CHANGES AND AGE DISORIENTATION AS A PREDICTOR OF IMPAIRMENT, Schizophrenia research, 17(1), 1995, pp. 15-24
Although schizophrenic patients manifest cognitive impairments, there
is considerable variability across patients in the severity of this im
pairment. Very chronic patients with a poor outcome, particularly geri
atric patients, manifest the most severe impairments, which have often
been characterized as resembling dementia. This study examined age-re
lated changes in cognitive functioning in a sample of schizophrenic pa
tients (n=393) ranging from 25 to 95 years of age, with a specific foc
us on identifying aspects of performance that were impaired in the you
ngest patients and preserved in the oldest patients. Age disorientatio
n was examined hi detail because it was previously found to predict gl
obal intellectual impairment in chronic patients. All 22 test items ch
anged linearly over time (with age), with aspects of orientation, conc
entration, and delayed recall most impaired in young patients and nami
ng and sentence repetition most preserved in the oldest patients. Age
disoriented patients had more severe cognitive impairments at each age
and the age-related changes in global impairment were more severe for
these patients. The prevalence of age disorientation was consistent w
ith previous reports and a one-year retest of the sample found that ag
e disorientation was extremely stable over time within patients. The t
ypes of functions that are preserved in the oldest patients underscore
previous findings of differences between geriatric schizophrenic pati
ents and patients with degenerative diseases and the stability of age
disorientation suggests that it is a trait of a subset of schizophreni
c patients, those who appear to have the most severely declining cours
e of illness.