Subject(s)
Activities of Daily Living , Antipsychotic Agents/adverse effects , Clozapine/adverse effects , Adult , Conscious Sedation , Female , Humans , MaleABSTRACT
No disponible
Subject(s)
Humans , Male , Female , Adult , Activities of Daily Living , Antipsychotic Agents/adverse effects , Clozapine/adverse effects , Conscious SedationABSTRACT
Levels above 75% of striatal dopamine 2 receptor occupancy (D2RO) have been associated with extrapyramidal symptoms (EPS). The aim of the present study is to investigate the relationship between D2RO and EPS in a sample of psychotic patients in current treatment with both typical and atypical antipsychotics. Brain iodine-123-iodobenzamide single photon emission computed tomography ((123)I-IBZM SPECT) was performed in 81 patients taking stable doses of haloperidol, risperidone, olanzapine, quetiapine, clozapine or ziprasidone. First, the degree of D2RO and Positive and Negative Syndrome Scale (PANSS) scores was compared between the group of patients who presented EPS and the group free of EPS. Afterwards, these variables were compared among the different antipsychotic medications. The group with EPS presented means of D2RO significantly higher than the group free of EPS. Significant differences in D2RO were found in clozapine, quetiapine and ziprasidone groups compared with the haloperidol group. No differences were observed between either olanzapine or risperidone and haloperidol. No quetiapine- or clozapine-treated patients developed EPS. Haloperidol and risperidone demonstrated a relationship between striatal D2RO and EPS. The findings suggest that higher D2RO is related to appearance of EPS. Occupancy in the group with EPS was in agreement with previous studies that suggested a high degree of D2RO is necessary for the occurrence of EPS.
Subject(s)
Antipsychotic Agents/adverse effects , Basal Ganglia Diseases/metabolism , Corpus Striatum/metabolism , Psychotic Disorders/metabolism , Receptors, Dopamine D2/metabolism , Adult , Antipsychotic Agents/therapeutic use , Basal Ganglia Diseases/chemically induced , Basal Ganglia Diseases/diagnostic imaging , Corpus Striatum/diagnostic imaging , Female , Humans , Male , Psychotic Disorders/diagnostic imaging , Psychotic Disorders/drug therapy , Tomography, Emission-Computed, Single-PhotonABSTRACT
The biological basis of the association between cannabis-induced dopamine dysregulation and psychosis remains poorly understood. This (123)I-IBZM SPECT study assessed striatal dopamine D2 receptor (D2R) binding in 37 untreated first-episode psychosis (FEP) subjects, and 18 healthy controls. The aim was to examine if there were differences between FEP subjects with (n=14) and without (n=23) cannabis use in uptake ratios in the D2R. Striatal/Frontal cortex (S/F) uptake ratios were obtained. Healthy controls showed the lowest D2R binding ratios. No differences were found in S/F ratios between users and non-users, suggesting similar dopaminergic mechanisms underlying psychotic symptoms in both groups.
Subject(s)
Cannabis/metabolism , Corpus Striatum/diagnostic imaging , Psychotic Disorders/diagnostic imaging , Psychotic Disorders/pathology , Receptors, Dopamine D2/metabolism , Adolescent , Adult , Analysis of Variance , Benzamides , Dopamine Antagonists , Female , Humans , Male , Prospective Studies , Psychotic Disorders/metabolism , Pyrrolidines , Statistics, Nonparametric , Tomography, Emission-Computed, Single-Photon , Young AdultABSTRACT
There is as yet no definite prognostic marker to determine whether a first-episode psychosis will become schizophrenia or not. The aim of the present study is to address whether the mechanism of sensitization of the subcortical dopaminergic pathway - yielding to an increase of the postsynaptic D2 receptors - may serve as a prognostic marker of clinical outcome in drug naïve patients with a first-episode psychosis, by means of a prospective and multicentric study with untreated first-episode psychosis patients (n=37). 123I-IBZM SPECT was performed at the time of the inclusion in the study, before antipsychotic medication was initiated. One year later, patients were assessed again so as to determine their diagnosis. There was a significant group effect at baseline in D2 Striatal/Frontal (S/F) ratios (F=10.2, p<0.001). Bonferroni posthoc comparisons attested significant differences between diagnosis (p=0.006), and between schizophrenia and control groups (p<0.001) but no differences between non-schizophrenia and control groups (p=0.9). The logistic regression model showed that D2R binding (p=0.02) and PAS (Premorbid Adjustment Scale) adulthood score (p=0.03) were predictive of the final diagnosis (schizophrenia/non-schizophrenia; Nagelkerke R(2)=0.59; X(2)=11.08, p=0.001). These findings replicate previous results on the usefulness of D2R binding as an objective prognostic parameter, together with the evaluation of premorbid adjustment, of the evolution of first-episode psychosis. In this regard, the results may provide a new view in the approach of early and personalized treatment in the debut of a psychosis.
