The ethics of the placebo in clinical practice

While discussions of the ethics of the placebo have usually dealt with their use in a research context, the authors address here the question of the placebo in clinical practice. It is argued, firstly, that the placebo can be an effective treatment. Secondly, it is demonstrated that its use does not always entail deception. Finally guidelines are presented according to which the placebo may be used for clinical purposes. It is suggested that in select cases, use of the placebo may even be morally imperative. The argument is illustrated by three case vignettes.

Association of dopaminergic and serotonergic genes with tardive dyskinesia in patients with chronic schizophrenia

Tardive dyskinesia (TD) is a long-term adverse effect of antipsychotic drugs that are dopamine D2 receptor blockers. Serotonin receptor antagonism has been proposed as a common mechanism contributing to the low extrapyramidal side effect profile of atypical antipsychotic drugs. We evaluated candidate dopamine and serotonin genes for association with drug-induced TD. We examined three polymorphisms in the dopamine D2 receptor gene (DRD2), two sites in the 3' region of the dopamine transporter (DAT) gene, two sites in the promoter and coding region of the dopamine D4 (DRD4) receptor gene, as well as polymorphic sites in the serotonin 6 receptor gene, the serotonin transporter gene and the tryptophan hydroxylase gene, for association with TD susceptibility. Schizophrenic patients with (n=59) and without TD (n=63), matched for antipsychotic drug exposure and other relevant variables, were studied. No significant associations were found. Within the limitations imposed by the size of the clinical sample, these findings suggest that the above polymorphic loci do not contribute significantly to risk for TD. Further examination of loci that yielded positive results at a trend level and investigation of other candidate genetic loci coding for antipsychotic drug targets is warranted.

Chronic high-dose glycine nutrition: effects on rat brain cell morphology

BACKGROUND

Facilitation of N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission via administration of glycine site agonists of the NMDA receptor (e.g., glycine, D-serine), and glycine transport inhibitors may represent an innovative pharmacologic strategy in schizophrenia; however, given the potential involvement of NMDA receptors in the neurotoxicity of excitatory amino acids, possible neurotoxic effects of glycinergic compounds need to be explored. Furthermore, studying brain adaptations to chronic administration of glycine site agonists may provide insights into the therapeutic mechanisms of these drugs.

METHODS

Adult rats were randomized to one of three nutritional regimens (no glycine supplementation, 1 g/kg/day, or 5 g/kg/day glycine supplementation) and to one of three treatment durations (1, 3, or 5 months). Serum glycine and serine levels at sacrifice and brain sections were examined using histologic markers of neurodegeneration (cresyl violet and silver impregnation staining) and immunohistochemical staining of glial fibrillary acidic protein, microtubule-associated protein, and neurofilament 200. To explore additional neural adaptations to high-dose glycine treatment, immunostaining was also performed for class B, N-type Ca(2+) channels.

RESULTS

Serum glycine levels increased dose dependently during glycine nutrition, whereas serine levels were not changed. In hippocampal dentate gyrus, the percentage of hypertrophied astrocytes transiently increased at 1 month. At 3 and 5 months of glycine treatment, the density of class B, N-type Ca(2+) channels was reduced in parietal cortex and hippocampus. No evidence of neuronal or glial cell excitotoxic damage or degeneration was registered at either of the treatment intervals studied.

CONCLUSIONS

These findings demonstrate for the first time that in vivo administration of high-dose glycine may induce brain morphological changes without causing neurotoxic effects. A reduction in density of class B, N-type Ca(2+) channels in specific brain regions may represent one general adaptation to long-term, high-dose glycine treatment.

Association between the serotonin 2A receptor gene and tardive dyskinesia in chronic schizophrenia

Tardive dyskinesia (TD) is a long-term adverse effect of antipsychotic drugs that are dopamine D2 receptor blockers.(1) Serotonin receptor antagonism has been proposed as a common mechanism contributing to the low extrapyramidal effects profile of atypical antipsychotic drugs.(2) We examined the association of three polymorphisms in the 5-HT2A receptor gene (HTR2A) with TD susceptibility--T102C(3) and his452tyr(4) in the coding region and A-1438G(5) in the promoter--in matched schizophrenia patients with (n = 59, SCZ-TD-Y) and without TD (n = 62, SCZ-TD-N) and normal control subjects (n = 96). The T102C and the A-1438G polymorphisms are in complete linkage disequilibrium but not his452tyr. There was a significant excess of 102C and -1438G alleles (62.7%) in the SCZ-TD-Y patients compared to SCZ-TD-N patients (41.1%) and controls (45.9%; chi(2) = 12.8, df = 2, P = 0.002; SCZ-TD-Y vs SCZ-TD-N, chi(2) = 11.4, df = 1, P = 0.0008, OR 2.41, 95% CI 1.43-3.99) and of 102CC and -1438GG genotypes (SCZ-TD-Y 42.4%, SCZ-TD-N, 16.1%, controls 20.8%, chi(2) = 13.3, df = 4, P = 0.01). The 102CC and the -1438GG genotypes were associated with significantly higher AIMS trunk dyskinesia scores (F = 3.9; df = 2, 116; P = 0.02) and more incapacitation (F = 5.0; df = 2, 115; P = 0.006). The his452tyr polymorphism showed no association with TD. These findings suggest that the 5-HT2A receptor gene is significantly associated with susceptibility to TD in patients with chronic schizophrenia. Previously reported association of the T102C and A-1438G polymorphisms with schizophrenia(6) may reflect association of a sub-group of patients with a susceptibility to abnormal involuntary movements related to antipsychotic drug exposure.

Association between the serotonin 2C receptor gene and tardive dyskinesia in chronic schizophrenia: additive contribution of 5-HT2Cser and DRD3gly alleles to susceptibility

RATIONALE

Tardive dyskinesia (TD) is a longterm adverse effect of dopamine receptor blockers. The dopamine D3 receptor gene (DRD3) ser9gly polymorphism has been previously associated with susceptibility to TD. Serotonin receptor antagonism has been proposed as a common mechanism contributing to the low extra-pyramidal effects profile of atypical antipsychotic drugs.

OBJECTIVES

To examine the association of a functional polymorphism in the 5-HT2C receptor gene (HT2CR) with TD and the joint contribution of HT2CR and DRD3 to susceptibility.

METHODS

Case control association analysis of allele and genotype frequencies among schizophrenia patients with (n=55) and without TD (n=60), matched for antipsychotic drug exposure and other relevant variables, and normal control subjects (n=97). Parametric analyses of the contribution of 5-HT2Cser and DRD3gly alleles to dyskinesia scores.

RESULTS

We found a significant excess of 5-HT2Cser alleles in schizophrenia patients with TD (27.2%) compared to patients without TD (14.6%) and normal controls (14.2%; chi2=6.4, df 2, P=0.03) which was due to the female patients (chi2=8.6, df 2, P=0.01). Among the female TD patients there was an excess of cys-ser and ser-ser genotypes (chi2= 11.9, df 4, P=0.02). Analysis of covariance (ANCOVA), controlling for age at first antipsychotic treatment, revealed a significant effect of 5-HT2C genotype on orofacial dyskinesia (OFD) scores (F=3.47, df 2, P=.03). In a stepwise multiple regression analysis, 5-HT2C and DRD3 genotype (5-HT2Cser and DRD3gly allele carriage) respectively contributed 4.2% and 4.7% to the variance in OFD scores.

CONCLUSIONS

These findings support a small but significant contribution of the HT2CR and DRD3 to susceptibility to TD, which is additive in nature.

Treatment-resistant schizophrenia and staff rejection

This study examined the relationship between characteristics of patients suffering from treatment-refractory schizophrenia and staff rejection and criticism. Subjects were 30 inpatients with treatment-resistant schizophrenia and the 29 staff members treating them. Measures included assessment of the patients' symptoms and aggression risk profile using the Positive and Negative Syndrome Scale (PANSS) and assessment of staff attitudes toward these patients using the Patient Rejection Scale (PRS). Nursing staff completed the Nurses' Observation Scale for Inpatient Evaluation (NOSIE). PRS ratings did not correlate with patients' demographic and treatment characteristics. Significant correlations existed, however, between increased staff rejection and higher scores for PANSS cognitive factor and NOSIE manifest psychosis factor. Negative symptoms, although preponderant in the patient sample, were not significant predictors of staff rejection on the PRS. Older nursing staff tended to view patients as more irritable and manifestly psychotic. These findings suggest that disorganized behavior and impaired cognition dysfunction areas are more likely to be associated with high levels of rejection among staff working with treatment-resistant schizophrenia patients. Incorporation of the relatively new concepts of cognitive dysfunction and treatment resistance in staff training programs and multidisciplinary team reviews may greatly benefit schizophrenia patients and the staff treating them.

Genotypic association between the dopamine D3 receptor and tardive dyskinesia in chronic schizophrenia

Dopamine receptor antagonism is a common mechanism underlying the therapeutic efficacy of all classical antipsychotic drugs. It is also thought to underlie the propensity of these agents to induce the movement disorder, tardive dyskinesia (TD), in one fifth of chronically exposed schizophrenia patients. We examined the polymorphic serine to glycine substitution in the first exon of the gene encoding the dopamine D3 receptor (DRD3) inn 53 schizophrenia patients with TD, 63 matched patients with similar antipsychotic exposure but no TD and 117 normal controls. There was a difference in allele frequency that was of borderline significance (P = 0.055), due to an excess of the DRD3gly allele (allele 2) in the schizophrenia patients with TD. The difference in genotype distribution among the groups was highly significant (chi2 = 19.1, d.f. 4, P = 0.0008) due to an excess of the DRD3ser-gly genotype in the schizophrenia patients with TD. The difference between the schizophrenia patients with TD and the controls was highly significant (chi2 = 19.0, d.f. 2, P = 0.00007), even after correction for multiple testing, as was the difference between the combined group of schizophrenia patients and the controls (chi2 = 12.2, d.f. 2, P = 0.002). Comparing the schizophrenia patients with and without TD, genotypes containing the gly allele (DRD3ser-gly and DRD3gly-gly genotypes combined) were significantly associated with dyskinesia (OR = 2.62, 95% CI 1.18-5.59, P = 0.02). DRD3 genotype and age at first antipsychotic treatment contributed significantly to total score on the Abnormal Involuntary Movements Scale (AIMS). The contribution of DRD3 to the variance in AIMS total was 5.2% and the total proportion of the variance accounted for by these two variables together was 11.9%. These results support and extend the report by Steen et al (1997) of an association between DRD3 and TD in schizophrenia patients.

Environment and vulnerability to major psychiatric illness: a case control study of early parental loss in major depression, bipolar disorder and schizophrenia

The current focus on identifying genes which predispose to psychiatric illness sharpens the need to identify environmental factors which interact with genetic predisposition and thus contribute to the multifactorial causation of these disorders. One such factor may be early parental loss (EPL). The putative relationship between early environmental stressors such as parental loss and psychopathology in adult life has intrigued psychiatrists for most of this century. We report a case control study in which rates of EPL, due to parental death or permanent separation before the age of 17 years were evaluated in patients with major depression (MD), bipolar disorder (BPD) and schizophrenia (SCZ), compared to individually matched, healthy control subjects (MD-Control, 79 pairs; BPD-Control, 79 pairs; SCZ-Control, 76 pairs). Loss of parent during childhood significantly increased the likelihood of developing MD during adult life (OR=3.8, P=0.001). The effect of loss due to permanent separation (P=0.008) was more striking than loss due to death, as was loss before the age of 9 years (OR=11.0, P=0.003) compared to later childhood and adolescence. The overall rate of EPL was also increased in BPD (OR=2.6, P=0.048) but there were no significant findings in any of the subcategories of loss. A significantly increased rate of EPL was observed in schizophrenia patients (OR=3.8, P=0.01), particularly before the age of 9 years (OR=4.3, P=0.01). Comparison of psychosocial, medical and clinical characteristics of subjects with and without a history of EPL, within the larger patient groups from which the matched samples were drawn (MD, n=136; BPD, n=107; SCZ, n=160), yielded few significant findings. Among the controls (n=170), however, subjects who had experienced EPL, reported lower incomes, had been divorced more frequently, were more likely to be living alone, were more likely to smoke or have smoked cigarettes and reported more physical illness (P=0.03-0.001). Long term neurobiological consequences of early environmental stressors such as maternal deprivation have been extensively studied in many animal species. Recently, enduring changes in hypothalamic-pituitary-adrenal axis function, including corticotrophin releasing factor gene expression, have received particular attention. Analogous processes may be implicated in the effect of EPL on human vulnerability to psychopathology, via alterations in responsiveness to stress. Genetic predisposition may influence the degree of susceptibility of the individual to the effects of early environmental stress and may also determine the psychopathological entity to which the individual is rendered vulnerable as a consequence of the stress.

High dose glycine nutrition affects glial cell morphology in rat hippocampus and cerebellum

Enhancement of N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission by glycine (Gly) administration may represent a novel pharmacological strategy in schizophrenia. Given the involvement of NMDA receptors in plasticity and excitatory processes, the present study explores effects of Gly on brain cell morphology. Adult rats were randomized to receive, for 2 wk, no dietary supplementation or supplementation with 0.8 or 3.2 g/kg per day Gly. Glial cell morphology was examined using antibodies to glial fibrillary acidic protein (GFAP) and to microglial complement receptor 3 (CR3). Cresyl violet was used for general cellular staining. No evidence of neuronal or microglial pathology was found. Although astrocyte proliferation was not evident in Gly-treated rats, GFAP-like immunoreactivity was dose-dependently increased in the hippocampus (p<0.01), whereas in cerebellum, a dose dependent decrease in density of astocytic fibres was demonstrated (p<0.01). These findings demonstrate for the first time that in vivo administration of high dose Gly may induce brain morphology changes.

Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia

BACKGROUND

Disturbances of N-methyl-D-aspartate (NMDA) receptor-mediated glutamatergic neurotransmission may play an important role in the pathophysiology of negative symptoms of schizophrenia. Glycine, a small nonessential amino acid, functions as an obligatory coagonist at NMDA receptors through its action at a strychnine-insensitive binding site on the NMDA receptor complex. Glycine-induced augmentation of NMDA receptor-mediated neurotransmission may thus offer a potentially safe and feasible approach for ameliorating persistent negative symptoms of schizophrenia.

METHODS

Twenty-two treatment-resistant schizophrenic patients participated in a double-blind, placebo-controlled, 6-week, crossover treatment trial with 0.8 g/kg per day of glycine added to their ongoing antipsychotic medication. Clinical assessments, including the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS), the Simpson-Angus Scale for Extrapyramidal Symptoms, and the Abnormal Involuntary Movement Scale, were performed biweekly throughout the study. Clinical laboratory values and amino acid serum levels were monitored.

RESULTS

Glycine treatment was well tolerated and induced increased glycine (P=.001) and serine (P=.001) serum levels. Glycine administration resulted in (1) a significant (P<.001) 30%+/-16% reduction in negative symptoms, as measured by the PANSS, and (2) a significant (P<.001) 30%+/-18% improvement in the BPRS total scores. The improvement in negative symptoms was unrelated to alterations in extrapyramidal effects or symptoms of depression. Low pretreatment glycine serum levels significantly predicted (r= 0.80) clinical response.

CONCLUSION

These findings support hypoglutamatergic hypotheses of schizophrenia and suggest a novel approach for the pharmacotherapy of negative symptoms associated with this illness.

Risperidone-induced rabbit syndrome: an unusual movement disorder caused by an atypical antipsychotic

Rabbit syndrome is a rare side effect of chronic neuroleptic administration characterized by rapid, fine, rhythmic movements of the mouth along a vertical axis. It gains its name from an unusual resemblance to the chewing and puckering motions of the rabbit. It is generally thought to be an extra-pyramidal side effect, in part due to its rapid response to anti-cholinergic medication. This is the first case report of risperidone, an atypical antipsychotic, inducing the syndrome. The theoretical implications for the classification of the syndrome along the spectrum of neuroleptic-induced movement disorders are discussed.

The role of N-methyl-D-aspartate (NMDA) receptor-mediated neurotransmission in the pathophysiology and therapeutics of psychiatric syndromes

The study of excitatory amino acids (EAAs) has recently resulted in new and fundamental concepts in neuroscience. This progress has led to a growing awareness of the crucial role that brain EAAs systems play in a variety of physiological and pathological processes. The N-methyl-D-aspartate (NMDA) receptor, presently the most well understood subtype of EAAs receptors, has been implicated in crucial physiological processes such as synaptogenesis, learning and memory. Dysfunctions of NMDA receptors seem to play a crucial role in the neurobiology of disorders such as Parkinson's disease, Alzheimer's disease, epilepsy and ischemic stroke. This paper is a review of emerging data indicating that alterations of NMDA receptor function may be pivotal to the pathophysiology of four common psychiatric syndromes: schizophrenia, major depression, posttraumatic stress disorder, and alcoholism. Special emphasis is placed on the current state of development of pharmacological strategies aiming at the modulation of NMDA receptor-mediated neurotransmission in these disorders.

Serum neuroleptic levels during reduced dose fluphenazine decanoate maintenance therapy

Forty-one remitted and chronically psychotic schizophrenic out-patients completed a two-year clinical trial during which they were assigned, on the basis of their clinically determined maintenance dosages, to one of two reduced, fixed-dose fluphenazine decanoate (FD) regimens: 35 mg/4 wks (19 patients) or 10 mg/4 wks (22 patients). Eighty-one percent of chronically psychotic patients, who represented 74% of the high dose group, relapsed, in comparison with only 38% of remitted patients (p < .001), who represented 86% of the low dose group. During this study serum neuroleptic levels were assessed, using the radioreceptor assay, before the administration of each FD injection and whenever a patient relapsed. Overall, 334 serum neuroleptic activity measurements were performed. Serum neuroleptic levels were detectable in all patients and were higher, although not significantly, in the 35 mg/4 wks group. The dichotomous clinical outcome of chronically psychotic and remitted patients occurred within the framework of essentially similar serum neuroleptic levels. These findings suggest that: 1) serum neuroleptic levels can be monitored during low dose FD treatment, 2) the poor maintenance therapy outcome of chronically psychotic patients cannot be accounted for by inadequate neuroleptic bioavailability, 3) a majority of remitted FD maintained patients retain their clinical response at serum neuroleptic levels lower than those initially attained at steady state.

Schizophrenia, chronic hospitalization and the 5-HT2C receptor gene

Frequency of a polymorphism in the coding region of the 5-hydroxytryptamine2C (5-HT2C) receptor gene (HTR2C Xq24) was not significantly different in 122 unrelated Israeli schizophrenia patients compared with 180 control subjects matched for gender and ethnicity. However, proportion of time spent in hospital since the first admission was significantly greater in patients hemi- of homozygous for the 5-HT2Cser allele than in patients carrying other genotypes (p = 0.006). The 5-HT2Cser genotype conferred a 3.3-fold increased risk for lifetime hospitalization exceeding 10 years. Genetically determined variation in the 5-HT2C receptor may influence the clinical course and phenotypic expression of schizophrenia.

Dopamine D4 receptor gene polymorphisms: relation to ethnicity, no association with schizophrenia and response to clozapine in Israeli subjects

The dopamine D4 receptor (DRD4) is a candidate gene in the search for a genetic etiology of schizophrenia and for pharmacogenetic factors in the response to antipsychotic treatment. Previous work has not found linkage or association of a polymorphism in exon 3 of this gene with diagnosis of schizophrenia or response to clozapine. In this study we examined this association in Israeli schizophrenic subjects treated with clozapine, compared to ethnically matched controls. Another polymorphism of this gene, in exon 1, was also studied. Both polymorphisms showed no association with schizophrenia or treatment response. A significant difference in allelic distribution of DRD/ exon 3 polymorphism was found between Ashkenazi and non-Ashkenazi control subjects.

Double-blind, placebo-controlled, crossover trial of glycine adjuvant therapy for treatment-resistant schizophrenia

BACKGROUND

It has been proposed that schizophrenia is associated with underactivity of brain glutamatergic neurotransmission, especially at the level of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor. Glycine potentiates NMDA receptor-mediated neurotransmission, indicating that it may serve as an effective therapeutic agent in the treatment of schizophrenia.

METHOD

Eleven treatment-resistant patients with chronic schizophrenia completed a double-blind, placebo-controlled, six-week, randomly assigned, crossover treatment trial of 0.8 g/kg body weight/day of glycine, added to their prior antipsychotic treatment.

RESULTS

Glycine was well tolerated, resulted in significantly increased serum glycine levels and induced a mean 36 (7%) reduction in negative symptoms (P < 0.0001). Significant improvements were also induced in depressive and cognitive symptoms. The greatest reduction in negative symptoms was registered in the patients who had the lowest baseline serum glycine levels.

CONCLUSIONS

These results extend previous findings and suggest an additional approach to the pharmacotherapy of negative symptoms and cognitive deficits in schizophrenia.

Amelioration of negative symptoms in schizophrenia by glycine

Phencyclidine induces a psychotomimetic state by blocking neurotransmission at N-methyl-D-aspartic acid (NMDA) receptors. In a double-blind, placebo-controlled fashion, 14 medicated patients with chronic schizophrenia were treated with glycine, a potentiator of NMDA-receptor-mediated neurotransmission. Significant improvement in negative symptoms occurred in the group given glycine but not in the group given placebo, suggesting that potentiation of NMDA-receptor-mediated neurotransmission may represent an effective treatment for neuroleptic-resistant negative symptoms in schizophrenia.

Trial of maintenance neuroleptic dose reduction in schizophrenic outpatients: two-year outcome

BACKGROUND

An open trial was undertaken to assess the feasibility of reducing maintenance doses in a public clinical setting and to identify eventual predictors of outcome after dose reduction in schizophrenia.

METHOD

Forty-one remitted and chronically psychotic schizophrenic outpatients were assigned, on the basis of their previously clinically determined maintenance dosages, to one of two reduced fluphenazine decanoate regimens: 35 mg/4 wk (19 patients) or 10 mg/4 wk (22 patients). Subsequently, patients were assessed, for a 2-year period, by means of the Brief Psychiatric Rating Scale, the Scale for the Assessment of Positive Symptoms, the Scale for the Assessment of Negative Symptoms, the Simpson-Angus Scale, and the Abnormal Involuntary Movement Scale.

RESULTS

Chronically psychotic patients, who represented 74% of the high-dose group and only 14% of the low-dose group, had a significantly higher cumulative relapse rate (81%) than remitted patients (38%). For most remitted patients a dose of 10 mg of fluphenazine decanoate, injected every 4 weeks, was satisfactory. Both remitted and chronically psychotic patients displayed reductions in the severity of neuroleptic side effects.

CONCLUSION

Maintenance dose reductions may be beneficial for many schizophrenic outpatients. Chronically psychotic and remitted patients maintained on lowered dosages differ significantly in the stability of their course of illness.

The Patient Rejection Scale in an Israeli sample: correlations with relapse and physician's assessment

The Patient Rejection Scale (PRS), which was developed to assess the feelings of rejection that relatives experience toward mental patients, was administered to a sample of 50 family members living with schizophrenic outpatients in Jerusalem, Israel. PRS response distribution was similar to that reported for a New York City sample. Total rejection scores were significantly correlated with a number of demographic variables and with the treating physician's assessment of the degree of rejection, hostility and criticism of the respective family members. Physician's rating of emotional over-involvement did not correlate with PRS scores. Both PRS and treating physician's ratings correlated significantly with course of illness parameters. The findings and their implications are discussed in the context of expressed emotion (EE) research.