Clinical challenges in the psychopharmacology of schizophrenia

Better pharmacological treatments for schizophrenia have elevated the expectations of patients and families and allow a wider range of therapeutic options for clinicians. At the same time, the treatment of schizophrenia has become more complex, and clinical decisions must often be made in the absence of unambiguous empirical guidelines. Under these circumstances, good patient care is based on clinical judgement informed by available clinical research. This issue of the Schizophrenia Bulletin reviews research in areas that represent major clinical challenges in the psychopharmacology of schizophrenia.

Controlled, dose-response study of sertindole and haloperidol in the treatment of schizophrenia. Sertindole Study Group

OBJECTIVE

This multicenter, double-blind, placebo-controlled study evaluated the efficacy and safety of three doses of sertindole (12, 20, and 24 mg/day) and haloperidol (4, 8, and 16 mg/day) in the treatment of psychotic symptoms for 497 hospitalized patients with schizophrenia.

METHOD

The patients were randomly assigned to one of the medication groups and received treatment for 8 weeks. Changes in Positive and Negative Syndrome Scale, Scale for the Assessment of Negative Symptoms, Brief Psychiatric Rating Scale, and Clinical Global Impression scores were used as evaluations of treatment efficacy. Three rating scales were used to assess extrapyramidal symptoms as well as the occurrence of adverse events and the use of medications related to extrapyramidal symptoms.

RESULTS

Both sertindole and haloperidol were comparably effective in the treatment of psychosis, and all dose levels were significantly more effective than placebo. For the treatment of negative symptoms, only sertindole, 20 mg/day, was significantly more effective than placebo. For all extrapyramidal symptom measures, sertindole was clinically and statistically indistinguishable from placebo, and rates of extrapyramidal symptoms were not dose related. All dose levels of haloperidol produced significantly more extrapyramidal symptoms than placebo or sertindole. Adverse events associated with sertindole treatment were mild in severity.

CONCLUSIONS

Sertindole is a new antipsychotic agent effective for the treatment of both the positive and negative symptoms of schizophrenia, with motor side effects that are indistinguishable from those associated with placebo.

What are the therapeutic needs in schizophrenia and how are they satisfied by new antipsychotics?

Although considerable progress has been made in the management of schizophrenia, much remains to be achieved in meeting the therapeutic needs of patients with this illness. Conventional antipsychotics have revolutionized treatment, but a substantial proportion of patients derive inadequate benefit and many suffer from adverse effects. Compliance with medication remains an enormous problem. With a number of new drugs soon to be available, it is hoped that valuable alternatives can be provided, increasing the possibility of good therapeutic response and increasing the benefit-to-risk ratio.

Relapse and rehospitalization during maintenance treatment of schizophrenia. The effects of dose reduction and family treatment

BACKGROUND

Previous studies have examined dose reduction and family treatment in schizophrenia, but none has examined their interaction. This study assessed the impact of dose reduction of antipsychotic medication and family treatment on relapse and rehospitalization during maintenance treatment.

METHODS

Subjects were 313 male and female outpatients at 5 centers with a DSM-III-R diagnosis of schizophrenia or schizoaffective disorder. In a 3 x 2 design, subjects were randomized to 1 of 3 medication strategies using fluphenazine decanoate under double-blind conditions: continuous moderate dose (standard) (12.5-50 mg every 2 weeks); continuous low dose (2.5-10 mg every 2 weeks); or targeted, early intervention (fluphenazine only when symptomatic). Subjects also were randomized to 1 of 2 family treatment strategies (supportive or applied). Supportive family management involved monthly group meetings. The more intensive applied family management involved monthly group meetings and home visits where communication and problem-solving skills were taught. Patients and families were treated and assessed for 2 years.

RESULTS

Both continuous low-dose and targeted treatment increased use of rescue medication and relapse; only targeted treatment increased rehospitalization. This pattern was consistent across both family treatments; there were no differences between family treatments.

CONCLUSIONS

These findings reaffirm the value of antipsychotic medication in preventing relapse and rehospitalization. The absence of family treatment differences may be because both conditions engaged families.

Chronic hepatitis C virus infection in humans: induction of hepatic nitric oxide synthase and proposed mechanisms for carcinogenesis

Chronic inflammatory states frequently lead to the increased production of nitric oxide (NO) via inducible NO synthase (NOS-2). In addition, NO may produce mutagenesis through several mechanisms such as DNA oxidation, DNA deamination, and the formation of N-nitroso compounds. As there is a strong association between human hepatitis C virus (HCV) infection and the development of hepatocellular carcinoma (HCC), we were interested in whether human HCV hepatitis leads to induction of NOS-2 and if the mutation repair system of p53/p21 was upregulated. Reverse transcriptase-polymerase chain reaction (RT-PCR) for human NOS-2 message was performed on RNA samples from both liver biopsies and whole liver from HCV-positive and control patients (normal liver from hepatic resections for metastases). Immunohistochemistry (IHC) for p53 and Western blot analysis for p21 were also performed on the whole liver samples. From the liver biopsies, 60% of HCV-positive patients expressed NOS-2 by RT-PCR. Looking at the whole liver samples, 100% of the HCV-positive patients expressed NOS-2 vs 12.5% in the normal samples. p53 was not detected in either group but there was upregulation of p21 over baseline expression in a number of the HCV-positive patients. Human HCV hepatitis leads to consistent upregulation of hepatic NOS-2 message, but message is not predictably present in "normal" human liver. There is also induction of p21 in some patients with HCV hepatitis. Chronic expression of NO in HCV hepatitis may play a role in DNA mutagenesis and the development of HCC.

The rationale and ethics of medication-free research in schizophrenia

Schizophrenia research is receiving intense scrutiny from an ethical perspective. Medication-free protocols present a most vexing dilemma in that they greatly enhance the opportunity for advancing knowledge but also raise the prospect of withholding known effective treatment. In this article, we discuss the purpose of medication-free protocols in new drug development and nontreatment research. Potential benefits and risks associated with drug discontinuation are evaluated, and methods for minimizing risk and increasing benefits are proposed as guidelines for the protection of individual subjects. The complex problem of informed consent also is addressed. Medication-free research in schizophrenia is difficult, but it can be conducted relatively, safely with freely consenting, competent subjects. Assurance that studies meet this standard is required. We believe that such investigations can meet high standards of ethics and subject protection, and that a radical revision of procedures for research review and implementation is not indicated.

Is esophagectomy following upfront chemoradiotherapy safe and necessary?

OBJECTIVE

To examine the safety and necessity of esophagectomy following upfront chemoradiotherapy (CRT) in patients with potentially resectable esophageal cancer.

DESIGN

Cohort analytic study during a 4-year period.

SETTING

Tertiary referral center.

PATIENTS

Thirty-seven patients who completed CRT and underwent esophagectomy as compared with 30 patients who underwent esophagectomy alone without pretreatment during the same period.

MAIN OUTCOME MEASURES

Resection-related events, perioperative morbidity and mortality, response to CRT, site of residual disease following CRT, and survival of partial responders.

RESULTS

Patients receiving CRT followed by esophagectomy were similar to patients who underwent esophagectomy alone for operative characteristics, postoperative course, and perioperative morbidity and mortality. Of the 33 patients who achieved an objective response to CRT, 23 had residual tumor in the resection specimen. Of the 18 patients alive with no evidence of disease at a median follow-up of 30 months, 50% had residual tumor following CRT.

CONCLUSIONS

Upfront CRT did not adversely affect resection-related outcome and may facilitate resection by downstaging disease. A considerable number of patients had prolonged survival after esophageal resection despite having residual tumor present following treatment with upfront CRT. Therefore, esophagectomy following upfront CRT can improve locoregional control of disease and should remain a critical component of any multimodality regimen.

Preclinical characterization of MDL 27,192 as a potential broad spectrum anticonvulsant agent with neuroprotective properties

The compound 5-(4-chlorophenyl)-2,4-dihydro-4-ethyl-3H-1,2,4-triazol-3-one (MDL 27,192) was evaluated in a variety of rodent models to assess its anticonvulsant profile and its potential neuroprotective activity. MDL 27,192 demonstrated anticonvulsant activity in a wide range of epilepsy models that are genetically-based (audiogenic seizures in the seizure susceptible DBA/2J or Frings mouse; spike wave seizures in genetic absence epilepsy rats of Strasbourg (GAERS), electrically-based (MES seizures in mice and rats, corneally-kindled seizures in rats) and chemically-based (bicuculline, PTZ, picrotoxin, 3-mercaptopropionic acid, quinolinic acid and strychnine). When compared to valproate, orally administered MDL 27,192 was 17-48-fold more potent as an anticonvulsant and showed a safety index one to three-fold greater. Following a timed intravenous administration of PTZ to mice, MDL 27,192, but not phenytoin or carbamazepine, consistently increased the latencies to first twitch and clonus. MDL 27,192 was active in a genetic model of absence epilepsy, the GAERS rat model. These data indicate that MDL 27,192 likely exerts its anticonvulsant action by affecting seizure spread and by raising seizure threshold. MDL 27,192 did not display any signs of tolerance following subchronic (15 day) administration. In tests of neuroprotective potential, MDL 27,192 reduced infarct volume in a permanent middle cerebral artery occlusion model of focal cerebral ischemia in rats and reduced the loss of hippocampal dentate hilar neurons in an animal model of unilateral head injury. In summary, MDL 27,192 possesses a broad-spectrum anticonvulsant profile. The potential for reduced tolerance and neuroprotective activity are additional positive features of MDL 27,192's preclinical profile.

What can we achieve by implementing a compliance-improvement program?

Efforts to improve compliance and facilitate other aspects of relapse-prevention strategies can have a profound impact on the lives of millions of people around the world as well as conserving precious health-care dollars. Simultaneous efforts to educate patients and families on the nature of the disease, its course and optimum treatment, together with efforts to educate physicians and other health-care professionals on the indications, benefits and risks of long-term treatment, are critical for improving the current state of affairs. In addition, it is imperative to educate the public at large and particularly those health-care administrators and public servants who control or influence the allocation of the resources needed.

Predictive value of eosinophilia for neutropenia during clozapine treatment

BACKGROUND

Myelotoxicity continues to hinder the widespread use of clozapine in the United States. It has been theorized that eosinophilia predicts later agranulocytosis and that agranulocytosis occurs due to an immunologic mechanism. Our study compares the rates of these dyscrasias in clozapine-treated patients and a control group.

METHOD

Forty-one patients taking clozapine and 29 patients taking haloperidol were monitored for a period of 6 months. Rates of eosinophilia and neutropenia were compared between the two treatment groups.

RESULTS

Treatment-emergent eosinophilia occurred frequently in both haloperidol- and clozapine-treated patients. No significant difference was seen between groups in the incidence of eosinophilia and neutropenia.

CONCLUSION

We find no statistical difference between the rates of eosinophilia or neutropenia in haloperidol- and clozapine-treated patients. This study does not support the use of eosinophilia as a reliable predictor of neutropenia.

Serum lithium levels and psychosocial function in patients with bipolar I disorder

OBJECTIVE

This study compared the effect of two different serum lithium levels on the psychosocial functioning of patients with bipolar I disorder.

METHOD

Ninety patients with bipolar I disorder were enrolled in a prospective, double-blind, maintenance trial of lithium. The patients were randomly assigned to treatment with doses of lithium adjusted to achieve a serum lithium concentration of either 0.8 to 1.0 mmol/liter (standard) or 0.4 to 0.6 mmol/liter (low). The Longitudinal Interval Follow-Up Evaluation was used to assess psychosocial functioning in the areas of work, interpersonal relationships, and global functioning. All observed values were analyzed with a mixed-effects analysis of covariance. Independent variables included treatment group (low or standard lithium serum level), relapse status, socioeconomic status, time from random treatment assignment to assessment, termination of protocol before or after relapse, length of remission before random treatment assignment, polarity of the last mood episode before random treatment assignment, and number of mood episodes in the 3 years before random treatment assignment.

RESULTS

Relapse was associated with large negative effects on psychosocial functioning. Patients in higher socioeconomic brackets had better psychosocial functioning than did those in lower brackets. Patients receiving lithium doses that achieved standard serum levels had better psychosocial functioning than those receiving doses that achieved low serum levels; this effect was partially but not wholly mediated through relapse prevention.

CONCLUSIONS

For patients with bipolar I disorder, standard serum lithium levels may enhance psychosocial functioning, above and beyond the effects of relapse prevention.

Incidence and correlates of tardive dyskinesia in first episode of schizophrenia

BACKGROUND

There is controversy over whether tardive dyskinesia (TD) is solely a consequence of antipsychotic drug treatment or in part may reflect an intrinsic aspect of the disease process. Pathophysiologic factors could, independently or in concert with drug effects, lead to the development of dyskinetic signs.

METHODS

We studied prospectively 118 patients in their first episode of psychosis who were treatment-naive or had less than 12 weeks of antipsychotic drug exposure at study entry. Patients received standardized antipsychotic drug treatment and were evaluated for up to 8 1/2 years with regular assessments of psychopathologic signs and symptoms and side effects.

RESULTS

The cumulative incidence of presumptive TD was 6.3% after 1 year of follow-up, 11.5% after 2 years, 13.7% after 3 years, and 17.5% after 4 years. Persistent TD had a cumulative incidence of 4.8% after 1 year, 7.2% after 2 years, and 15.6% after 4 years. Taken individually, both antipsychotic drug dose, entered as a time-dependent covariate, and poor response to treatment of the first psychotic episode were significant predicters of time to TD. When antipsychotic drug dose and treatment response were examined together, treatment responders had significantly lower hazards for presumptive TD than nonresponders (hazard ratio, 0.29; 95% confidence interval, 0.09 to 0.97). Dose was a trend-level predicter, with each 100-mg chlorpromazine equivalent unit increase in dose associated with a 5% increase in the hazard of presumptive TD (hazard ratio, 1.05; 95% confidence interval, 0.99 to 1.11).

CONCLUSION

Poor response to the treatment of a first episode of psychosis and, to a lesser extent, antipsychotic drug dose are important factors in the development of TD. This suggests that there may be a disease-related vulnerability to TD manifest with antipsychotic drug exposure. Potential pathophysiologic factors might include neurodevelopmentally induced structural neuropathologic characteristics, sensitization of nigrostriatal dopamine neurons, and the induction of glutamatergically mediated neurotoxic effects.

Gender differences in neuroleptic nonresponsive clozapine-treated schizophrenics

Gender differences in neuroleptic-refractory chronic schizophrenic disorder patients were examined to determine whether a superior or equivalent antipsychotic response in women vs. men existed similar to that of the general schizophrenic population. Sixty-nine DSM-III schizophrenic patients (47 males and 22 females) were treated with clozapine using a standardized medication regime. The gender differences in these neuroleptic-nonresponsive chronic schizophrenic disorder patients differed from those previously observed in the general schizophrenic population in that an equivalent antipsychotic treatment response in females versus males was not found. These treatment-refractory women appear to be a severely ill subgroup of female schizophrenics with distinct onset of illness, course and treatment response characteristics.

Treatment-resistant schizophrenic patients

Despite the proven efficacy of antipsychotic medication in the treatment of schizophrenia, a substantial proportion of patients derive little if any benefit from traditional medications. Though alternative strategies (e.g., increasing dosage, switching antipsychotic, or adding adjunctive medication) are frequently employed, success rates are often disappointing. Clozapine has shown to be effective in some poor or partially responsive patients in three prospective, random assignment, double-blind trials. Risperidone has not yet been extensively studied in treatment-resistant patients, but may also be a useful alternative.

Medical complications of new antipsychotic drugs

Although antipsychotic drugs have a high therapeutic index (ratio of clinical benefit to adverse effects), they are associated with a range of adverse effects in most patients. The majority of these side effects are tolerable, readily managed, and not life threatening. The most troublesome side effects are neurological. Two new antipsychotics (clozapine and risperidone) have recently been introduced and are the first of a new generation of compounds that may further improve the therapeutic index of routine antipsychotic drug administration. Clozapine clearly has a reduced risk of drug-induced parkinsonism, akathisia, and tardive dyskinesia, while producing an increased risk of agranulocytosis, seizures, and weight gain. Risperidone at low doses produces relatively few parkinsonian side effects, but it can cause tardive dyskinesia (though relative risk remains to be established). Risperidone has not been associated with blood dyscrasias or increased risk of seizures, but weight gain can be a problem for some patients. Neuroleptic malignant syndrome has been reported with both drugs, but relative risk has not been established.

The enhancement of muscimol-stimulated 36C1 influx by the antispastic 5-aryl-3-(alkylsulfonyl)-4H-1,2,4-triazole (MDL 27,531) in rat brain membrane vesicles

The antispastic triazole, 4-methyl-3-methylsulphonyl-5-phenyl-4H-1,2,4-triazole (MDL 27,531) was tested in glycine- and muscimol-stimulated 36Cl- influx into brain membrane preparations. MDL 27,531 (100 nM) had no effect on glycine- (100 nM-400 microM) stimulated 36Cl- influx in brain stem tissue; on the other hand, MDL 27,531 (10 nM-10 microM) enhanced muscimol- (1 microM) stimulated 36Cl- influx in cerebellar but not cortical membranes. In the presence of the benzodiazepine (BZD) antagonist, flumazenil (10 microM), MDL 27,531 inhibited muscimol-stimulated flux. These data suggest a novel interaction of this triazole with subtypes of the gamma-aminobutyric acid (GABA)A receptor complex and the BZD receptor.

Prevalence and clinical correlates of extrapyramidal signs and spontaneous dyskinesia in never-medicated schizophrenic patients

OBJECTIVE

This study assessed the prevalence of extrapyramidal signs and spontaneous dyskinesia in neuroleptic-naive, first-episode schizophrenic patients and examined the clinical correlates.

METHOD

In a prospective study of the psychobiology of schizophrenia, the authors examined 89 neuroleptic-naive patients for the presence of extrapyramidal signs by using the Simpson-Angus Rating Scale and for dyskinesia by using the Tardive Dyskinesia Rating Scale.

RESULTS

Fifteen patients (16.9%) had extrapyramidal signs, but only one had spontaneous dyskinesia at baseline. Presence of extrapyramidal signs was correlated with more negative symptoms and poorer treatment outcome that was reflected in a longer time to and lower level of remission. There was no correlation of spontaneous extrapyramidal signs with age of patient, age at onset of psychotic symptoms, or baseline psychopathology. There was no difference between patients with and without spontaneous extrapyramidal signs in terms of the subsequent development of persistent tardive dyskinesia, but the patients with spontaneous extrapyramidal signs were more likely to develop parkinsonian side effects after 8 weeks of antipsychotic treatment.

CONCLUSIONS

Extrapyramidal signs are present in a proportion of neuroleptic-naive, first-episode schizophrenic patients, which suggests an involvement of these signs in the schizophrenic process that probably reflects basal ganglia pathology. The presence of spontaneous extrapyramidal signs seems to have prognostic significance insofar as it is linked to a poorer outcome and longer time to remission. Spontaneous dyskinesia appears to be a relatively rare finding.