2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane and Schizophrenia

Drug induced parkinsonism (DIP) is directly related to dopamine D2 receptor blockade. However, there are many references describing parkinsonian signs (PS) in naive-patients. In our previous study, we observed lower DAT binding in a group of first-episode schizophrenic patients after short-term treatment with risperidone, compared with age-matched healthy controls.. To clarify if DAT decrease could be an illness trait, excluding the effect of antipsychotics on DAT availability, and to determine whether DAT availability before treatment with antipsychotics may predict subsequent development of PS.. A new series of 20 neuroleptic-naive schizophrenic patients and 15 healthy subjects was recruited. SPECT with [(123)I] FP-CIT (DaTSCAN(R)) was performed before starting antipsychotics and after 4 weeks of treatment. PS and psychopathological status were assessed by the Simpson-Angus (SAS), CGI and PANSS scales. Quantitative analyses of SPECTs were performed using ROIs placed in the caudate, putamen and occipital cortex.. Schizophrenic patients showed lower DAT binding compared with the healthy subjects at baseline (p<0.001) and after a 4-week-treatment period (p=0.001). Six out of eight schizophrenic patients of the DIP group were symptomatic for PS at baseline, in comparison to two out of 12 in the NoDIP group. Nonetheless, no differences were observed on DAT between DIP and NoDIP, neither at baseline (p=0.360) nor at endpoint (p=0.984). Finally, no differences between baseline-endpoint DAT binding were observed, neither in the DIP group (p=0.767) nor in the NoDIP group (p=0.093).. Our new series of first-episode naive-schizophrenic patients (1) points out DAT dysfunction as an illness trait due to the significantly lower DAT binding in schizophrenic patients in comparison to healthy subjects; (2) supports the results of other authors who describe PS in never-treated patients; (3) confirms that [(123)I] FP-CIT does not allow us to predict which patients will develop parkinsonism due to the lack of differences between DIP and NoDIP patients; and (4) confirms a null effect of antipsychotics on DAT due to the lack of differences in [(123)I] FP-CIT before and after a 4-week-treatment period.

Topics: Adult; Antipsychotic Agents; Caudate Nucleus; Dopamine Plasma Membrane Transport Proteins; Down-Regulation; Female; Humans; Male; Neostriatum; Parkinson Disease, Secondary; Psychiatric Status Rating Scales; Putamen; Risperidone; Schizophrenia; Schizophrenic Psychology; Severity of Illness Index; Tomography, Emission-Computed, Single-Photon; Tropanes

Similarly to subjects with degenerative parkinsonism, (123)I-FP-CIT SPECT has been reported either normal or abnormal in patients with drug-induced parkinsonism (DIP), challenging the notion that parkinsonism might be entirely due to post-synaptic D2-receptors blockade by antipsychotic drugs. In a previous multicenter cross-sectional study conducted on a large sample of patients with schizophrenia, we identified 97 patients who developed parkinsonism with a similar bi-modal distribution of DAT-SPECT. In this longitudinal study, we reported clinical and imaging features associated with progression of motor disability over 2-year follow-up in 60 out of those 97 patients with schizophrenia and parkinsonism who underwent (123)I-FP-CIT SPECT at baseline evaluation (normal SPECT=33; abnormal SPECT=27). As second end-point, chronic response to levodopa over a 3-month period was tested in a subgroup of subjects. Motor Unified Parkinson's Disease Rating Scale (UPDRS) at follow-up significantly increased in patients with abnormal SPECT. Specifically, a 6-point worsening was demonstrated in 18.5% of the subjects with abnormal SPECT and in none of the subjects with normal SPECT. Levodopa treatment improved motor UPDRS only in the group with abnormal SPECT. After adjustment for possible confounders, linear regression analysis demonstrated that abnormal SPECT findings at baseline were the only predictor of motor disability progression and of better outcome of levodopa treatment. Our results support the notion that a degenerative disease might underlie parkinsonism in a minority of schizophrenic patients chronically exposed to antipsychotics. Functional imaging of the dopamine transporter can be helpful to select this patient sub-group that might benefit from levodopa therapy.

Topics: Adult; Age Factors; Aged; Chi-Square Distribution; Disease Progression; Dopamine Agents; Dopamine Plasma Membrane Transport Proteins; Female; Humans; Levodopa; Longitudinal Studies; Male; Middle Aged; Parkinsonian Disorders; Predictive Value of Tests; Protein Binding; Schizophrenia; Severity of Illness Index; Tomography, Emission-Computed, Single-Photon; Tropanes

Drug-induced parkinsonism (DIP) in patients treated with antipsychotic drugs is considered a form of post-synaptic parkinsonism, caused by D2-receptor blockade. Recent studies, however, carried out on small and heterogeneous patient samples, have shown that DIP may be associated with [(123)I]FP-CIT single photon emission computed tomography (SPECT) abnormalities, which are markers of dopamine nigrostriatal terminal defect. In the present study, outpatients fulfilling the DSM-IV criteria for schizophrenia and treated with antipsychotics for at least 6 months, were enrolled in order to estimate the prevalence of DIP and, among patients with DIP, the prevalence of [(123)I]FP-CIT SPECT abnormalities. Socio-demographic and clinical variables associated with the presence of DIP and SPECT abnormalities were also assessed. DIP was diagnosed in 149 out of 448 patients with schizophrenia (33%). Age, use of long-acting antipsychotics and a positive family history of parkinsonism were the only demographic variables significantly associated with the development of DIP. Neuroimaging abnormalities were found in 41 of 97 patients who agreed to undergo [(123)I]FP-CIT SPECT (42%). Only age differentiated this group of patients from those with normal imaging. These preliminary findings suggest that D2-receptor blockade may coexist with a dopamine nigrostriatal terminal defect, as assessed by [(123)I]FP-CIT SPECT abnormalities, in a relevant proportion of DIP patients. Longitudinal studies should be designed with the aim of improving our understanding of the mechanisms of pre-synaptic abnormalities in DIP patients and identifying specific treatment strategies.

Topics: Adult; Aged; Antipsychotic Agents; Brain; Brain Mapping; Female; Humans; Male; Middle Aged; Parkinson Disease, Secondary; Schizophrenia; Sex Factors; Statistics, Nonparametric; Tomography, Emission-Computed, Single-Photon; Tropanes

A 58-year old woman with chronic schizophrenia developed worsening parkinsonian symptoms over the previous 6 years, and was eventually diagnosed as having Parkinson's disease. Antipsychotics were stopped because they worsened these symptoms. Antiparkinsonian treatment led to a significant increase in delusions and behavioural disorganisation. The patient underwent electroconvulsive-therapy which improved both her psychiatric and motor symptoms. After treatment, 123I-Ioflupane uptake was mildly increased in the left caudate nucleus, but uptake in right caudate nucleus was lower than in a pretreatment scan.

Topics: Caudate Nucleus; Dopamine Plasma Membrane Transport Proteins; Electroshock; Female; Humans; Middle Aged; Nortropanes; Parkinson Disease; Schizophrenia; Tomography, Emission-Computed, Single-Photon

Alterations in the dopaminergic system have long been implicated in schizophrenia. A key component in dopaminergic neurotransmission is the striatal dopamine transporter (DAT). To date, there have been no longitudinal studies evaluating the course of DAT in schizophrenia. A 4-year follow-up study was therefore conducted in which single photon emission computed tomography was used to measure DAT binding in 14 patients and 7 controls. We compared the difference over time in [(123)I] FP-CIT striatal/occipital uptake ratios (SOUR) between patients and controls and the relationship between this difference and both symptomatology and functional outcome at follow-up. We also calculated the relationship between baseline SOUR, symptoms and functional outcome at follow-up. There were no statistically significant differences between patients' SOUR changes over time and those of controls. A significant negative correlation was observed between patients' SOUR changes over time and negative symptomatology at follow-up. A significant negative correlation was also found between baseline SOUR in patients and negative symptomatology, and there was a significant association between lower SOUR at baseline and poor outcome. Although the study found no overall differences in DAT binding during follow-up between schizophrenia patients and controls, it demonstrated that differences in DAT binding relate to patients' characteristics at follow-up.

Topics: Adult; Corpus Striatum; Dopamine Plasma Membrane Transport Proteins; Female; Humans; Longitudinal Studies; Male; Occipital Lobe; Psychiatric Status Rating Scales; Schizophrenia; Tomography, Emission-Computed, Single-Photon; Tropanes; Young Adult

Topics: Aged; Humans; Iodine Isotopes; Male; Parkinson Disease; Psychotic Disorders; Schizophrenia; Tomography, Emission-Computed, Single-Photon; Tropanes

Drug-induced parkinsonism (DIP) is one of the main causes of treatment drop-out in schizophrenic patients causing a high incidence of relapse that leads patients to a bad clinical prognosis. The dopaminergic nigrostriatal pathway is involved in the movement control, so the study of the dopamine transporter (DAT) could be of great value to determine its implication in the appearance of DIP.. The goal of the study is to determine the striatal DAT binding assessed with [(123)I] FP-CIT SPECT in first-episode neuroleptic-naive schizophrenic in-patients with DIP after short-term antipsychotic treatment.. The [(123)I] FP-CIT binding ratios of ten schizophrenic in-patients who developed DIP during the first 4-week period of risperidone treatment (6+/-2 mg/day) were compared with ten schizophrenic in-patients treated with the same doses of risperidone and who do not developed DIP and with ten age-matched healthy subjects. Quantitative analyses of SPECTs were performed using regions of interest located in caudate, putamen and occipital cortex. Parkinsonism was assessed by the Simpson-Angus Scale and the psychopathological status by the Clinical General Impression and Positive and Negative Syndrome Scales.. Whole striatal [(123)I] FP-CIT binding ratios were significantly lower in patients with and without DIP than in healthy subjects (p<0.001). This was also observed in whole putamen (p<0.001) and caudate nucleus (p<0.001). Females showed higher whole striatal [(123)I] FP-CIT binding ratios than males (p<0.05). No differences in psychopathological scales were observed between patients with and without DIP.. Our first-episode schizophrenic patients with and without DIP after short-term risperidone treatment have a decreased striatal DAT binding assessed with [(123)I] FP-CIT. This alteration could be related to the schizophrenic disease or may be secondary to the antipsychotic treatment.

Topics: Adult; Antipsychotic Agents; Binding, Competitive; Humans; Iodine Radioisotopes; Neostriatum; Parkinson Disease, Secondary; Schizophrenia; Time Factors; Tomography, Emission-Computed, Single-Photon; Tropanes

Disturbances in the dopamine (DA) system are thought to play a major role in schizophrenia. Amphetamine-induced release of endogenous DA is shown to be enhanced in schizophrenia, as is striatal [18F]FDOPA uptake in the striatum. It is not clear if the density of DA neurons is altered in schizophrenia. By studying the DA transporter with [123I]FP-CIT single photon emission computed tomography (SPECT), the density of nigrostriatal dopaminergic cells can be studied. Using [123I]FP-CIT SPECT, DA transporter density in the striatum was studied in 36 young patients with schizophrenia. Ten patients were antipsychotic (AP)-naive, 15 were treated with olanzapine, eight with risperidone and three were AP-free. A control group of 10 age-matched volunteers was included. Striatal [123I]FP-CIT binding was not significantly different between AP-naive patients (2.87), patients treated with olanzapine (2.76), patients treated with risperidone (2.76), AP-free patients (2.68) and controls (2.82) (F=0.07,p=0.98). Unexpectedly, striatal [123I]FP-CIT binding in females was significantly higher than in males (3.29 and 2.70, respectively; t=-2.56, p=0.014).Concluding, functional changes in the dopaminergic system in schizophrenia are not likely to be reflected in a change in DA transporter density. Moreover, DA transporter density does not seem to be altered by AP medication.

Topics: Adult; Benzodiazepines; Brain Mapping; Carrier Proteins; Corpus Striatum; Dopamine Plasma Membrane Transport Proteins; Female; Humans; Iodine Radioisotopes; Male; Membrane Glycoproteins; Membrane Transport Proteins; Nerve Tissue Proteins; Neural Pathways; Olanzapine; Pirenzepine; Risperidone; Schizophrenia; Substantia Nigra; Tomography, Emission-Computed, Single-Photon; Tropanes