Biomedical subjects

Eduard Parellada

Publications and source records attributed to Eduard Parellada.

7 recordsLinked to original sources

PubMed2006

Dopamine transporter (DAT) genotype (VNTR) and phenotype in extrapyramidal symptoms induced by antipsychotics.

INTRODUCTION: Impaired dopamine transporter (DAT) function may be involved in antipsychotic (AP)-induced extrapyramidal symptoms (EPS). A polymorphism involving a variable number of tandem repeats (VNTR) has been described in the DAT gene (SLC6A3). OBJECTIVE: We studied whether the SLC6A3 VNTR polymorphism is a risk or protection factor for AP-induced EPS. We also investigated the relationship between the polymorphism and DAT availability in the schizophrenic patient's brain. METHODS: Sixty-one patients receiving AP therapy participated in the EPS study. Of these, thirty-two cases presented EPS (Simpson-Angus >3) and twenty-nine without EPS (Simpson-Angus < or =3). The DAT expression was studied in fifteen AP-naive patients by [(123)I] FP-CIT SPECT. RESULTS: No significant differences were observed for the more common alleles ((*)9R and (*)10R) or for genotype frequencies between patients with EPS and those without EPS. The frequency of the (*)9R and (*)10R alleles was similar to that described in other European populations. There were no significant differences in striatal DAT binding among the three major VNTR genotype groups. CONCLUSIONS: Our results suggest that the VNTR polymorphism did not influence AP-induced EPS and did not affect DAT gene expression or protein function.

Adult↗

PubMed2006

Lower striatal dopamine transporter binding in neuroleptic-naive schizophrenic patients is not related to antipsychotic treatment but it suggests an illness trait.

INTRODUCTION: 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. AIM: 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. MATERIALS AND METHODS: 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. RESULTS: 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). CONCLUSION: 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.

Adult↗

PubMed2006

Clinical experience and management considerations with long-acting risperidone.

BACKGROUND: Risperidone is the first atypical anti-psychotic available in a long-acting injectable formulation. OBJECTIVE: To provide an overview of the initial clinical experience gained with long-acting risperidone during clinical trials and in general treatment, including specific case studies, as well as providing practical advice on how to initiate treatment with this new drug. METHODS: Studies published between January 2002 and June 2005 that evaluated the pharmacokinetics, efficacy and safety of long-acting risperidone for the treatment of schizophrenia were reviewed, as identified from literature searches using Medline and EMBASE. Although not peer-reviewed, abstracts and posters on long-acting risperidone presented at key psychiatry and schizophrenia congresses during this period were also reviewed where available in the public domain. RESULTS: Clinical studies have consistently demonstrated that long-acting risperidone, available in dosage strengths of 25, 37.5 or 50 mg, given once every 2 weeks, is both effective and well tolerated in patients with schizophrenia. Furthermore, significant and sustained clinical improvement has been reported in patients switched to long-acting risperidone from other oral and long-acting antipsychotic agents. Several patients groups, including the young, the elderly and patients with schizoaffective disorder, have also been shown to derive significant benefit from long-acting risperidone. CONCLUSION: A wide variety of patient groups may benefit from treatment with long-acting risperidone, including patients with suboptimal efficacy, particularly as a result of partial compliance, patients experiencing side-effects with another antipsychotic agent or those with a first episode of schizophrenia. Furthermore, long-acting risperidone, with its assured medication delivery, should improve patient compliance and assist patients in achieving remission, an important step towards functional recovery.

Adult↗

PubMed2005

Efficacy and safety of direct transition to risperidone long-acting injectable in patients treated with various antipsychotic therapies.

The maintained antipsychotic efficacy of risperidone long-acting injectable (RLAI) was investigated in patients with schizophrenia or other psychoses who were transitioned directly from their previous antipsychotic medication. Patients symptomatically stable, but considered to require a treatment change, received 25 mg of RLAI (increased to 37.5 or 50 mg, if necessary) every 2 weeks for 6 months. Assessments included Positive and Negative Syndrome Scale (PANSS), Clinical Global Impression-Severity (CGI-S), Global Assessment of Functioning (GAF), SF-36 Health-Related Quality of Life Questionnaire and Extrapyramidal Symptoms Rating Scale (ESRS). Of 1876 patients enrolled, 74% completed the 6-month study. The most frequent reasons for treatment change were non-compliance (38%), insufficient efficacy (33%) and side-effects (26%). There was a significant reduction from baseline to endpoint in mean total PANSS score and in the scores on all PANSS subscales and symptom factors (P<0.001). CGI-S improved significantly, as did mean GAF score, all factors on the SF-36 and patient satisfaction with treatment. Scores on ESRS showed significant, sustained improvements throughout the study period. Direct initiation of RLAI was effective and well tolerated. RLAI provides an advancement in the treatment options available for a wide range of patients requiring long-term antipsychotic therapy.

Adolescent↗

PubMed2004

Lack of sex differences in striatal dopamine D2 receptor binding in drug-naive schizophrenic patients: an IBZM-SPECT study.

Differences in antipsychotic treatment response, clinical course and outcome of schizophrenia could be related to gender-related cerebral differences in anatomy and function. The aim of the study was to assess sex differences in the striatal dopamine D2 receptor binding in 15 drug-naive schizophrenic patients (seven males, eight females) using (123)I-IBZM single photon emission computed tomography. Basal ganglia/frontal cortex (BG/FC) uptake ratios were obtained. No significant differences were found in global, left and right BG/FC ratios or laterality indices between males and females. No correlation was found between BG/FC ratios and age, duration of illness or scores on symptom rating scales. Our data indicate a lack of sex differences in striatal D2 receptor binding in drug-naive schizophrenic patients and do not support previous reports of left lateralized striatal asymmetry in male schizophrenic patients.

Adult↗

PubMed2004

Risperidone in the treatment of patients with delirium.

BACKGROUND: The aim of this study was to evaluate the efficacy and safety of risperidone in the treatment of patients with delirium. METHOD: We conducted a prospective, multicenter, observational 7-day study in 5 university general hospitals. Sixty-four patients (62.5% male [N = 40]; mean age: 67.3 +/- 11.4 years) hospitalized due to a medical condition who met criteria for delirium according to DSM-IV were enrolled in the study. Fifty-six patients received 7 days of treatment or less, while 8 patients continued treatment for more than 7 days. Effectiveness was assessed using the Trzepacz Delirium Rating Scale (DRS), the positive subscale of the PANSS (PANSS-P), the Mini-Mental State Examination (MMSE), and the Clinical Global Impressions scale (CGI). Safety assessment included the UKU Side Effect Rating Scale. Risperidone was administered at the time of diagnosis, and treatment was maintained according to clinical response. Response to treatment was defined as a reduction in DRS score to below 13 within the first 72 hours. Data were gathered from April to December 2000. RESULTS: Risperidone (mean dose = 2.6 +/- 1.7 mg/day at day 3) was effective in 90.6% (58/64) of the patients and significantly improved all symptoms measured by the scales from baseline to day 7 (mean scores: DRS, 22.5 +/- 4.6 at baseline to 6.8 +/- 7.0 at day 7; PANSS-P, 21.5 +/- 8.8 to 10.1 +/- 7.3; MMSE, 13.1 +/- 10.9 to 26.4 +/- 8.9; and CGI, 4.5 +/- 0.9 to 1.9 +/- 1.2) (Friedman test, p <.001 in all cases). Two patients (3.1%) experienced adverse events, but none showed extrapyramidal symptoms. CONCLUSIONS: Low-dose risperidone proved to be a safe and effective drug in the treatment of symptoms of delirium in medically hospitalized patients. These data provide the rationale for a prospective randomized controlled trial.

Aged↗

PubMed2003

Striatal dopamine D2 receptor density in neuroleptic-naive and in neuroleptic-free schizophrenic patients: an 123I-IBZM-SPECT study.

Most post-mortem autoradiographic studies have described striatal dopamine D(2) receptor up-regulation due to chronic neuroleptic exposure. The aim of our study was to compare in-vivo striatal D(2) receptor density in neuroleptic-naive and neuroleptic-free schizophrenic patients. We included 28 young (mean age: 28+/-8 years) acute psychotic patients meeting DSM-IV criteria for schizophrenia or schizophreniform disorder. Enrolled patients were either first-episode neuroleptic-naive (n=12) or neuroleptic-free (n=16) after a minimum washout period of 7 days. All neuroleptic-free subjects had previously received neuroleptic treatment for a median period of 3.5 years. Both groups were evaluated using standard clinical scales. In-vivo striatal D(2) receptor binding was assessed by basal ganglia/frontal cortex ratios using (123)I-IBZM SPECT. No statistically significant differences were found in age or clinical assessment between neuroleptic-naive and neuroleptic-free schizophrenic patients. No differences were found in the basal ganglia/frontal cortex ratios of neuroleptic-naive (1.78+/-0.11) and neuroleptic-free (1.81+/-0.15) patients. No striatal uptake laterality was observed in either group. No correlation was demonstrated between BG/FC ratios and duration of illness, period of neuroleptic exposure or time of drug washout. We conclude that our neuroleptic-naive and neuroleptic-free schizophrenic patients did not show differences in striatal D(2) receptor binding, suggesting that IBZM-SPECT fails to detect D(2) receptor up-regulation induced by chronic exposure to neuroleptic drugs.

Adult↗