Sue Thiemann

Depression, parkinsonian symptoms, and negative symptoms in schizophrenics treated with neuroleptics.

To determine whether depression and neuroleptic-induced parkinsonism confound the clinical assessment of negative symptoms in schizophrenics, we evaluated 45 outpatient schizophrenics for depression, parkinsonian symptoms, and negative symptoms using standard clinical rating scales. Neuroleptic and anticholinergic dose and plasma activity were also determined. Associations between negative symptoms and these clinical and drug variables were examined using a multivariate statistical model. Negative symptoms were significantly correlated with several parkinsonian symptoms, some vegetative features of depression, and with anticholinergic dose. No significant correlations were found between negative symptoms and cognitive features of depression, or neuroleptic and anticholinergic plasma activity. These findings suggest that assessment criteria for negative symptoms, depression, and drug-induced parkinsonism overlap in treated schizophrenics. Strategies for differentiating these clinical syndromes are discussed.

Rating scales in research: The case of negative symptoms

Two measures of negative schizophrenic symptoms, the Scale for the Assessment of Negative Symptoms and the withdrawal-retardation subscale of the Brief Psychiatric Rating Scale, are found to be redundant when used together. Studies incorporating redundant measures have numerous disadvantages. Using multiple scales increases the cost and effort for the investigator, places a greater burden on research subjects, and compromises the interpretability of findings by increasing the probability of both Type I and Type II errors. A strategy for evaluating the use of multiple rating scales is suggested, and the theoretical basis of this strategy is discussed.

Central error-correcting behavior in schizophrenia and depression

A previous study suggested that schizophrenic subjects exhibit an impaired ability to correct their own errors of movement without using exteroceptive signals. However, the performance of schizophrenic subjects was compared to that of only one other psychiatric group (alcoholic subjects), and a relatively small number of subjects was studied. To investigate the specificity of the postulated impairment, 9 schizophrenic, 11 depressed, and 8 normal subjects performed a tracking task designed to prevent the use of exteroceptive cues in correcting errors of movement. The depressed and normal groups did not differ significantly on any performance measure, but the schizophrenic subjects again demonstrated a gross impairment in correcting errors, yet no impairment in initiating correct responses. These findings suggest that the impaired ability to monitor ongoing motor behavior on the basis of internal, self-generated cues may be specific to schizophrenia among major psychiatric disorders.

Desglycinamide-9-arginine-8-vasopressin (DGAVP, Organon 5667) in patients with dementia☆

Vasopressin peptides have been shown to facilitate learning and memory in both animals and humans; however, the effectiveness in humans is controversial. In a double blind parallel group study, 17 demented subjects (either Alzheimers or alcoholic) were given either desglycinamide-9-arginine-8-vasopressin (DGAVP) 92 micrograms intranasally TID or an identical placebo for 1 week after having received 1 week of placebo. To our knowledge, this is the first report of DGAVP being used in subjects with dementia. The DGAVP group had a statistically significant improvement on the Buschke list learning of low imagery words. However, for various reasons discussed in the paper, we feel this finding needs to be replicated before any definite conclusions can be drawn. Since there were no other appreciable behavioral effects of this DGAVP regimen, our results should be considered negative. There was no evidence of any DGAVP-related adverse effects, except for possible weight gain.