Schizophrenic patients treated with high dose phenothiazine or thioxanthene become deficient in polyunsaturated fatty acids in their thrombocytes

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia and is reputed to have a low level of extrapyramidal adverse effects. As far as we are aware, its use is limited to Germany, Poland, the former Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia or related psychoses in comparison with placebo, no treatment or other antipsychotic medications.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register, which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile. We searched the references of all included studies for further trials. We contacted pharmaceutical companies and authors of trials. We updated this search on 16th July 2012.

SELECTION CRITERIA

We selected all randomised controlled trials that compared perazine with other treatments for people with schizophrenia or schizophrenia-like psychoses, or both.

DATA COLLECTION AND ANALYSIS

The review authors (SL, BH, BHe) independently inspected the citations and where possible abstracts and ordered papers for re-inspection and quality assessment. We independently extracted data. We calculated the risk ratio (RR) and 95% confidence interval (CI) using a random-effects model. For continuous data, we calculated mean differences (MD). We inspected all data for heterogeneity, assessed trials for risk of bias and created summary of findings tables using GRADE.

MAIN RESULTS

The review now includes seven trials with a total of 479 participants. In only one trial, with 95 participants, perazine appeared superior to 'active placebo' (trimipramine) at five weeks for the outcome of 'no important global improvement' (n = 95, RR 0.43 CI 0.2 to 0.8, low quality evidence), but there was no statistically significant difference in most measures of mental state. Perazine did not induce more general adverse events than placebo but more participants received at least one dose of antiparkinson medication (n = 95, RR 4.50 CI 1.0 to 19.5, very low quality evidence).Six small trials comparing perazine with other antipsychotics, including 384 participants in total, were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible on most occasions. In the six studies, a similar number of participants receiving perazine or comparator antipsychotics (amisulpride, haloperidol, olanzapine, ziprasidone, zotepine) left the studies early (n = 384, RR 0.97 CI 0.68 to 1.38, low quality evidence). The results on efficacy could not be meta-analysed because the authors presented their results in very different ways. No obvious differences in adverse events between perazine and other antipsychotics could be derived from the limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a way that was suitable for use in meta-analysis, but three small comparisons with the second-generation antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n = 111, RR 0.31 CI 0.1 to 1.1), dyskinesia (n = 111, RR 0.47 CI 0.1 to 3.5), parkinsonism (n = 81, RR 1.21 CI 0.5 2.8) or tremor (n = 40, RR 0.80 CI 0.3 to 2.6) with perazine.

AUTHORS' CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials are insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics but this is based on small comparisons. This should be clarified in larger, well-designed trials.

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia and is reputed to have a low level of extrapyramidal adverse effects. As far as we are aware, its use is limited to Germany, Poland, the former Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia, and schizophrenia-like psychoses.

SEARCH STRATEGY

We searched the Cochrane Schizophrenia Group's register which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile (last update of the review March 2005). We searched references of all included studies for further trials. We contacted pharmaceutical companies and authors of trials.

SELECTION CRITERIA

We selected all randomised controlled trials that compared perazine with other treatments for people with schizophrenia and/or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

We independently (SL, BH) inspected citations and where possible abstracts and ordered papers for re-inspection and quality assessment. We independently extracted data. We excluded data if loss to follow up was greater than 50%. For homogeneous dichotomous data we calculated the Relative Risk (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) on an intention-to-treat basis. For continuous data, we calculated weighted mean differences (WMD). We inspected all data for heterogeneity.

MAIN RESULTS

We included six trials with a total of 288 participants. In only one trial with 95 participants, perazine appeared superior to 'active placebo' (trimipramine) at five weeks for the outcome of 'no important global improvement' (n=95, RR 0.43 CI 0.2 to 0.8, NNT 4 CI 2 to 13), but there was no statistically significant difference in most measures of mental state. Perazine did not induce more general adverse events than placebo, but more participants received at least one dose of antiparkinson medication (n=95, RR 4.50 CI 1.0 to 19.5, NNH 6 CI 4 to 33). Five small trials comparing perazine with other antipsychotics, including in total only 193 participants, were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible in most occasions. A similar number of participants receiving perazine or comparator antipsychotics left the studies early (n=193, RR 0.85, CI 0.5 to 1.4). The results on efficacy were controversial and need further assessment by randomised controlled trials. No obvious differences in adverse events between perazine and other antipsychotics could be derived from the limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a suitable way for use in meta-analysis, but three small comparisons with the atypical antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n=111, RR 0.31 CI 0.1 to 1.1), dyskinesia (n=111, RR 0.47 CI 0.1 to 3.5), parkinsonism (n=81, RR 1.21 CI 0.5 2.8) or tremor (n=40, RR 0.80 CI 0.3 to 2.6) with perazine.

AUTHORS' CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials is insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics, and this should be clarified in larger, well-designed trials.

Polyunsaturated fatty acid levels in red cell membranes of unmedicated schizophrenic patients

There are several reports of reduced levels of polyunsaturated fatty acids (PUFA), particularly arachidonic acid (AA) and docosahexaenoic acid (DHA), in membrane phospholipid from various tissues including red blood cells (RBC) taken from schizophrenic patients. However, reports have not been entirely consistent and most studies have been confounded by the potential effects of environmental factors including antipsychotic medication and diet. We measured PUFA levels in RBC from two separate groups of unmedicated patients and control subjects from India and Malaysia, populations which have substantial differences in diet. We found no significant difference in levels of AA between patients and control subjects in either population. Levels of adrenic acid were significantly reduced, and levels of DHA significantly increased in both clinical populations. However, diet-related differences in DHA between the populations from India and Malaysia were much greater than differences between schizophrenic patients and controls. It is concluded that reduced RBC membrane levels of AA and DHA are not pathognomic of schizophrenia but that variations in cell membrane fatty acid levels are an epiphenomenon which may reflect underlying abnormalities of phospholipid and fatty acid metabolism and their interaction with environmental factors including medication and diet.

On the relationship between methylnicotinate-induced skin flush and fatty acids levels in acute psychosis

Vasodilation induced by methylnicotinate, a fatty acid- and cyclooxygenase-dependent process, is reduced or absent in patients with schizophrenia. This phenomenon has been suggested to be useful as a diagnostic test for the illness. To determine whether reduced flushing is specific to schizophrenia and is caused by a deficiency in membrane fatty acids, the extent of topically applied methylnicotinate-induced vasodilation was measured in 23 subjects with schizophrenia, 20 subjects with bipolar disorder and 34 healthy volunteers along with red cell fatty acid concentrations and measures of clinical severity. Although there was a significant decrease in an estimate of vasodilation (erythema) compared with healthy volunteers in both schizophrenia and bipolar groups, the schizophrenia group responded significantly less than subjects with bipolar disorder. The reduction in the bipolar group was partly due to a delayed vasodilatory reaction, an effect not observed in subjects with schizophrenia. In subjects with schizophrenia, there were no significant correlations between methylnicotinate response and fatty acid concentrations. The authors conclude that the methylnicotinate procedure can differentiate schizophrenia from other serious mental illness. The methylnicotinate insensitivity in schizophrenia, however, is likely to be due to a deficiency in the fatty acid precursors required for the vasodilatory reaction.

Perazine for schizophrenia

BACKGROUND

Perazine is an old phenothiazine derivative used for the treatment of people with schizophrenia which has a reputed low level of extrapyramidal side-effects. However, its use is restricted in the sense that - to the best knowledge of the reviewers - it is only marketed in Germany, Poland, Yugoslavia and the Netherlands.

OBJECTIVES

To examine the effects of perazine for those with schizophrenia, and schizophrenia-like psychoses.

SEARCH STRATEGY

Electronic searches of the Cochrane Schizophrenia Group's register which includes relevant randomised controlled trials from the bibliographic databases Biological Abstracts, CINAHL, The Cochrane Library, EMBASE, MEDLINE, PsycLIT, LILACS, PSYNDEX, Sociological Abstracts and Sociofile were undertaken. References of all included studies were searched for further trials. Pharmaceutical companies and authors of trials were contacted.

SELECTION CRITERIA

All randomised controlled trials that compared perazine with other treatments for people with schizophrenia and/or schizophrenia-like psychoses.

DATA COLLECTION AND ANALYSIS

Citations and, where possible, abstracts were independently inspected by two reviewers, papers ordered, re-inspected and quality assessed. Data were independently extracted. Data were excluded if loss to follow up was greater than 50%. For homogeneous dichotomous data the Relative Risk (RR), 95% confidence interval (CI) and, where appropriate, the number needed to treat (NNT) were calculated on an intention-to-treat basis. For continuous data, weighted mean differences were calculated (WMD). All data were inspected for heterogeneity.

MAIN RESULTS

Six trials with a total of 288 participants are included. According to only one trial with 95 participants perazine appeared superior to active placebo (trimipramine) at five weeks for the outcome of 'no important global improvement' (n=95, RR 0.6, CI 0.3-0.9, NNT 4, CI 2-17), but there was no difference in various measures of mental state. The side-effect risk of perazine compared to placebo could not be estimated because they were not reported. Five small trials including only 193 participants which compared perazine with other antipsychotics were incompletely reported and the outcomes were presented in various ways so that meta-analysis was not possible in most occasions. A similar number of participants receiving perazine or comparator antipsychotics left the studies early (n=193, RR 0.9, CI 0.5-1.4). The results on efficacy were controversial and need further assessment by randomised controlled trials. No obvious differences in adverse events between perazine and other antipsychotics could be derived from these limited data. Two haloperidol comparisons did not present extrapyramidal side-effects in a way usable for meta-analysis, but three small comparisons with the atypical antipsychotics zotepine and amisulpride showed no higher risk of akathisia (n=111, RR 0.3, CI 0.1-1.1), dyskinesia (n=111, RR 0.5, CI 0.1-3.5), parkinsonism (n=81, RR 1.2, CI 0.5-2.8) or tremor (n=40, RR 0.8, CI 0.3-2.3) with perazine.

REVIEWER'S CONCLUSIONS

The number, size and reporting of randomised controlled perazine trials is insufficient to present firm conclusions about the properties of this antipsychotic. It is possible that perazine is associated with a similar risk of extrapyramidal side-effects as some atypical antipsychotics, and this should be clarified in larger, well-designed trials.

Essential fatty acids, lipid membrane abnormalities, and the diagnosis and treatment of schizophrenia

Recent research suggests that deficient uptake or excessive breakdown of membrane phospholipids may be associated with schizophrenia. We review available clinical research on abnormalities in membrane fatty acid composition and metabolism in schizophrenia, and therapeutic trials of fatty acid in this disorder. All potentially relevant English-language articles were identified from the medical and psychiatric literature with the aid of computer searches using key words such as lipids, phospholipids, prostaglandins and schizophrenia. All studies which include human subjects are reviewed. Empirical studies related to membrane hypotheses of schizophrenia focus on: 1) assessment of prostaglandins (PG) and their essential fatty acid (EFA) precursors in the tissues of patients with schizophrenia; 2) evaluation of the niacin flush test as a possible diagnostic marker; 3) evaluation of phospholipase enzyme activity; 4) NMR spectroscopy studies of brain phospholipid metabolism; and 5) therapeutic trials of PG precursors for the treatment of schizophrenia. The most consistent clinical findings include red blood cell fatty acid membrane abnormalities, NMR spectroscopy evidence of increased phospholipid turnover and a therapeutic effect of omega-3 fatty acid supplementation of neuroleptic treatment in some schizophrenia patients. Studies of EFA metabolism have proved fruitful for generating and testing novel etiologic hypotheses and new therapeutic agents for schizophrenia. Greater attention to factors that influence tissue EFA levels such as diet, tobacco and alcohol are required to reconcile inconsistent findings. Treatment studies, although promising, require independent replication.

Red cell membrane fatty acids, cytosolic phospholipase-A2 and schizophrenia

Forty subjects with schizophrenia and 40 age- and sex-matched controls were recruited, and blood samples were obtained for analysis of red cell membrane fatty acid composition by capillary gas chromatography. A blood sample was also taken from the same population to test for allelic association between schizophrenia and a polymorphism close to the promoter site of the cytosolic phospholipase-A2 gene which is mapped to chromosome 1q25. The schizophrenic population was heterogeneous with regards age, symptoms severity and treatment. A significantly higher percentage concentration of dihomogamma-linolenic acid (DGLA) was found in the red cell membranes of schizophrenics compared to matched controls. All other fatty acids examined showed no difference from the normal population. No correlation was found between any demographic factor, treatment variable, diet, drug use, alcohol or tobacco consumption which could explain the biochemical findings. A negative correlation was found between the concentration of DGLA in red blood cell (RBC) membranes and severity of symptoms of schizophrenia. In particular, there was a significant correlation (r = -0.41, p = 0.009) between DGLA percentage concentrations and 'disorganised' symptoms. No association was found between schizophrenia and alleles of the polymorphism near the phospholipase-A2 gene or between fatty acid concentrations and the presence of any particular alleles. This study therefore finds support for membrane phospholipid abnormalities in patients with schizophrenia and particular symptom clusters, but does not replicate a previous report of an allelic association between a polymorphism close to the site of the cytosolic phospholipase-A2 gene and schizophrenia.

On the molecular etiology of decreased arachidonic (20:4n-6), docosapentaenoic (22:5n-6) and docosahexaenoic (22:6n-3) acids in Zellweger syndrome and other peroxisomal disorders

Alterations in the metabolism of arachidonic (20:4n-6), docosapentaenoic (22:5n-6), and docosahexaenoic (22:6n-3) acids and other polyunsaturated fatty acids in Zellweger syndrome and other peroxisomal disorders are reviewed. Previous proposals that peroxisomes are necessary for the synthesis of 22:6n-3 and 22:5n-6 are critically examined. The data suggest that 22:6n-3 is biosynthesized in mitochondria via a channelled carnitine-dependent pathway involving an n-3-specific delta-4 desaturase, while 20:4n-6, 20:5n-3 and 22:5n-6 are synthesized by both mitochondrial and microsomal systems; these pathways are postulated to be interregulated as compensatory-redundant systems. Present evidence suggests that 22:6n-3-containing phospholipids may be required for the biochemical events involved in successful neuronal migration and developmental morphogenesis, and as structural cofactors for the functional assembly and integration of a variety of membrane enzymes, receptors, and other proteins in peroxisomes and other subcellular organelles. A defect in the mitochondrial desaturation pathway is proposed to be a primary etiologic factor in the clinicopathology of Zellweger syndrome and other related disorders. Several implications of this proposal are examined relating to effects of pharmacological agents which appear to inhibit steps in this pathway, such as some hypolipidemics (fibrates), neuroleptics (phenothiazines and phenytoin) and prenatal alcohol exposure.

Essential fatty acid deficiency in erythrocyte membranes from chronic schizophrenic patients, and the clinical effects of dietary supplementation

There is now convincing evidence that membrane phospholipid metabolism is abnormal in schizophrenic patients. Our own studies, consistent with those of other research groups, have shown marked depletion of essential fatty acids, particularly arachidonic acid and docosahexanoic acid, in red blood cell membranes from schizophrenic patients relative to healthy control subjects. We also present preliminary evidence that similar abnormalities are present in first degree relatives of schizophrenic patients. Furthermore, it appears that changes in diet, which modify membrane levels of fatty acids, can have significant effects upon symptoms of schizophrenia and tardive dyskinesia (TD). Thus, we have found that schizophrenic patients who eat more (n-3) fatty acids in their normal diet have less severe symptoms. In a pilot study of (n-3) fatty acid supplementation we observed significant improvement in both schizophrenic symptoms and tardive dyskinesia over a 6 week period.

Reduced susceptibility to oxidative damage of erythrocyte membranes from medicated schizophrenic patients

Susceptibility to non-enzymatic peroxidation of erythrocyte membranes from medicated schizophrenic patients relative to healthy control subjects was investigated by measuring internalization into erythrocytes of ethylene glycol, cellobiotol or mannitol, with or without preincubation with cumene hydroperoxide or with chlorpromazine. The main finding was that erythrocytes from schizophrenic patients were less susceptible than those from control subjects to non-enzymatic oxidative damage from cumene hydroperoxide, as measured by internalization of cellobiotol and mannitol. At baseline before incubation, there was reduced internalization of cellobiotol and mannitol and this was reduced even further by preincubation with chlorpromazine. It is suggested that previous findings of fatty acid deficits in erythrocyte membranes from neuroleptic-treated schizophrenic patients are unlikely to have resulted from non-enzymatic oxidative damage of the membrane. Furthermore, it is suggested that depleted erythrocyte membrane essential fatty acids are more likely to be the result of the schizophrenic process rather than antipsychotic drug treatment, and that antipsychotic drugs may even offer protection against membrane lipid peroxidation.

Acute non-lymphoblast leukaemia presenting as a Guillain-Barré syndrome

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