David Mayerhoff

Methylphenidate increases thought disorder in recent onset schizophrenics, but not in normal controls

The effects of apomorphine and methylphenidate on thought disorder, as measured by the Thought Disorder Index, in schizophrenic patients and in normal controls were evaluated. Methylphenidate, but not apomorphine, increased thought disorder in patients. Neither drug significantly increased thought disorder in controls.

Clozapine response in treatment-refractory first-episode schizophrenia

We examined the response to clozapine in 10 schizophrenic patients who had been followed prospectively from the time of their first hospitalization and who were refractory to multiple clinical trials with typical neuroleptics

Mood responses of remitted schizophrenics to methylphenidate infusion

To investigate the mood response of schizophrenic subjects to psychostimulant challenge, 29 neuroleptic-treated subjects (22 with schizophrenia and 7 with schizoaffective disorder) in clinical remission received two infusions, one with methylphenidate 0.5 mg/kg and the other with normal saline, under double-blind conditions. Twenty-five of these subjects were withdrawn from neuroleptics and given a second set of double-blind infusions. Infusion mood responses were classified as euphoric, neutral, mixed or dysphoric. Subjects were also rated as either psychotic symptom activators to the infusion or no change in psychotic symptoms. Overall response by mood category was as follows: 35.2% euphoric, 50% neutral, 5.6% mixed and 9.3% dysphoric. Mood responses were not correlated with sex, methylphenidate plasma levels or diagnostic distinctions between schizophrenia and schizoaffective disorder. Although they occurred infrequently, dysphoric and mixed mood responses were associated with high rates of psychotic activation. Comparing subjects on and off neuroleptics, subjects on neuroleptics had more euphoric responses than the same subjects off neuroleptics. This increased number of euphoric responses in subjects taking neuroleptics compared to off neuroleptics suggests that neuroleptic treatment status may be an important factor in assessing psychostimulant use in schizophrenia patients.

Assessing Intimidation Using a Brief Intrusiveness Measure

Aims: Patient intrusiveness has been associated with violence in psychiatric services and perceived intrusiveness may undermine therapeutic environments even without threatened violence. We assessed whether this construct was considered useful and quantifiable in a State Hospital setting. Methods: Staff members were asked to rate their perceptions of the intrusiveness of each patient using a single Likert-type item. Results: Staff from multiple disciplines found the indicator to have face validity and to be readily scorable. Ratings among staff varied moderately as did repeated ratings. The measure showed significant, albeit modest, associations with aggressive incidents (r=0.50; p<0.01). It appeared to track positive environmental change on the unit over time. Clinical Implications: Intrusiveness warrants investigation as an independent construct. The readily administered indicator shows promise for assessing patient and staff needs.

Behavioural effects of IV MCPP in schizophrenia

The effect of the serotonergic system on psychotic behaviour and sehizophrenia has been recently studied. Meta-chlorophenylpiperazine (MCPP) is a direct-acting 5HT receptor agonist which has been shown to have both neurochemical and behavioural effects in schizophrenic subjects. In this study, we report the behavioural effect of I.V. MCPP administration in a cohort of new-onset and chronic schizophrenics. clozapine trial. Patients were rated for the presence of psychopathological and tardive dyskinesia at regular intervals. Plasma and cerebrospinal fluid homovanillic acid (pHVA, CSF HVA) and cerebrospinal 5hydroxyindoleacetic acid (CSF SHIAA) levels were collected at baseline and treatment week 3. Data from 19 DSM III schizophrenic and schizoaffective disorder patients were examined. The sample was 68% male, 88% treatment refractory, 53% had tardive dyskinesia and the mean age was 29.5k6.3 years. Dividing the sample into clozapine responders vs nonresponders showed that the responders had both a lower baseline CSF HVA levels (pc.08) and a CSF HVA/SHIAA ratio (pi.04). Plasma HVA levels were not associated with CSF HVA values but with CSF SHIAA levels.