J. Hatzimanolis

Larger variability of saccadic reaction times in schizophrenia patients.

Slower mean reaction time (RT), known as psychomotor slowing, is well documented in patients with schizophrenia. Fewer studies have shown increased variability of RT in these patients suggesting a basic difference in the distribution of RT. In this study median RT and its variability were measured for visually guided saccades performed by 53 patients and 1089 control subjects. Then average cumulative RT distributions were derived for each group and the RT distribution for each group was modeled using a decision signal rising linearly to a threshold signaling the beginning of the visually guided saccade. There was a small increase in the median RT for patients while their RTs were much more variable from trial to trial leading to a difference in the average RT distribution of the patient group. The model application led to the conclusion that this difference in the distribution of RT for patients could be attributed to a basic difference in information processing leading to the decision to move the eyes to the visually presented target. This information-processing difference could be the result of a difference in the build-up of neuronal activity involved in the generation of visually guided saccades in the frontal cortex.

Two cases of risperidone-induced tardive dyskinesia and a review of the literature.

Acase in which a 26 year old patient with undifferentiated schizophrenia, showing abnormal oral, lingual and jaw movements suggestive of tardive dyskinesia during a dose reduction of risperidone, is presented. A second case, relating to a 39 year old married woman diagnosed as having a DSM-IV schizophreniform disorder is also presented. These two cases are discussed in relation to the existing literature.

GABAPENTIN AS MONOTHERAPY IN THE TREATMENT OF ACUTE MANIA

Two cases of mania treated with gabapentin, a new anticonvulsant, are presented. After 2 weeks of treatment a moderate improvement of both patients was observed. The antimanic effect of gabapentin awaits confirmation by systematic, well designed studies.

Clinical Features of Delusional Beliefs in Schizophrenic and Unipolar Mood Disorders: A Comparative Study

We assessed comparatively 13 clinical features of delusions in a sample of 132 deluded inpatients of both sexes with schizophrenic (n = 89) or unipolar mood disorders (n = 43). Patients with schizophrenic disorders exhibited higher levels of severity than those with unipolar depression with respect to the features of vagueness-illogicality, bizarreness, systematization, conviction, duration and affective incongruence, whereas the reverse held true with respect to the feature of emotional impact. Furthermore, the two diagnostic groups were compared to each other with respect to patients’ scores on five dimensions of their delusions obtained through factor analysis, namely emotional and behavioral impact, cognitive disintegration, delusional certainty, volitional dyscontrol and affective inappropriateness. Schizophrenic patients exhibited higher levels of severity than depressives on the second and fifth dimensions, whereas the reverse held true with respect to the fourth one. Our results suggest that particular features of delusions as well as broader dimensions thereof, may assist in the differential diagnosis of unipolar depression with psychotic features from schizophrenic disorders.

Clinical, endocrine and neurochemical effects of moclobemide in depressed patients

The clinical efficacy of the monoamine oxidase A inhibitor moclobemide and its effect on the dexamethasone suppression test (DST) and plasma and urine methoxyhydroxyphenylglycol (MHPG) were investigated in 26 depressed patients during a 4‐week clinical trial. Fourteen patients (54%) responded favourably to the treatment (50% or more reduction of the Hamilton Rating Scale for Depression score). All (8) patients with an abnormal DST responded to treatment; 11 of 16 patients with a normal DST did not respond. Patients with low pretreatment MHPG excretion, according to the median value, were more frequently treatment responders. Plasma and urine MHPG were significantly decreased by treatment. The results indicate that low excretion of MHPG and cortisol nonsuppression may be considered as predictors of favourable clinical response to moclobemide treatment.

Hormonal responses to clonidine and urinary MHPG in delusional and nondelusional melancholic patients: a placebo-controlled study

SummaryThe growth hormone (GH) and cortisol responses to intravenous clonidine (0.15mg) treatment of 25 melancholic patients, 12 with and 13 without delusions, were studied with placebo control. The baseline concentrations of the main noradrenaline metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG) were also estimated in urine. Cortisol plasma levels decreased significantly and equally after both placebo and clonidine. Baseline cortisol levels correlated positively with urinary MHPG. Clonidine did not increase GH levels significantly over time compared with placebo. Delusional melancholic patients tended to have smaller GH responses to clonidine than nondelusionals (F=2.18,P=0.06). There were no differences in GH response to clonidine between high and low MHPG excretors.

Clinical Dimensions of Delusional Beliefs: A Factor-Analytic Study

We investigated the factorial composition as well as the demographic, anamnestic and clinical correlates of 13 features of delusional beliefs in a sample of 127 psychiatric inpatients with active delusions at the time of their assessment: Six factors were extracted, jointly accounting for 67.3% of the variance, which were interpreted as the dimensions of cognitive disintegration, volitional dyscontrol, doxastic strength, distress, incongruence and expansiveness, respectively. Moreover, most factors exhibited distinctive profiles of demographic, anamnestic or clinical correlates. Overall, our findings provide supportive evidence for both the clinical multidimensionality of delusional beliefs at the factor-analytic level and the – at least partial – external validity of the factorial solution obtained.

Prolactin secretion in response to haloperidol challenge in delusional (psychotic) and non-delusional depression.

Certain studies on measures related to central neurotransmitter activity have demonstrated that in delusional (psychotic) depression there is a dopaminergic dysregulation which distinguishes it from non-psychotic depression. A neuroendocrinologic method to check the degree of DA receptor responsivity is by measuring the prolactin responses to acute intramuscular administration of haloperidol. We studied this possibility by applying the haloperidol test in seven delusional and ten non-delusional depressed patients. All patients met DSM-IV criteria for a major depressive episode, single or recurrent, with or without psychotic features. After a three-week washout period, 5 mg of haloperidol were injected i.m. and blood samples were taken at 0, 30, 60, 90 and 120 minutes. In both trials, significant time effects were observed (elevated prolactin levels, F = 11.36, P = 0.000). However, the prolactin responses to haloperidol did not differ significantly between the two patient groups (F = 0.12, P = 0.97). These data do not show a difference in D(2) receptor responsivity, at least at the hypothalamus-pituitary level, between psychotic and non-psychotic depression.

The effect of ECT on plasma cyclic nucleotides: A simulated ECT controlled study in melancholic patients

SummaryConcentrations of cAMP and cGMP in plasma were measured in 20 drug-free melancholic patients during a simulated electroconvulsive treatment (SECT) and a bilateral ECT session. Blood samples were taken every 15min beginning 15min before and ending 60min after the SECT or the ECT. Two-way ANOVA and pairedt-test demonstrated a significant and greater fall in cAMP over time following SECT. ECT induced a marginal increase (P < 0.05) at 45 min postictally. It is postulated that ECT causes an increase in cAMP levels which is masked by the decrease observed during SECT, caused presumably by the anaesthetic medication. The plasma cGMP levels were increased gradually and significantly after SECT and the same rise was observed during ECT. These effects are discussed in relation to changes in adrenergic-cholinergic activities induced by the medication and the electrical stimulus.

Thyrotropin and prolactin responses to TRH in delusional (psychotic) and nondelusional depressed patients

The thyrotropin (TSH) and prolactin (PRL) responses to protirelin (TRH) were studied in 62 female unipolar depressive alients. 24 delusional (psychotic) and 38 nondelusional (Diagnostic and Statistical Manual [DSM]-III-R criteria). The TSH response to ~H was blunted (:5 6 jllU/mL) in ten of the 24 delusional (41.6%) and in 18 of the 38 nondelusional (47.4%) patients, the difference ing not significant. The TSH and PRL responses to TRH. calculated as area under the curve, were not different between the two ~OUp5. Similar results were obtained when the response patterns were compared by repeated measure analysis of covariance.