Survey on schizophrenia treatment in Mexico: perception and antipsychotic prescription patterns

BACKGROUND: Since the introduction of antipsychotics, especially the so called atypicals, the treatment of schizophrenia has shown important improvements. At the present time, it is preferred to label clozapine and other antipsychotics sharing similar profiles as second-generation antipsychotics (SGAs). These medications have been proposed by some experts as a first line treatment for schizophrenia. It is critical to have reliable data about antipsychotic prescription in Mexico and to create management guidelines based on expert meetings and not only on studies carried out by the pharmaceutical industry. Only this approach will help to make the right decisions for the treatment of schizophrenia. METHODS: A translated version of Rabinowitz's survey was used to evaluate antipsychotic prescription preferences and patterns in Mexican psychiatrists. The survey questionnaire was sent by mail to 200 psychiatrists from public institutions and private practice in Mexico City and Guadalajara, Mexico. RESULTS: Recommendations for antipsychotics daily doses at different stages of the treatment of schizophrenia varied widely. Haloperidol was considered as the first choice for the treatment of positive symptoms. On the contrary, risperidone was the first option for negative symptoms. For a patient with a high susceptibility for developing extrapyramidal symptoms (EPS), risperidone was the first choice. It was also considered that SGAs had advantages over typical antipsychotics in the management of negative symptoms, cognitive impairment and fewer EPS. Besides, there was a clear tendency for prescribing typical antipsychotics at higher doses than recommended and inadequate doses for the atypical ones. CONCLUSIONS: Some of the obstacles for the prescription of SGAs include their high cost, deficient knowledge about their indications and dosage, the perception of their being less efficient for the treatment of positive symptoms and the resistance of some Mexican physicians to change their prescription pattern. It is necessary to reach a consensus, in order to establish and standardize the treatment of schizophrenia, based on the information reported in clinical trials and prevailing economic conditions in Mexico

Low muscarinic receptor binding in prefrontal cortex from subjects with schizophrenia: a study of Brodmann\u27s areas 8, 9, 10, and 46 and the effects of neuroleptic drug treatment

Objective: Aberrant cholinergic inputs and synaptic neurotransmission in the prefrontal cortex induce cognitive impairment, which is a central feature of schizophrenia. Postsynaptic excitatory muscarinic cholinergic M1 and M4 receptors are the major cholinoceptive targets in the prefrontal cortex and hence may be involved in the pathology and/or pharmacotherapeutics of schizophrenia. Method: Using quantitative autoradiography, the authors analyzed the binding of the M1/M4 receptor selective antagonist [3H]pirenzepine in prefrontal cortex (Brodmann\u27s areas 8, 9, 10, and 46) from schizophrenia patients who had (N=6) or had not (N=11) been treated with the anticholinergic agent benztropine mesylate and from normal comparison subjects (N=20). Moreover, preliminary studies of [3H]pirenzepine binding in rat frontal cortex following administration of antipsychotic drugs or benztropine mesylate were performed. Results: Relative to those of comparison subjects, the mean levels of [3H]pirenzepine binding were significantly lower in Brodmann\u27s areas 9 and 46 of the schizophrenia patients not treated with benztropine mesylate (18% lower in Brodmann\u27s area 9 and 21% lower in Brodmann\u27s area 46) and in all four examined regions of the patients who had received benztropine (51%-64% lower). Antipsychotic or anticholinergic drugs tended to increase or have no effect on the density of [3H]pirenzepine-labeled receptors in rat frontal cortex. Conclusions: Because M1 and M4 receptors are critical to the functions of prefrontal cortical acetylcholine, the present findings suggest a functional impairment in cholinergic neurotransmission in schizophrenia and the possibility that muscarinic receptors are involved in the pharmacotherapeutics of the disorder

No change in the density of the serotonin1A receptor, the serotonin4 receptor or the serotonin transporter in the dorsolateral prefrontal cortex from subjects with schizophrenia

Changes in serotonin receptors and the serotonin transporter have been reported in the dorsolateral prefrontal cortex from subjects with schizophrenia, an area of the brain thought to be important in the pathology of the illness. To further our understanding on how such changes could play a role in the pathology of the illness, in situ radioligand binding with autoradiography was used to measure the density of the serotonin1A receptor, the serotonin4 receptor and the serotonin transporter in the dorsolateral prefrontal cortex, obtained at autopsy, from 10 schizophrenic and 10 control subjects. The binding of [3H]8-OH-DPAT to serotonin1A receptor, [3H]GR113808 to the 5HT4 receptor and [3H]citalopram to serotonin transporter was not altered in subjects with schizophrenia. Significantly, only in tissue from the control subjects was there a relationship between age and the density of the serotonin4 receptor in Brodmann\u27s areas 8 (r = 0.71, P = 0.02) and 10 (r = -0.67, P = 0.03). Importantly, this confounding factor did not influence the comparison of the density of serotonin4 receptor in the tissue from the schizophrenic and control subjects. This study has failed to show a difference in the density of serotonin1A receptor, the serotonin4 receptor or the serotonin transporter in the dorsolateral prefrontal cortex (Brodmann\u27s areas 8, 9 and 10) from subjects with schizophrenia. These data suggest that not all serotonergic markers are altered in the dorsolateral prefrontal cortex from schizophrenic subjects