Richard D. Sanders

Factor structure of neurologic examination abnormalities in unmedicated schizophrenia.

The heterogeneity and uncertain significance of neurologic exam abnormalities in schizophrenia prompted us to evaluate their factor structure. We administered a modified version of the Neurological Evaluation Scale (NES) to 103 unmedicated patients with schizophrenia. Data were distilled by combining right- and left-side scores, and by eliminating superfluous, rarely abnormal and unreliable items from the analysis. Exploratory principal components analysis yielded four factors: repetitive motor tasks (fist-ring, fist-edge-palm, alternating fist-palm, dysdiadochokinesis); cognitive-perceptual tasks (memory, audiovisual integration, right-left orientation, face-hand test, rhythm tapping reproduction); balancing tasks (Romberg, tandem gait); and the palmomental reflex. Evaluation of the relationship between these factors and clinical and demographic variables revealed a robust correlation between the cognitive-perceptual factor and full-scale IQ score. This analysis is a step toward developing empirical subscales of a modified NES, which may provide insights into the nature of neurologic impairment in schizophrenia and may prove clinically useful.

Frontal lobe metabolism and cerebral morphology in schizophrenia: 31P MRS and MRI studies.

The relation between frontal lobe membrane phospholipid metabolism as measured by 31Phosphorus magnetic resonance spectroscopy (31P MRS) and cerebral morphology as measured on magnetic resonance images (MRI) was examined in nine first episode neuroleptic naive schizophrenic patients. Total corpus callosal area was significantly correlated with phosphodiester concentration. When examined separately, this relation was confined to the rostral quartile (genu) of the corpus callosum. The pathophysiological significance of this finding is discussed in relation to neurodevelopmental hypotheses of schizophrenia.

Are neurologic examination abnormalities heritable? A preliminary study.

BACKGROUND Neurologic examination abnormalities (NEA) are more prevalent among patients with schizophrenia as well as their unaffected relatives when compared with healthy controls, suggesting that NEA may be endophenotypes for schizophrenia. We estimated the heritability of NEA in moderately sized pedigrees. We also evaluated correlations between NEA and cognitive performance in order to examine their construct validity. METHODS Members of eight extended families, each consisting of two first degree relatives with schizophrenia/schizoaffective disorders, as well as available first- to fifth-degree relatives were examined (n=96 participants). A modification of the Neurological Evaluation Scale (NES) was employed, augmented with localizing signs. Where feasible, we used untransformed data such as error counts and completion time, rather than ordinal measures. Heritability was estimated using the variance component method, implemented in SOLAR. RESULTS Statistically significant heritability (h2) estimates were obtained for several measures (p<0.05, h2+/-standard error: rapid alternating movements, right-sided completion time, 0.99+/-0.19; alternating fist-palm test, completion time, 0.77+/-0.19 s, errors, 0.70+/-0.32; fist-ring test, right-sided completion time, 0.53+/-0.23 s, left-sided completion time, 0.70+/-0.21 s; go-no go task, correct responses, 0.93+/-0.33; audio-visual integration, correct responses, 0.79+/-0.54). For most items, heritability analysis was hampered by insufficient data variability (infrequent errors). Correlational analyses show some degree of divergence among types of NEA, repetitive motor tasks being associated with most domains of cognitive functioning other than executive functioning, and cognitive-perceptual tasks being associated with memory and executive functioning. CONCLUSIONS Significant familial influences on certain aspects of neurologic performance were detected. These heritable measures were also correlated with heritable neurocognitive measures.

Inter-rater reliability of the neurological examination in schizophrenia.

Neurological Examination Abnormalities (NEA) are prevalent in schizophrenia, but the significance of this is obscured by methodological problems. The Neurological Evaluation Scale (NES), the most widely used structured neurological examination in schizophrenia research, has had limited study of its inter-rater reliability (IRR). An augmented version of the NES was jointly administered (one examiner-rater and one observer-rater) by three pairs of psychiatrists to two populations of patients with idiopathic psychotic disorders. In addition to the ordinal and categorical data yielded by the original NES, continuous data were recorded in one of the series. Reliability analyses of our populations and a previously published study, reveal consistently adequate IRR in 12 of the 26 items assessed, and inconsistently adequate IRR in an additional 11. Consistent with studies using other NEA schedules, IRR was unacceptably low for some items that rely on subjective severity ratings. Certain rare abnormalities, which posed difficulties for the estimation of IRR, are probably not generally useful in the study of schizophrenia. Reliability estimates of continuous, ordinal and dichotomous data were comparable in most cases. We recommend that certain items from the NES be deleted, and that other studies of NEA in psychiatry follow similar procedures before undertaking further analyses.

An Open Trial of Olanzapine in Patients With Treatment-refractory Psychoses

Olanzapines structural similarities to clozapine and the results of premarketing clinical trials suggested potential usefulness in treating patients with treatment-refractory psychoses. Sixteen inpatients from the state hospital with severe, refractory schizophrenic or schizoaffective psychoses received olanzapine in a prospective, 12-week, open-label trial. The olanzapine dose was 10 mg/day for at least the first 6 weeks and never exceeded 20 mg/day. Mood stabilizers and other antipsychotic agents were discontinued before olanzapine was started. Patients frequently became more agitated within the first several weeks of initiating treatment, requiring the increased use of benzodiazepines and often leading to the discontinuation of olanzapine. Two patients improved significantly. Overall, significant clinical improvement was noted only for motor side effects. This study concluded that olanzapine was not effective in this heterogeneous group with chronic, severe, treatment-resistant psychosis when used in this manner. Further research is needed to explain the tendency toward agitation upon transition to olanzapine, which is reminiscent of reported risperidone complications. Clinicians should be alert for this complication and should minimize concomitant medication changes that might add to the risk of emergent agitation.

The Effects of Antipsychotic Medication on Factor and Cluster Structure of Neurologic Examination Abnormalities in Schizophrenia

This study extends a previous study of the factor structure of the neurologic examination in unmedicated schizophrenia, utilizing cluster analysis and adding a medicated condition. We administered a modified version of the Neurologic Evaluation Scale (NES) on two occasions to 80 patients with schizophrenia or schizoaffective disorder, once while on antipsychotic medications and once while off medication. Data were distilled by combining right- and left-side scores, and by excluding rarely abnormal and unreliable items from the analysis. Principal components analysis yielded an intuitive four-factor solution in the unmedicated condition, but an inscrutable five-factor solution during medication. Cluster analysis revealed three groups: normal, cognitively impaired, and diffusely impaired. These results were also less interpretable with data from the medicated condition. Neurologic performance was better in the medicated than in the unmedicated condition. As is the case with other domains of symptoms and performance in schizophrenia, relationships among neurologic exam variables are altered by the presence of antipsychotic medication.

Sensory-perceptual dysfunction in patients with schizophrenia and comorbid alcoholism.

We studied the effects of aging and comorbid alcoholism on sensory-perceptual dysfunction in patients with schizophrenia. Using sensory-perceptual tests from the Halstead-Reitan Neuropsychological Battery included in the Russell, Neuringer, and Goldstein (1970) Perceptual Disorders Index, samples were compared of 54 patients with comorbid schizophrenia and alcoholism, 234 patients with schizophrenia but no history of alcoholism, 132 patients with chronic alcoholism and 171 patient controls. Data were analyzed by one-way analyses of variance followed by Scheffe multiple comparison tests. Numerous significant differences were found among groups, with the comorbid schizophrenia group doing more poorly than the other groups on measures of touch perception and suppression, finger agnosia, and fingertip number writing. Multiple regression analyses using the sensory-perceptual tests as predictor variables and age as the dependent variable indicated that the strength of association between age and the multivariate set of sensory-perceptual test scores was greater in the comorbid schizophrenia group than the noncomorbid schizophrenia, alcoholism and patient control groups. The preponderance of age-related deficits was left-sided, suggesting accelerated decline in right hemispheric function. A comparison of groups across ages on a single Perceptual Disorders Index score showed a substantially larger age effect in the comorbid schizophrenia group relative to the other groups.