Long-Term Outcome of Clozapine in Treatment-Resistant Schizophrenia

PURPOSE/BACKGROUND

The favorable effect of clozapine on psychotic symptoms in patients with treatment-resistant (TR) schizophrenia (SCZ) in short-term studies is well established. However, prospective studies of the long-term outcome of clozapine treatment on psychopathology, cognition, quality of life, and functional outcome in TR-SCZ are limited.

METHODS/PROCEDURES

Here, we have examined the long-term (mean duration of follow-up 14 years) effects of clozapine on those outcomes in a prospective, open label study in 54 TR-SCZ patients. Assessments were performed at baseline, 6 weeks, 6 months, and at the last follow-up.

FINDINGS/RESULTS

Brief Psychiatric Rating Scale (BPRS) total, positive symptoms, and anxiety/depression at the last follow-up improved significantly from baseline, as well as from the 6-month evaluation ( P < 0.0001), with a 70.5% responder rate (≥20% improvement at the last follow-up from baseline). Quality of Life Scale (QLS) total improved by 72% at the last follow-up, with 24% of patients rated as having "good" functioning compared with 0% at baseline. Suicidal thoughts/behavior was significantly reduced at the last follow-up from the baseline. No significant change in negative symptoms was found at the last follow-up in the total sample. Short-term memory function declined at the last follow-up from baseline, but there was no significant change in processing speed. The QLS total showed a significant negative correlation with BPRS positive symptoms but not with cognitive measures, or negative symptoms, at the last follow-up.

IMPLICATIONS/CONCLUSIONS

For patients with TR-SCZ, improving psychotic symptoms with clozapine seems to have a more significant impact than negative symptoms or cognition on improving psychosocial function.

Site-Level Comprehensiveness of Care Is Associated with Individual Clinical Retention Among Adults Living with HIV in International Epidemiology Databases to Evaluate AIDS, a Global HIV Cohort Collaboration, 2000-2016

Retention in care (RIC) reduces HIV transmission and associated morbidity and mortality. We examined whether delivery of comprehensive services influenced individual RIC within the International epidemiology Databases to Evaluate AIDS (IeDEA) network. We collected site data through IeDEA assessments 1.0 (2000-2009) and 2.0 (2010-2016). Each site received a comprehensiveness score for service availability (1 = present, 0 = absent), with tallies ranging from 0 to 7. We obtained individual-level cohort data for adults with at least one visit from 2000 to 2016 at sites responding to either assessment. Person-time was recorded annually, with RIC defined as completing two visits at least 90 days apart in each calendar year. Multivariable modified Poisson regression clustered by site yielded risk ratios and predicted probabilities for individual RIC by comprehensiveness. Among 347,060 individuals in care at 122 sites with 1,619,558 person-years of follow-up, 69.8% of person-time was retained in care, varying by region from 53.8% (Asia-Pacific) to 82.7% (East Africa); RIC improved by about 2% per year from 2000 to 2016 (p = 0.012). Every site provided CD4+ count testing, and >90% of individuals received care at sites that provided combination antiretroviral therapy adherence measures, prevention of mother-to-child transmission, tuberculosis screening, HIV-related prevention, and community tracing services. In adjusted models, individuals at sites with more comprehensive services had higher probabilities of RIC (0.71, 0.74, and 0.83 for scores 5, 6, and 7, respectively; p = 0.019). Within IeDEA, greater site-level comprehensiveness of services was associated with improved individual RIC. Much work remains in exploring this relationship, which may inform HIV clinical practice and health systems planning.

The IeDEA harmonist data toolkit: A data quality and data sharing solution for a global HIV research consortium

We describe the design, implementation, and impact of a data harmonization, data quality checking, and dynamic report generation application in an international observational HIV research network. The IeDEA Harmonist Data Toolkit is a web-based application written in the open source programming language R, employs the R/Shiny and RMarkdown packages, and leverages the REDCap data collection platform for data model definition and user authentication. The Toolkit performs data quality checks on uploaded datasets, checks for conformance with the network's common data model, displays the results both interactively and in downloadable reports, and stores approved datasets in secure cloud storage for retrieval by the requesting investigator. Including stakeholders and users in the design process was key to the successful adoption of the application. A survey of regional data managers as well as initial usage metrics indicate that the Toolkit saves time and results in improved data quality, with a 61% mean reduction in the number of error records in a dataset. The generalized application design allows the Toolkit to be easily adapted to other research networks.

Tuberculosis treatment intermittency in the continuation phase and mortality in HIV-positive persons receiving antiretroviral therapy

BACKGROUND

Some tuberculosis (TB) treatment guidelines recommend daily TB treatment in both the intensive and continuation phases of treatment in HIV-positive persons to decrease the risk of relapse and acquired drug resistance. However, guidelines vary across countries, and treatment is given 7, 5, 3, or 2 days/week. The effect of TB treatment intermittency in the continuation phase on mortality in HIV-positive persons on antiretroviral therapy (ART), is not well-described.

METHODS

We conducted an observational cohort study among HIV-positive adults treated for TB between 2000 and 2018 and after enrollment into the Caribbean, Central, and South America network for HIV epidemiology (CCASAnet; Brazil, Chile, Haiti, Honduras, Mexico and Peru). All received standard TB therapy (2-month initiation phase of daily isoniazid, rifampin or rifabutin, pyrazinamide ± ethambutol) and continuation phase of isoniazid and rifampin or rifabutin, administered concomitantly with ART. Known timing of ART and TB treatment were also inclusion criteria. Kaplan-Meier and Cox proportional hazards methods compared time to death between groups. Missing model covariates were imputed via multiple imputation.

RESULTS

2303 patients met inclusion criteria: 2003(87%) received TB treatment 5-7 days/week and 300(13%) 2-3 days/week in the continuation phase. Intermittency varied by site: 100% of patients from Brazil and Haiti received continuation phase treatment 5-7 days/week, followed by Honduras (91%), Peru (42%), Mexico (7%), and Chile (0%). The crude risk of death was lower among those receiving treatment 5-7 vs. 2-3 days/week (HR = 0.68; 95% CI = 0.51-0.91; P = 0.008). After adjusting for age, sex, CD4, ART use at TB diagnosis, site of TB disease (pulmonary vs. extrapulmonary), and year of TB diagnosis, mortality risk was lower, but not significantly, among those treated 5-7 days/week vs. 2-3 days/week (HR 0.75, 95%CI 0.55-1.01; P = 0.06). After also stratifying by study site, there was no longer a protective effect (HR 1.42, 95%CI 0.83-2.45; P = 0.20).

CONCLUSIONS

TB treatment 5-7 days/week was associated with a marginally decreased risk of death compared to TB treatment 2-3 days/week in the continuation phase in multivariable, unstratified analyses. However, little variation in TB treatment intermittency within country meant the results could have been driven by other differences between study sites. Therefore, randomized trials are needed, especially in heterogenous regions such as Latin America.

Cardiovascular disease among people living with HIV in Brazil

OBJECTIVES

There is a paucity of data on cardiovascular disease (CVD) among people living with HIV (PLHIV) in resource-limited countries. We assessed factors associated with CVD and the impact of prevalent CVD on all-cause mortality in PLHIV on antiretroviral therapy in Brazil.

METHODS

Competing risk regression to assess factors associated with CVD and all-cause mortality in the HIV-Brazil Cohort Study between 2003 and 2014.

RESULTS

Among 5614 patients, the rate of CVD was 3.5 (95% confidence interval [95% CI] 2.9-4.3) per 1000 person-years. CVD was associated with older age (adjusted hazard ratio [aHR] 6.4 for ≥55 years vs. <35 years, 95% CI: 2.5-16.3, P < 0.01), black race (aHR 1.8 vs. white race, 95% CI: 1.0-3.1, P = 0.04), past CVD (aHR 3.0 vs. no past CVD, 95% CI: 1.4-6.2, P < 0.01), hypertension (aHR 1.8 vs. no hypertension, 95% CI: 1.0-3.1, P = 0.04), high-grade dyslipidemia (aHR 9.3 vs. no high-grade dyslipidemia, 95% CI: 6.0-14.6, P < 0.01), ever smoking (aHR 2.4 vs. never, 95% CI: 1.2-5.0, P = 0.02) and low nadir CD4 cell count (aHR 1.8 for 100-250 cells/mm3 vs. >250 cells/mm3 , 95% CI: 1.0-3.2, P = 0.05). The rate of death was 16.6 (95% CI: 15.1-18.3) per 1000 person-years. Death was strongly associated with having had a past CVD event (aHR 1.7 vs. no past CVD event, 95% CI: 1.1-2.7, P = 0.01).

CONCLUSIONS

Traditional and HIV-specific factors associated with CVD among PLHIV in Brazil are similar to those identified among PLHIV in high-income countries. PLHIV in Brazil with a history of CVD have a high risk of death. CVD care and treatment remain priorities for PLHIV in Brazil as this population ages and antiretroviral therapy use expands.

HIV-related tuberculosis: mortality risk in persons without vs. with culture-confirmed disease

BACKGROUND

Tuberculosis (TB) diagnosis in human immunodeficiency virus (HIV) positive persons is difficult, particularly in resource-limited settings. The relationship between TB culture status and mortality in HIV-positive persons treated for TB is unclear.

METHODS

We evaluated HIV-positive adults treated for TB at or after their first HIV clinic visit in Argentina, Brazil, Chile, Honduras, Mexico or Peru from 2000 to 2015. Anti-tuberculosis treatment included 2 months of isoniazid, rifampicin (RMP)/rifabutin (RBT), pyrazinamide ± ethambutol, followed by continuation phase treatment with isoniazid + RMP/RBT.

RESULTS

Of 759 TB-HIV patients, 238 (31%) were culture-negative, 228 (30%) had unknown culture status or did not undergo culture and 293 (39%) were culture-positive. The median CD4 at TB diagnosis was 96 (interquartile range 40-228); 636 (84%) received concurrent antiretroviral therapy (ART) and anti-tuberculosis treatment. There were 123 (16%) deaths: 90/466 (19%) with TB culture-negative, unknown or not performed vs. 33/293 (11%) who were TB culture-positive (P = 0.005). In Kaplan-Meier analysis, mortality in TB patients without culture-confirmed disease was higher (P = 0.002). In a Cox model adjusted for age, sex, CD4, ART timing, disease site and stratified by study site, mortality in persons without culture-confirmed TB was not significantly increased compared to those with culture-positive TB (hazard ratio 1.39, 95%CI 0.89-2.16, P = 0.15).

CONCLUSION

Most HIV-positive patients treated for TB did not have culture-confirmed TB, and mortality tended to be higher in patients without culture-confirmed disease, although the association was not statistically different after adjusting for other variables. Accurate TB diagnosis in HIV-positive persons is crucial.

Trends and predictors of non-communicable disease multimorbidity among adults living with HIV and receiving antiretroviral therapy in Brazil

INTRODUCTION

People living with HIV (PLHIV) on antiretroviral therapy (ART) experience high rates of non-communicable diseases (NCDs). These co-morbidities often accumulate and older adults may suffer from multimorbidity. Multimorbidity has been associated with loss of quality of life, polypharmacy, and increased risk of frailty and mortality. Little is known of the trends or predictors NCD multimorbidity in PLHIV in low- and middle-income countries.

METHODS

We examined NCD multimorbidity in adult PLHIV initiating ART between 2003 and 2014 using a multi-site, observational cohort in Brazil. NCDs included cardiovascular artery disease, hyperlipidemia (HLD), diabetes, chronic kidney disease, cirrhosis, osteoporosis, osteonecrosis, venous thromboembolism and non-AIDS-defining cancers. Multimorbidity was defined as the incident accumulation of two or more unique NCDs. We used Poisson regression to examine trends and Cox proportional hazard models to examine predictors of multimorbidity.

RESULTS

Of the 6206 adults, 332 (5%) developed multimorbidity during the study period. Parallel to the ageing of the cohort, the prevalence of multimorbidity rose from 3% to 11% during the study period. Older age, female sex (adjusted hazard ratio (aHR) = 1.30 (95% confidence interval (CI) 1.03 to 1.65)) and low CD4 nadir (<100 vs. ≥200 cells/mm3 aHR = 1.52 (95% CI: 1.15 to 2.01)) at cohort entry were significantly associated with increased risk of multimorbidity. Among patients with incident multimorbidity, the most common NCDs were HLD and diabetes; however, osteoporosis was also frequent in women (16 vs. 35% of men and women with multimorbidity respectively).

CONCLUSIONS

Among adult PLHIV in Brazil, NCD multimorbidity increased from 2003 to 2014. Females and adults with low CD4 nadir were at increased risk in adjusted analyses. Further studies examining prevention, screening and management of NCDs in PLHIV in low- and middle-income countries are needed.

A within-subject consideration of the psychotic spectrum disorder concept in a patient in remission associated with cortical gray matter recovery

INTRODUCTION

Psychotic spectrum disorder (PSD) links the syndromes of bipolar disorder, psychotic depression, and schizophrenia, often viewed as unique disorders.

AIMS

Application of the PSD concept to a single patient rather than across groups of patients and demonstration of a remarkable remission of schizophrenia phenotype with recovery of gray matter in specific brain regions.

RESULTS

We report a woman who experienced discrete, nonoverlapping periods of each of the above syndromes, in the order noted, over a 30-year period, followed by abrupt ending of psychosis and full remission lasting at least 7 years. This patient had 2 episodes of Bipolar 1 mania, followed by a 20-year period of psychotic depression. From ages 35-48, she manifested severe, paranoid schizophrenia with marked functional decline. She became refractory to antipsychotic drugs, including oral risperidone and clozapine. At age 48, while participating in a double-blind, 6-month clinical trial of long-acting injectable risperidone (Consta®, 100 mg IM biweekly) for treatment-resistant schizophrenia, at week 23, upon awakening, complete disappearance of psychosis and marked improvement in function was noted, which persisted until the present (approximately 7 years). Remarkably, cognitive test performance in most domains improved beginning at 6 weeks and reached normal levels in executive function, despite minimal improvement in psychosis until week 23. MRI studies before and after remission revealed unique and substantial increases in gray matter of the cingulate and parietal cortex, and subthalamic nucleus, not seen in other patients in this study.

CONCLUSIONS

The 3 discrete periods of psychopathology support the diagnosis of PSD. The unusual course and outcome, including remarkable improvement, in executive function and enhanced cortical gray matter in selective brain regions may have been the result of unique endogenous genetic and epigenetic factors and effect of medication.

Survival after cancer diagnosis in a cohort of HIV-positive individuals in Latin America

BACKGROUND

This study aimed to evaluate trends and predictors of survival after cancer diagnosis in persons living with HIV in the Caribbean, Central, and South America network for HIV epidemiology cohort.

METHODS

Demographic, cancer, and HIV-related data from HIV-positive adults diagnosed with cancer ≤ 1 year before or any time after HIV diagnosis from January 1, 2000-June 30, 2015 were retrospectively collected. Cancer cases were classified as AIDS-defining cancers (ADC) and non-AIDS-defining cancers (NADC). The association of mortality with cancer- and HIV-related factors was assessed using Kaplan-Meier curves and Cox proportional hazards models stratified by clinic site and cancer type.

RESULTS

Among 15,869 patients, 783 had an eligible cancer diagnosis; 82% were male and median age at cancer diagnosis was 39 years (interquartile range [IQR]: 32-47). Patients were from Brazil (36.5%), Argentina (19.9%), Chile (19.7%), Mexico (19.3%), and Honduras (4.6%). A total of 564 ADC and 219 NADC were diagnosed. Patients with NADC had similar survival probabilities as those with ADC at one year (81% vs. 79%) but lower survival at five years (60% vs. 69%). In the adjusted analysis, risk of mortality increased with detectable viral load (adjusted hazard ratio [aHR] = 1.63, p = 0.02), age (aHR = 1.02 per year, p = 0.002) and time between HIV and cancer diagnoses (aHR = 1.03 per year, p = 0.01).

CONCLUSION

ADC remain the most frequent cancers in the region. Overall mortality was related to detectable viral load and age. Longer-term survival was lower after diagnosis of NADC than for ADC, which may be due to factors unrelated to HIV.

Virologic failure and mortality in older ART initiators in a multisite Latin American and Caribbean Cohort

INTRODUCTION

The "greying" of the HIV epidemic necessitates a better understanding of the healthcare needs of older HIV-positive adults. As these individuals age, it is unclear whether comorbidities and their associated therapies or the ageing process itself alter the response to antiretroviral therapy (ART). In this study, HIV treatment outcomes and corresponding risk factors were compared between older ART initiators and those who were younger using data from the Caribbean, Central and South America Network for HIV Epidemiology (CCASAnet).

METHODS

HIV-positive adults (≥18 years) initiating ART at nine sites in Argentina, Brazil, Chile, Haiti, Honduras, Mexico and Peru were included. Patients were classified as older (≥50 years) or younger (<50 years) based on age at ART initiation. ART effectiveness was measured using three outcomes: death, virologic failure and ART treatment modification. Cox regression models for each outcome compared risk between older and younger patients, adjusting for other covariates.

RESULTS

Among 26,311 patients initiating ART between 1996 and 2016, 3389 (13%) were ≥50 years. The majority of patients in both ≥50 and <50 age groups received a non-nucleoside reverse transcriptase inhibitor-based regimen (89% vs. 87%), did not have AIDS at baseline (63% vs. 62%), and were male (59% vs. 58%). Older patients had a higher risk of death (adjusted hazard ratio (aHR) 1.64; 95% confidence intervals (CI): 1.48 to 1.83) and a lower risk of virologic failure (aHR: 0.73; 95% CI: 0.63 to 0.84). There was no difference in risk of ART modification (aHR: 1.00; 95% CI: 0.94 to 1.06). Risk factors for death, virologic failure and treatment modification were similar for each group.

CONCLUSIONS

Older age at ART initiation was associated with increased mortality and decreased risk of virologic failure in our cohort of more than 26,000 ART initiators in Latin America and the Caribbean. To the best of our knowledge this is the first study from the region to evaluate ART outcomes in this growing and important population. Given the complexity of issues related to ageing with HIV, a greater understanding is needed in order to properly respond to this shifting epidemic.

Comparison of Kaposi Sarcoma Risk in Human Immunodeficiency Virus-Positive Adults Across 5 Continents: A Multiregional Multicohort Study

BACKGROUND

We compared Kaposi sarcoma (KS) risk in adults who started antiretroviral therapy (ART) across the Asia-Pacific, South Africa, Europe, Latin, and North America.

METHODS

We included cohort data of human immunodeficiency virus (HIV)-positive adults who started ART after 1995 within the framework of 2 large collaborations of observational HIV cohorts. We present incidence rates and adjusted hazard ratios (aHRs).

RESULTS

We included 208140 patients from 57 countries. Over a period of 1066572 person-years, 2046 KS cases were diagnosed. KS incidence rates per 100000 person-years were 52 in the Asia-Pacific and ranged between 180 and 280 in the other regions. KS risk was 5 times higher in South African women (aHR, 4.56; 95% confidence intervals [CI], 2.73-7.62) than in their European counterparts, and 2 times higher in South African men (2.21; 1.34-3.63). In Europe, Latin, and North America KS risk was 6 times higher in men who have sex with men (aHR, 5.95; 95% CI, 5.09-6.96) than in women. Comparing patients with current CD4 cell counts ≥700 cells/µL with those whose counts were <50 cells/µL, the KS risk was halved in South Africa (aHR, 0.53; 95% CI, .17-1.63) but reduced by ≥95% in other regions.

CONCLUSIONS

Despite important ART-related declines in KS incidence, men and women in South Africa and men who have sex with men remain at increased KS risk, likely due to high human herpesvirus 8 coinfection rates. Early ART initiation and maintenance of high CD4 cell counts are essential to further reducing KS incidence worldwide, but additional measures might be needed, especially in Southern Africa.

Time to HAART Initiation after Diagnosis and Treatment of Opportunistic Infections in Patients with AIDS in Latin America

Background

Since 2009, earlier initiation of highly active antiretroviral therapy (HAART) after an opportunistic infection (OI) has been recommended based on lower risks of death and AIDS-related progression found in clinical trials. Delay in HAART initiation after OIs may be an important barrier for successful outcomes in patients with advanced disease. Timing of HAART initiation after an OI in “real life” settings in Latin America has not been evaluated.

Methods

Patients in the Caribbean, Central and South America network for HIV Epidemiology (CCASAnet) ≥18 years of age at enrolment, from 2001–2012 who had an OI before HAART initiation were included. Patients were divided in an early HAART (EH) group (those initiating within 4 weeks of an OI) and a delayed HAART (DH) group (those initiating more than 4 weeks after an OI). All patients with an AIDS-defining OI were included. In patients with more than one OI the first event reported was considered. Calendar trends in the proportion of patients in the EH group (before and after 2009) were estimated by site and for the whole cohort. Factors associated with EH were estimated using multivariable logistic regression models.

Results

A total of 1457 patients had an OI before HAART initiation and were included in the analysis: 213 from Argentina, 686 from Brazil, 283 from Chile, 119 from Honduras and 156 from Mexico. Most prevalent OI were Tuberculosis (31%), followed by Pneumocystis pneumonia (24%), Invasive Candidiasis (16%) and Toxoplasmosis (9%). Median time from OI to HAART initiation decreased significantly from 5.7 (interquartile range [IQR] 2.8–12.1) weeks before 2009 to 4.3 (IQR 2.0–7.1) after 2009 (p<0.01). Factors associated with starting HAART within 4 weeks of OI diagnosis were lower CD4 count at enrolment (p-<0.001), having a non-tuberculosis OI (p<0.001), study site (p<0.001), and more recent years of OI diagnosis (p<0.001).

Discussion

The time from diagnosis of an OI to HAART initiation has decreased in Latin America coinciding with the publication of evidence of its benefit. We found important heterogeneity between sites which may reflect differences in clinical practices, local guidelines, and access to HAART. The impact of the timing of HAART initiation after OI on patient survival in this “real life” context needs further evaluation.

Temporal Trends in Age at HIV Diagnosis in Cohorts in the United States, the Caribbean, and Central and South America

In the United States (USA), the age of those newly diagnosed with HIV is changing, particularly among men who have sex with men (MSM). A retrospective analysis included HIV-infected adults from seven sites in the Caribbean, Central and South America network (CCASAnet) and the Vanderbilt Comprehensive Care Clinic (VCCC-Nashville, Tennessee, USA). We estimated the proportion of patients <25 years at HIV diagnosis by calendar year among the general population and MSM. 19,466 (CCASAnet) and 3,746 (VCCC) patients were included. The proportion <25 years at diagnosis in VCCC increased over time for both the general population and MSM (p < 0.001). Only in the Chilean site for the general population and the Brazilian site for MSM were similar trends seen. Subjects <25 years of age at diagnosis were less likely to be immunocompromised at enrollment at both the VCCC and CCASAnet. Recent trends in the USA of greater numbers of newly diagnosed young patients were not consistently observed in Latin America and the Caribbean. Prevention efforts tailored to young adults should be increased.

A six month randomized controlled trial of long acting injectable risperidone 50 and 100mg in treatment resistant schizophrenia

It has been suggested that atypical antipsychotic drugs (A-APDs) other than clozapine may be effective to improve positive symptoms in some patients with treatment resistant schizophrenia (TRS), if both the dose is higher, and the duration of the trial longer, than those which have been ineffective in non-TRS (NTRS) patients. This hypothesis was tested with long acting injectable risperidone (Risperdal Consta®, RLAI). One hundred sixty TRS patients selected for persistent moderate-severe delusions or hallucinations, or both, were randomized to RLAI, 50 or 100mg biweekly, in a six month, outpatient, double-blind, multicenter trial. We hypothesized that RLAI, 100mg, would be more effective than RLAI, 50mg. However, both doses produced clinically significant and equivalent improvement in PANSS Total, Positive, and Negative subscale scores, as well as key cognitive, global and functional measures, with increasing response during the course of the study, confirming the value of longer clinical trial duration for patients with TRS, but not superiority of the higher dose. The overall response rate was comparable to that previously reported for clozapine and high dose olanzapine, another A-APD, in TRS. Both doses of RLAI were equally well tolerated, producing minimal extrapyramidal side effects and few drop outs. Plasma levels of the active moiety, risperidone+9-hydroxyrisperidone, during treatment with RLAI 100mg, were comparable to those for 6-8 mg/day oral risperidone, which have not been effective in TRS. Further study of RLAI, ≥ 50-100mg biweekly, should compare it with clozapine and oral risperidone in TRS, with duration of treatment ≥ six months.

D(1) receptor agonists reverse the subchronic phencyclidine (PCP)-induced novel object recognition (NOR) deficit in female rats

Development of dopamine (DA) D(1) receptor agonists is a priority to improve cognitive impairment in schizophrenia (CIS). This study examined the dose-response relationship of the selective D(1) agonist, SKF38393 (0.5-40 mg/kg), to reverse the deficit in novel object recognition (NOR), an analog of declarative memory in man, produced by subchronic phencyclidine (PCP), an N-methyl-D-aspartate (NMDA) receptor non-competitive antagonist, and the ability of the D(1) antagonists, SCH23390 (0.05 mg/kg) and SKF83566 (0.15 mg/kg), to impair NOR in normal Long-Evans female rats. We also examined the ability of tandospirone, a serotonin (5-HT)(1A) receptor partial agonist, and LY341495, a mGluR2/3 receptor antagonist, to potentiate or block the effects of SKF38393 on NOR, respectively. SKF38393 reversed the persistent NOR deficit produced by subchronic PCP; the dose-response curve for SKF38393 was an inverted U-shape, with the peak effect at 6 mg/kg. SKF83566 and SCH23390 impaired NOR in normal rats. Co-administration of sub-effective doses of SKF38393 (0.25 mg/kg) and tandospirone (0.2 mg/kg) improved the PCP-induced NOR deficit, while LY341495 (1 mg/kg) blocked the ameliorating effect of SKF38393 (6 mg/kg), respectively. These data provide the first evidence that the reversal of the PCP-induced NOR deficit by D(1) agonism has an inverted U-shaped dose-response curve and that 5-HT(1A) and mGluR2/3 receptor signalling facilitates the efficacy of D(1) agonism to improve these deficits. These data suggest that although D(1) agonists may be useful to improve CIS, these agents, particularly higher doses, may also worsen cognitive function in some patients, because of an inverted U-shaped dose response curve.

Investigating association of four gene regions (GABRB3, MAOB, PAH, and SLC6A4) with five symptoms in schizophrenia

Recently, microsatellite polymorphisms have been reported to be associated with four genes, GABRB3, MAOB, PAH, and SLC6A4, and their relationships have been tested to five symptom factors: hallucinations, delusions, negative symptoms, mania, and depression. These factors were frequently present in schizophrenia spectrum disorders in the Irish Study of High Density Schizophrenia Families (ISHDSF) with a proband with the diagnosis of schizophrenia (Bergen et al., 2009). Of these, GABRB3 and PAH were reported to be significantly associated with hallucinations and delusions in a 90-family subset of the ISHDSF, respectively. In this study, we tested the association of genetic markers from these four gene regions with the approximate five clinical symptoms, based upon 256 schizophrenia patients, with genotypic data obtained by higher resolution single nucleotide polymorphism (SNP) genotyping. We found one GABRB3 SNP (rs1426891, 70.8kb downstream of this gene) and haplotype constructed by three SNPs (rs1426891, rs2912602, and rs2912600) were significantly associated with hallucinations in Caucasians after Bonferroni correction for multiple testing (Bonferroni corrected P: 0.032 and 0.016, respectively). Additionally, we found one haplotype constructed by two SNPs, rs5905587-rs37615860, in MAOB/NDP gene region was significantly associated with delusions in all samples tested (Bonferroni corrected P: 0.048). These results provide additional evidence that GABRB3 and MAOB/NDP gene regions might constitute risk factors for hallucinations and delusions in schizophrenia.

Evidence for a SULT4A1 haplotype correlating with baseline psychopathology and atypical antipsychotic response

AIM

This study evaluated the impact of SULT4A1 gene variation on psychopathology and antipsychotic drug response in Caucasian subjects from the Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study and a replication sample.

PATIENTS & METHODS

SULT4A1 haplotypes were determined using SNP data. The relationship to baseline psychopathology was evaluated using linear regression of Positive and Negative Syndrome Scale (PANSS) total score. Drug response was evaluated using Mixed Model Repeat Measures (MMRM) for change in PANSS.

RESULTS

For the CATIE sample, patients carrying a haplotype designated SULT4A1-1(+) displayed higher baseline PANSS (p = 0.03) and, when treated with olanzapine, demonstrated a significant interaction with time (p = 0.009) in the MMRM. SULT4A1-1(+) patients treated with olanzapine displayed improved response compared with SULT4A1-1(-) patients treated with olanzapine (p = 0.008) or to SULT4A1-1(+) patients treated with risperidone (p = 0.006). In the replication sample, SULT4A1-1(+) patients treated with olanzapine demonstrated greater improvement than SULT4A1-1(-) patients treated with olanzapine (p = 0.05) or than SULT4A1-1(+) patients treated with risperidone (p = 0.05).

CONCLUSION

If validated, determination of SULT4A1-1 haplotype status might be useful for identifying patients who show an enhanced response to long-term olanzapine treatment. Original submitted 6 October 2010; Revision submitted 9 December 2010.

Decreased plasma tryptophan and tryptophan/large neutral amino acid ratio in patients with neuroleptic-resistant schizophrenia: relationship to plasma cortisol concentration

Tryptophan is the precursor of kynurenine and kynurenic acid, an α-7 nicotinic acetylcholine receptor antagonist and a N-methyl-D-aspartate (NMDA) receptor antagonist, both of which have been implicated in schizophrenia (SCH), as well as of serotonin. Glucocorticoids can activate the tryptophan-kynurenine pathway and lower plasma tryptophan concentrations. Some previous studies have reported decreases in the plasma tryptophan concentration and the tryptophan/large neutral amino acid (LNAA) ratio, a measure reflecting the brain tryptophan concentration, in patients with SCH. However, the influence of plasma cortisol, which has been reported to be increased in patients with SCH, on plasma tryptophan levels has not been examined in prior studies. Thus, we examined plasma tryptophan concentrations, tryptophan/LNAA ratios, and their relationships with plasma cortisol concentrations in treatment-resistant SCH (TR-SCH) patients, in non-treatment-resistant SCH (NTR-SCH) patients, and in normal controls (NC). Plasma tryptophan concentrations were significantly lower in TR-SCH patients (n=74) than in NTR-SCH patients (n=85) and NC subjects (n=55). In addition, tryptophan/LNAA ratios were significantly lower in TR-SCH patients than in NC subjects. No difference was observed in either measure between NTR-SCH patients and NC subjects. Tryptophan/LNAA ratios and plasma tryptophan concentrations showed a significant negative correlation and a trend-level correlation, respectively, with plasma cortisol concentrations in TR-SCH patients, but not in NTR-SCH patients or in NC subjects. These results suggest the tryptophan-kynurenine pathway may be particularly relevant to TR-SCH and that this may be influenced by the activity of the hypothalamic-pituitary-adrenal axis.

A genome-wide investigation of SNPs and CNVs in schizophrenia

We report a genome-wide assessment of single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) in schizophrenia. We investigated SNPs using 871 patients and 863 controls, following up the top hits in four independent cohorts comprising 1,460 patients and 12,995 controls, all of European origin. We found no genome-wide significant associations, nor could we provide support for any previously reported candidate gene or genome-wide associations. We went on to examine CNVs using a subset of 1,013 cases and 1,084 controls of European ancestry, and a further set of 60 cases and 64 controls of African ancestry. We found that eight cases and zero controls carried deletions greater than 2 Mb, of which two, at 8p22 and 16p13.11-p12.4, are newly reported here. A further evaluation of 1,378 controls identified no deletions greater than 2 Mb, suggesting a high prior probability of disease involvement when such deletions are observed in cases. We also provide further evidence for some smaller, previously reported, schizophrenia-associated CNVs, such as those in NRXN1 and APBA2. We could not provide strong support for the hypothesis that schizophrenia patients have a significantly greater "load" of large (>100 kb), rare CNVs, nor could we find common CNVs that associate with schizophrenia. Finally, we did not provide support for the suggestion that schizophrenia-associated CNVs may preferentially disrupt genes in neurodevelopmental pathways. Collectively, these analyses provide the first integrated study of SNPs and CNVs in schizophrenia and support the emerging view that rare deleterious variants may be more important in schizophrenia predisposition than common polymorphisms. While our analyses do not suggest that implicated CNVs impinge on particular key pathways, we do support the contribution of specific genomic regions in schizophrenia, presumably due to recurrent mutation. On balance, these data suggest that very few schizophrenia patients share identical genomic causation, potentially complicating efforts to personalize treatment regimens.

Association of Sult4A1 SNPs with psychopathology and cognition in patients with schizophrenia or schizoaffective disorder

A number of genes located on chromosome 22q11-13, including catechol-O-methyltransferase (COMT), are potential schizophrenia susceptibility genes. Recently, the sulfotransferase-4A1 (Sult4A1) locus within chromosome 22q13 was reported to be linked to schizophrenia in a family TDT study. Sult4A1 is related to metabolism of monoamines, particularly dopamine and norepinephrine, both of which have been implicated in the pathophysiology of the psychopathology and cognitive dysfunction components of schizophrenia. An available, prospectively collected data base was interrogated to determine how three Sult4A1 SNPs: rs138060, rs138097, and rs138110, previously shown to be associated with schizophrenia might be associated with psychopathology, cognition, and quality of life in a sample of 86 Caucasian patients with schizophrenia or schizoaffective disorder. The majority of patients met criteria for treatment resistant schizophrenia and had been drug-free for one week or longer at the time of evaluation. The major findings were: 1) patients heterozygous (T/G) for rs138060 had significantly worse Brief Psychiatric Rating Scale (BPRS) Total and anxiety/depression sub-scale scores, and higher Scale for the Assessment of Positive Symptoms (SAPS) Total scores than G/G homozygous patients; and 2) patients heterozygous (A/G) for rs138097 demonstrated significantly worse performance on neuropsychological testing, specifically on tests of executive function and working memory, compared to patients homozygous for the G and A alleles. RS138110 was unrelated to psychopathology and cognition. These results provide the first evidence of how genetic variation in Sult4A1 may be related to clinical symptoms and cognitive function in schizophrenia, and permit future studies to attempt to replicate these potentially important findings.

The InterSePT suicide scale for prediction of imminent suicidal behaviors

The present study examined the ability of the International Suicide Prevention Trial (InterSePT) Scale for Suicidal Thinking (ISST) and the Calgary Depression Scale (CDS) to predict suicide attempts or hospitalizations to prevent attempts (referred to as Type 1 events) during the InterSePT trial [Meltzer, H.Y., Alphs, L., Green, A.I., Altamura, A.C., Anand, R., Bertoldi, A., Bourgeois, M., Chouinard, G., Islam, M.Z., Kane, J., Krishman, R., Lindenmayer, J.P., Potkin, S., 2003. Clozapine treatment for suicidality in schizophrenia. Archive of General Psychiatry 60, 82-91]. The primary goal of this analysis was to determine if the ISST and CDS ratings indicated that the raters, an unblinded (UP) and a blinded psychiatrist (BP) using the ISST, and a blinded rater using the CDS, were able to identify those patients who had a Type 1 event. The ratings of patients adjudged to have experienced a Type 1 event (Group 1) were compared with patients who did not (Group 2). The ISST and the CDS ratings obtained 2-8 weeks prior to a Type 1 event (Pre-1) and Pre-2, the rating immediately prior to Pre-1, obtained 2-12 weeks before Pre-1, were analyzed to test the hypothesis that the difference between Pre-2 and Pre-1 ratings for the Group 1 patients was significantly greater than the difference in the comparable ratings for Group 2 patients. The prediction that patients with Type 1 events would show greater worsening in ISST and CDS ratings between Pre-2 and Pre-1 than the Group 2 patients was confirmed. However, the sensitivity and specificity of a worsening in ratings was not sufficient to provide definitive warning of an impending Type 1 event. Other characteristics of the patients with Type 1 events provide additional warning: e.g. overall higher ratings on these scales, slower improvement in suicidality during treatment, and previous number of suicide attempts. These results indicate that the ISST and CDS may provide some additional information that can assist clinical decision making regarding suicidal risk in patients with schizophrenia or schizoaffective disorder.

A randomized, double-blind comparison of clozapine and high-dose olanzapine in treatment-resistant patients with schizophrenia

BACKGROUND

Clozapine, despite its side-effect burden, has been considered to be the drug of choice for patients with schizophrenia whose psychotic symptoms fail to respond adequately to other anti-psychotic drugs. There are conflicting data concerning the potential utility of olanzapine in treatment-resistant schizophrenia at doses beyond the 10- to 20-mg/day range that has proven to be effective for most nonrefractory patients with schizophrenia.

OBJECTIVE

The main objective of this study was to compare the efficacy and tolerability of high-dose olanzapine (target dose, 25-45 mg/day) and clozapine (300-900 mg/day) in patients with schizophrenia or schizoaffective disorder who had failed to respond adequately to prior treatment with other antipsychotic drugs.

STUDY DESIGN/METHOD

This 6-month, randomized, double-blind, parallel-group study compared the efficacy and tolerability of olanzapine (mean dose, 34 mg/day; N = 19) or clozapine (mean dose, 564 mg/day; N = 21) in patients with treatment-resistant schizophrenia or schizoaffective disorder, diagnosed according to DSM-IV criteria. Outcome measures included psychopathology, cognitive performance (as assessed with a comprehensive neuropsychological test battery), and tolerability. The study was conducted between May 2000 and December 2003.

RESULTS

Robust and significant (mostly p < .001) improvement in multiple measures of psychopathology, mainly between 6 weeks and 6 months of treatment, was found in both treatment groups, with no significant difference between the 2 treatments except for the Global Assessment of Functioning score, which favored clozapine (p = .01). Improvement in some domains of cognition was significant-and equivalent for both drugs, as well. Nonsignificantly different improvement in Verbal List Learning-Immediate Recall (p < .05), Controlled Word Association Test (p < .05), and Digit Symbol Substitution Test (p < .001) was found. There were no significant differences in extrapyramidal symptoms. Weight gain was significantly (p = .01) greater with olanzapine.

CONCLUSIONS

Olanzapine, at higher than customary doses, demonstrated similar efficacy to clozapine in treatment-resistant schizophrenia and schizoaffective disorder in this study. However, the small sample size precludes definitively concluding that the 2 treatments are equivalent, at these doses, in treatment-resistant schizophrenia. The metabolic side effects of olanzapine are a limitation in its use.

CLINICAL TRIALS REGISTRATION

ClinicalTrials.gov identifier NCT00179231.

Effect of buspirone, a serotonin1A partial agonist, on cognitive function in schizophrenia: a randomized, double-blind, placebo-controlled study

In previous studies, we demonstrated that tandospirone, a serotonin-5-HT1A partial agonist, added to ongoing treatment with small to moderate doses of typical antipsychotic drugs, improved executive function and verbal learning and memory. However, tandospirone is not available in most countries, and atypical antipsychotic drugs (AAPDs) have largely replaced typical antipsychotic drugs as the primary treatment for schizophrenia. Therefore, the goal of this randomly assigned placebo-controlled double-blind study was to determine if the addition of buspirone, a widely available 5-HT1A partial agonist, would enhance cognitive function, in subjects with schizophrenia treated with AAPDs. Seventy-three patients with schizophrenia, who had been treated with an AAPD for at least three months, were randomly assigned to receive either buspirone, 30 mg/day, or matching placebo. All other medications remained unchanged. Attention, verbal fluency, verbal learning and memory, verbal working memory, and executive function, as well as psychopathology, were assessed at baseline, and 6 weeks, and 3 and 6 months after baseline. A significant Time x Group interaction effect was noted on the Digit Symbol Substitution Test, a measure of attention/speeded motor performance, due to better performance of the buspirone group compared to the placebo group at 3 months. No significant interaction effects were noted for other domains of cognition. Scores on the Brief Psychiatric Rating Scale (Total, Positive) were improved during treatment with buspirone but not placebo, but the effects did not reach statistical significance. The results of this study showed a possible benefit of buspirone augmentation of AAPDs to enhance attention. However, we did not replicate the results of the previous study with tandospirone, which may be due to the differences between tandospirone and buspirone, between typical antipsychotics and AAPDs, or a combination of the above. Further study to determine the usefulness of 5-HT1A agonist treatment in schizophrenia is indicated.

COMT val108/158met genotype, cognitive function, and cognitive improvement with clozapine in schizophrenia

Preliminary evidence suggests that a single nucleotide polymorphism (SNP), the val108/158met SNP, within the gene that codes for catechol-O-methyltransferase (COMT), a key enzyme involved in regulating dopamine (DA) transmission within the prefrontal cortex (PFC), is related to cognitive function in schizophrenia and cognitive improvement with atypical antipsychotic drugs (APDs). Specifically, several studies have identified an association between working memory and executive functions, and COMT val108/158met genotype in schizophrenia; although there have been several negative findings that are likely related to small sample sizes and, possibly, medication status of patients at the time of testing. The association between COMT val108/158met genotype, cognitive function, and cognitive improvement with clozapine was investigated in a relatively large prospective sample of patients with schizophrenia, most of whom were unmedicated at baseline. Patients were genotyped for the COMT val108/158met SNP after completing a cognitive battery consisting of tests of attention, working memory, verbal learning and memory, executive function, and verbal fluency at baseline and after 6 weeks and 6 months of treatment with clozapine. Consistent with several previous studies, an association between COMT genotype and tests of executive function and working memory was identified at baseline. In addition, a novel interaction between genotype and improvement on tests of attention and verbal fluency was identified. Specifically, met homozygous and val/met heterozygous patients demonstrated significantly greater improvement than val homozygous patients following 6 months of treatment with clozapine. The results are discussed in relation to previous cross-sectional studies and prospective investigations of the associations between COMT genotype, cognition, and cognitive improvement with atypical APDs in schizophrenia.

A double-blind study of combination of clozapine with risperidone in patients with schizophrenia: effects on cognition

BACKGROUND

Atypical antipsychotic drugs produce improvement in some domains of cognition as well as psychopathology in patients with schizophrenia. However, the effect of combinations of atypical antipsychotic drugs on cognitive function is unknown. The aim of this study was to compare the effect of risperidone or placebo on cognitive function in patients with schizophrenia who were previously treated with clozapine monotherapy.

METHOD

This prospective, randomized, double-blind, placebo-controlled, 6-week study included 30 patients with DSM-IV schizophrenia. Patients whose psychopathology was no more than partially responsive to clozapine treatment were randomly assigned to receive adjunctive treatment with risperidone (N = 16) up to 6 mg/day or placebo (N = 14). Cognitive test scores for verbal learning and memory, verbal fluency, attention, executive function, verbal working memory, and motor function were the primary outcome measures. Secondary outcome measures included assessment of psychopathology, extrapyramidal side effects, and global functioning. Data were collected between November 2001 and July 2003.

RESULTS

Significant improvement was found in both treatment groups in a variety of cognitive measures, but there was significantly greater improvement in the placebo-augmented group on measures of initial learning acquisition and attention. The improvement in cognition was not correlated with improvement in psychopathology. There were significant correlations between improvement in verbal working memory, verbal learning and memory, and attention and quality of life and global functioning in the placebo-augmented but not the risperidone-augmented group.

CONCLUSION

Adjunctive treatment with risperidone for 6 weeks in patients with schizophrenia who had received chronic treatment with clozapine does not significantly improve cognitive function.

Atypical antipsychotic drugs and organization of long-term semantic memory: multidimensional scaling and cluster analyses of category fluency performance in schizophrenia

Organization of semantic memory, one of the domains of cognitive function, is impaired in patients with schizophrenia, and is predictive of functional outcomes. The Category Fluency Task (CFT) has been used to evaluate organization of long-term semantic memory by means of visualizing semantic associations in the form of 'cognitive map' and cluster structures. While atypical antipsychotic drugs (AAPDs) have been shown to ameliorate overall cognitive deficits, little is known about the efficacy of AAPDs for improving higher cognitive functions, such as semantic memory organization. The purpose of the present study was to determine if treatment with olanzapine or ziprasidone has beneficial influence on organization of semantic memory, as revealed by analysis of data from the CFT, in patients with schizophrenia. A retrospective analysis of an open-label trial was conducted for 33 patients with schizophrenia who were treated with either olanzapine or ziprasidone. Nineteen subjects were unmedicated at baseline. The CFT and Letter Fluency Task, as well as the Brief Psychiatric Rating Scale (BPRS) and Quality of Life Scale (QLS), were administered at baseline and 6 wk of the treatment. Semantic structures were obtained by multidimensional scaling analysis and hierarchical cluster analysis of verbal outputs from the CFT. At baseline, no meaningful dimension or cluster was observed in the semantic structure; however, knowledge-based dimensions (wild vs. domestic) appeared after treatment with olanzapine or ziprasidone. Cluster structures also became organized, especially after treatment with olanzapine. Scores of QLS, but not those of BPRS, improved during treatment with the AAPDs. These results suggest a facilitative influence of AAPDs on higher cognitive functions, such as organization of semantic memory, in patients with schizophrenia.

Prediction of the ability of clozapine to treat negative symptoms from plasma glycine and serine levels in schizophrenia

We previously reported that plasma levels of glycine, a co-agonist at N-methyl-D-asparate (NMDA)-type glutamate receptors, are decreased in patients with schizophrenia, and that glycine levels are negatively correlated with negative symptoms. The aim of the present study was to determine if glycine, or its ratio to serine, a precursor of glycine, predicts change in negative symptoms in subjects with schizophrenia during treatment with clozapine, an atypical antipsychotic drug with multiple effects on glutamatergic activity. Plasma levels of glycine, serine, and their ratio, were measured in 44 patients with schizophrenia who were subsequently treated with clozapine. Baseline glycine levels or glycine/serine ratios predicted the Scale for the Assessment of Negative Symptoms - Sum of the Global Scales and Avolition-Apathy after 6 wk of clozapine treatment. These results indicate the association of these amino acid measures with response to clozapine in terms of negative symptoms in patients with schizophrenia.

A double-blind controlled study of adjunctive treatment with risperidone in schizophrenic patients partially responsive to clozapine: efficacy and safety

BACKGROUND

Several open trials and case studies have reported beneficial effects following the addition of risperidone for partial responders to clozapine. The purpose of this study was to carry out a placebo-controlled, randomized, double-blind trial of the efficacy, safety, and tolerability of adjunctive treatment with risperidone in patients with schizophrenia partially responsive to clozapine.

METHOD

In this 6-week double-blind study, 30 patients with DSM-IV schizophrenia who had partial response to clozapine despite being treated for a mean of 32 months were randomly assigned to risperidone (N = 16) up to 6 mg/day or placebo (N = 14). Efficacy assessments included the Positive and Negative Syndrome Scale (PANSS), the Calgary Depression Scale, the Clinical Global Impressions-Severity of Illness scale, the Global Assessment of Functioning scale, and the Quality of Life Scale. A variety of safety and tolerability measures were also obtained. Data were collected between November 2001 and July 2003.

RESULTS

Significant improvement was noted in both groups on a variety of measures of psychopathology, but there was significantly greater improvement in the placebo-treated patients on the primary outcome measure, the PANSS positive symptom subscale. There were no significant differences between the treatment groups regarding extrapyramidal symptoms, weight gain, vital signs, serum clozapine levels, and QTc interval. The only side effect significantly more severe in risperidone-treated compared to placebo-treated patients was sedation. The patients treated with risperidone developed significant increases in plasma prolactin levels.

CONCLUSION

Adjunctive risperidone treatment in schizophrenia patients partially responsive to clozapine does not significantly improve psychopathology or quality of life compared to placebo in a 6-week period.

Prediction of changes in memory performance by plasma homovanillic acid levels in clozapine-treated patients with schizophrenia

RATIONALE

Cognitive dysfunction in schizophrenia has been demonstrated to be dependent, in part, on dopaminergic activity. Clozapine has been found to improve some domains of cognition, including verbal memory, in patients with schizophrenia.

OBJECTIVES

This study tested the hypothesis that plasma homovanillic acid (pHVA) levels, a peripheral measure of central dopaminergic activity, would predict the change in memory performance in patients with schizophrenia treated with clozapine.

METHODS

Twenty-seven male patients with schizophrenia received clozapine treatment for 6 weeks. Verbal list learning (VLL)-Delayed Recall (VLL-DR), a test of secondary verbal memory, was administered before and after clozapine treatment. Blood samples to measure pHVA levels were collected at baseline.

RESULTS

Baseline pHVA levels were negatively correlated with change in performance on VLL-DR; the lower baseline pHVA level was associated with greater improvement in performance on VLL-DR during treatment with clozapine. Baseline pHVA levels in subjects who showed improvement in verbal memory during clozapine treatment ( n=13) were significantly lower than those in subjects whose memory performance did not improve ( n=14).

CONCLUSIONS

The results of this study indicate that baseline pHVA levels predict the ability of clozapine to improve memory performance in patients with schizophrenia.

The role of M1 muscarinic receptor agonism of N-desmethylclozapine in the unique clinical effects of clozapine

RATIONALE

Clozapine is a unique antipsychotic, with efficacy against positive symptoms in treatment-resistant schizophrenic patients, and the ability to improve cognition and treat the negative symptoms characteristic of this disease. Despite its unique clinical actions, no specific molecular mechanism responsible for these actions has yet been described.

OBJECTIVES AND METHODS

To comprehensively profile a large library of neuropsychiatric drugs, including most antipsychotics, at human monoamine receptors using R-SAT, an in vitro functional assay.

RESULTS

Profiling revealed that N-desmethylclozapine (NDMC), the principal metabolite of clozapine, but not clozapine itself, is a potent and efficacious muscarinic receptor agonist, a molecular property not shared by any other antipsychotic. To further explore the role of NDMC muscarinic receptor agonist properties in mediating the physiological actions of clozapine, systemically administered NDMC was found to stimulate the phosphorylation of mitogen-activated protein kinase (MAP kinase) in mouse CA1 hippocampal neurons, an effect that was blocked by scopolamine, confirming central M1 muscarinic receptor agonist activity in vivo. Lastly, an analysis of clozapine and NDMC serum levels in schizophrenic patients indicated that high NDMC/clozapine ratios better predicted improvement in cognitive functioning and quality of life than the levels of either compound alone.

CONCLUSIONS

The muscarinic receptor agonist activities of NDMC are unique among antipsychotics, and provide a possible molecular basis for the superior clinical effects of clozapine pharmacotherapy.

Cognitive effects of olanzapine treatment in schizophrenia

Improvement in some but not all domains of cognition during treatment with the atypical antipsychotic drugs clozapine, quetiapine, olanzapine, and risperidone has been reported in some but not all studies. It has been recently suggested that these reports are an artifact, related to lessening of the impairment due to typical neuroleptic drugs and anticholinergic agents. The purpose of this study was to further test the hypothesis that olanzapine, an atypical antipsychotic drug reported to have anticholinergic properties, improves cognition in patients with schizophrenia, including domains of cognition related closely to work and social function (ie, verbal learning and memory) and that this improvement is independent of improvement in psychopathology. Thirty-four patients with schizophrenia who were partial responders to typical antipsychotic drug treatment were evaluated with a comprehensive neurocognitive battery, including measures of executive functioning; verbal and visual learning and memory; working memory; immediate, selective, and sustained attention; perceptual/motor processing; and motor skills prior to and following treatment with olanzapine for 6 weeks. The Brief Psychiatric Rating Scale (BPRS) was used to assess psychopathology in patients treated with typical antipsychotic drugs. Subjects were switched to olanzapine (average dose 13.4 mg, range 5-20 mg) and reassessed following 6 weeks and 6 months of treatment. Significant improvement was noted in 9 of 19 cognitive tests, including measures of selective attention, verbal learning and memory, and verbal fluency. No cognitive test was worsened by olanzapine treatment. Improvements in the BPRS Total and Positive Symptom Subscale scores were noted. Improvements in verbal learning and memory, sustained attention, and psychomotor tracking were independent of improvement in psychopathology. These data suggest that olanzapine improved some but not all cognitive deficits in schizophrenia, including verbal memory, a cognitive domain impaired by anticholinergic drugs. The basis for the improvement in cognitive scores, which should lead to improvement in role functioning if real, is discussed.

Plasma glycine and serine levels in schizophrenia compared to normal controls and major depression: relation to negative symptoms

Previous studies have suggested decreased N-methyl-D-aspartate (NMDA)-type glutamate receptor function may contribute to increased negative symptoms in patients with schizophrenia. Consistent with this hypothesis, glycine, a co-agonist at NMDA receptors, has been reported to improve negative symptoms associated with the illness. This study was performed to determine if plasma levels of glycine or its ratio to serine, a precursor of glycine, are decreased in patients with schizophrenia compared to normal control subjects or patients with major depression. We also tested the hypothesis that these amino acids were correlated with negative symptoms in subjects with schizophrenia. Plasma levels of glycine, serine, and their ratio, were compared in 144 patients with schizophrenia, 44 patients with major depression, and 49 normal control subjects. All subjects were medication-free. Psychopathology was evaluated using the Brief Psychiatric Rating Scale (BPRS). Plasma glycine levels and glycine/serine ratios were decreased in patients with schizophrenia relative to control subjects and patients with major depression. By contrast, serine levels were increased in patients with schizophrenia compared to normal subjects but not compared to major depression. Patients with major depression also had increased plasma serine levels and decreased glycine/serine ratios compared to normal controls, but glycine levels were not different from those of normal controls. In subjects with schizophrenia, glycine levels predicted the Withdrawal-Retardation score (BPRS), whereas no such correlation was found in subjects with major depression. These results provide additional evidence that decreased availability of glycine may be related to the pathophysiology of negative symptoms. The decreases in plasma glycine levels support the evidence for an abnormality in the glutamatergic system in schizophrenia, and provide additional support for efforts to improve negative symptoms by augmentation of antipsychotic drugs with agonists at the glycine site of the NMDA receptor.

A comparison of two doses of melperone, an atypical antipsychotic drug, in the treatment of schizophrenia

Melperone at a dose of 300 mg/day has been reported to be as effective as thiothixene and superior to placebo in the treatment of schizophrenia. Limited ability to cause extrapyramidal side effects (EPS) and absence of an effect on plasma prolactin (pPRL) levels suggests that it is an atypical antipsychotic drug. The goal of this pilot study was to determine: (1). the ability of melperone 400 mg/day to produce greater improvement in psychopathology than melperone 100 mg/day; and (2). to compare side effects of these two doses of melperone. Melperone, 100 or 400 mg/day, was administered to 34 acutely hospitalized patients with schizophrenia for 6 weeks in a randomized, double-blind manner. Psychopathology, EPS, pPRL levels, and body mass index (BMI) were evaluated at baseline and 6 weeks. Twenty-seven completed the 6-week treatment. A last carried forward analysis revealed no significant difference in the ability of the two doses of melperone to improve psychopathology as measured by the Brief Psychiatric Rating Scale (BPRS)-Total and Positive subscale, the Scale for the Assessment of Negative Symptoms (SANS), the Schedule for Affective Disorders and Schizophrenia-Disorganization subscale, and the Global Assessment Scale (GAS). Treatment with melperone was not associated with exacerbation of EPS, or an increase in pPRL levels or BMI. The Abnormal Involuntary Movement Scale (AIMS) was not significantly changed by treatment with melperone. These results suggest that melperone was equally effective at doses 100 and 400 mg/day, for ameliorating psychopathology and improving overall psychiatric status in patients with schizophrenia. However, the lack of difference and a placebo control group, as well as modest degrees of change in psychopathology, require caution about assuming efficacy of either dose. The lack of significant side effects such as exacerbation of EPS, pPRL elevation, and weight gain indicates melperone is well tolerated.

Hopelessness, neurocognitive function, and insight in schizophrenia: relationship to suicidal behavior

Insight and hopelessness have been reported to be associated with suicidality in schizophrenia. In addition, there is evidence that diminished insight is correlated with impairment in some domains of cognitive function in schizophrenia. The purpose of this study was to clarify the relative importance for suicidality in patients with schizophrenia of hopelessness, cognitive dysfunction, and insight. This study included 333 patients with chronic schizophrenia who were prospectively studied. Insight was rated by the insight items from the Schedule for Affective Disorders and Schizophrenia (SADS) and the Hamilton Depression Rating Scale (HDRS). Positive, negative, and anxiety-depression symptoms were measured with the Brief Psychiatric Rating Scale (BPRS). Cognition was assessed with a neurocognitive battery, which included measures of attention and psychomotor speed, verbal fluency, verbal memory, working memory, and executive function. Current and lifetime suicidality was prospectively assessed. Hopelessness, substance abuse, and greater insight were associated with attempted suicide and suicidal ideation. Those with a history of lifetime, but not current, suicidality had better function on tests of psychomotor speed and attention, verbal working memory, verbal fluency, verbal memory, and executive function. Neurocognitive measures were not significantly correlated with hopelessness and insight. Hopelessness was more severe in those with current and lifetime suicidality. A multiple regression analysis was used to predict current and lifetime suicidality from hopelessness, substance abuse, insight, and cognitive factor scores. The regression models predicting current and lifetime suicidality indicated that hopelessness was the most important predictor of both (beta=0.41, p=0.0001; and beta=0.35, p=0.01, respectively). These findings suggest that hopelessness, substance abuse, greater insight into illness, and higher cognitive function are associated with greater suicidality in chronic schizophrenia, but that among these, hopelessness may be the principal predictor of suicidality.

H1-histamine receptor affinity predicts short-term weight gain for typical and atypical antipsychotic drugs

As a result of superior efficacy and overall tolerability, atypical antipsychotic drugs have become the treatment of choice for schizophrenia and related disorders, despite their side effects. Weight gain is a common and potentially serious complication of some antipsychotic drug therapy, and may be accompanied by hyperlipidemia, hypertension and hyperglycemia and, in some extreme cases, diabetic ketoacidosis. The molecular mechanism(s) responsible for antipsychotic drug-induced weight gain are unknown, but have been hypothesized to be because of interactions of antipsychotic drugs with several neurotransmitter receptors, including 5-HT(2A) and 5-HT(2C) serotonin receptors, H(1)-histamine receptors, alpha(1)- and alpha(2)-adrenergic receptors, and m3-muscarinic receptors. To determine the receptor(s) likely to be responsible for antipsychotic-drug-induced weight gain, we screened 17 typical and atypical antipsychotic drugs for binding to 12 neurotransmitter receptors. H(1)-histamine receptor affinities for this group of typical and atypical antipsychotic drugs were significantly correlated with weight gain (Spearman rho=-0.72; p<0.01), as were affinities for alpha(1A) adrenergic (rho=-0.54; p<0.05), 5-HT(2C) (rho=-0.49; p<0.05) and 5-HT(6) receptors (rho=-0.54; p<0.05), whereas eight other receptors' affinities were not. A principal components analysis showed that affinities at the H(1), alpha(2A), alpha(2B), 5-HT(2A), 5-HT(2C), and 5-HT(6) receptors were most highly correlated with the first principal component, and affinities for the D(2), 5-HT(1A), and 5-HT(7) receptors were most highly correlated with the second principal component. A discriminant functions analysis showed that affinities for the H(1) and alpha(1A) receptors were most highly correlated with the discriminant function axis. The discriminant function analysis, as well as the affinity for the H(1)-histamine receptor alone, correctly classified 15 of the 17 drugs into two groups; those that induce weight gain and those that do not. Because centrally acting H(1)-histamine receptor antagonists are known to induce weight gain with chronic use, and because H(1)-histamine receptor affinities are positively correlated with weight gain among typical and atypical antipsychotic drugs, it is recommended that the next generation of atypical antipsychotic drugs be screened to avoid H(1)-histamine receptors.

The effect of melperone, an atypical antipsychotic drug, on cognitive function in schizophrenia

Melperone, a butyrophenone, has been shown to possess atypical antipsychotic properties, i.e. ability to produce an antipsychotic effect in man at doses that cause minimal extrapyramidal side effects. In addition, melperone shares the following with other atypical antipsychotic drugs: (1) effectiveness for ameliorating negative symptoms; (2) no prolactin elevation; and (3) effectiveness in the treatment of some patients with neuroleptic-resistant schizophrenia. Other atypical antipsychotic drugs have been reported to improve cognitive function. This study was performed to investigate the effect of melperone on cognitive function. Nineteen patients with schizophrenia or schizoaffective disorder, including 11 neuroleptic-resistant patients, were treated with melperone for 6 weeks. A comprehensive neurocognitive test battery and psychopathological ratings (Brief Psychiatric Rating Scale, BPRS) were administered at baseline and after 6 weeks of melperone treatment. Treatment with melperone was associated with improvement in executive function, as measured by the Wisconsin Card Sorting Test (WCST)-Categories and WCST-Percent Perseveration. On the other hand, visuospatial manipulation, as measured by the Wechsler Intelligent Scale for Children-Revised (WISC-R) Maze, worsened during melperone treatment. There were no significant changes in other domains of cognition, i.e. verbal learning and memory, verbal working memory, verbal fluency and sustained attention. Scores of WCST-Categories and Perseveration at 6 weeks were predicted from the relevant cognitive test scores at baseline and the change in BPRS Total and Positive scores. These results suggest the usefulness of melperone for facilitating work and social function in patients with schizophrenia. The differences in the cognition-enhancing abilities between melperone and clozapine are discussed.

Melperone in the treatment of neuroleptic-resistant schizophrenia

Melperone is an effective antipsychotic drug that has been reported to have atypical properties, i.e. low extrapyramidal side effect liability at clinically effective doses. It also does not increase serum prolactin levels. Its effectiveness for patients with neuroleptic (treatment)-resistant schizophrenia has not been evaluated. In this study, melperone was administered, in an open trial design of 6 weeks' duration, to 44 patients with chronic neuroleptic-resistant schizophrenia. The Global Assessment Scale (GAS), Brief Psychiatric Rating Scale (BPRS) and measures of extrapyramidal symptoms and other clinical variables were assessed at baseline and 6 weeks. Thirty-seven patients completed the 6-week trial. Melperone significantly improved overall psychiatric status as measured by GAS score for all evaluable subjects [last value carried forward (LVCF) and a completers analysis]. No significant effects on BPRS measures of psychopathology scores were found in the LVCF or completers analysis. Patients who showed > or = 20% decrease in the BPRS Total score (N=7) were more likely to have high baseline psychopathology, as measured by BPRS Total and Anxiety-Depression subscales, than those who showed > or = 20% increase in the BPRS Total score (N=8). Non-responders to melperone generally did not respond to subsequent treatment with clozapine, indicating that this group of patients was very treatment resistant. Melperone was not associated with worsening of extrapyramidal symptoms, elevation in plasma prolactin levels, or an increase in body mass index (BMI). The results suggest that a proportion of neuroleptic-resistant patients with schizophrenia respond to melperone, which requires further controlled study.

Enhancement of cognitive performance in schizophrenia by addition of tandospirone to neuroleptic treatment

OBJECTIVE

The goal of this study was to evaluate the effects of the addition of tandospirone, a serotonin-1A (5-HT(1A)) agonist, to ongoing treatment with typical antipsychotic drugs, on two cognitive domains that are relevant to functional outcome in patients with schizophrenia.

METHOD

Twenty-six patients with schizophrenia who were receiving stable doses of typical antipsychotics were randomly assigned to adjunctive treatment with 30 mg/day of tandospirone or placebo for 6 weeks. Executive function and verbal memory as well as psychopathology were assessed at baseline and after 6 weeks.

RESULTS

Both cognitive measures improved significantly in the patients who received tandospirone; subjects who did not receive tandospirone showed no change. There was no significant change in psychopathology ratings in either group.

CONCLUSIONS

The results suggest the usefulness of 5-HT(1A) agonists for enhancing some types of cognitive performance and possibly social and work function in patients with schizophrenia.

The blunted plasma cortisol response to apomorphine and its relationship to treatment response in patients with schizophrenia

The adrenocorticotropic hormone (ACTH) and cortisol responses to apomorphine (APO), a direct acting dopamine (DA) agonist, have been reported to be significantly blunted in neuroleptic-free patients with schizophrenia (SCH). This study primarily examined the cortisol, but also the prolactin (PRL) and growth hormone (GH), response to APO in patients with SCH compared to normal controls, as well as the relationship between endocrine measures and response to antipsychotic drug treatment. APO, 0.01 mg/kg, or placebo was administered to 51-98 patients with SCH and 15-25 normal controls. Psychopathology was assessed at the baseline and six weeks after drug treatment. The plasma cortisol response to APO was markedly blunted in patients with SCH compared to normal controls. Patients who responded to six weeks of treatment with antipsychotic drugs had a higher cortisol response to APO compared to non-responders. The plasma GH, but not PRL, response to APO was blunted in male patients with SCH. Neither plasma GH nor PRL responses to APO were related to treatment response at six weeks. These results provide further evidence of dopaminergic dysfunction in SCH. Furthermore, the APO-stimulated cortisol response may be predictive of subsequent clinical response to antipsychotic drug treatment.

Low-dose loxapine in the treatment of schizophrenia: is it more effective and more "atypical" than standard-dose loxapine?

Loxapine is chemically related to clozapine and shares with it and other atypical antipsychotic drugs relatively greater affinity for serotonin (5-HT)2A than for dopamine D2 receptors. However, as is the case for risperidone, the occupancy of 5-HT2A and D2 receptors can range from partial to full, depending upon the dose. It was, therefore, of interest to determine whether loxapine at low doses (< 50 mg/day) might be at least as or more effective and more tolerable than usual clinical doses (> or = 60 mg/day). We retrospectively examined data from 75 patients treated with loxapine and found psychopathology data from 10 and 12 patients treated with low-dose or standard-dose loxapine, respectively. No data were available on the other 53 patients, 28 of whom were initially treated with low-dose and 25 with standard-dose loxapine. For those treated for at least 6 weeks, there was evidence of equivalent efficacy for both low- and standard-dose loxapine with regard to improvement in Brief Psychiatric Rating Scale (BPRS) and Global Assessment Scale scores. There were 6 patients with a history of neuroleptic resistance among the 22 completers. Four of the low-dose group (40%) and 8 of the standard-dose group (67%) had at least a 20% decrease in BPRS total scores. Further study of the dose-response curve for loxapine and its usefulness in treating neuroleptic-resistant schizophrenia is indicated.

A comparison of the effect of clozapine with typical neuroleptics on cognitive function in neuroleptic-responsive schizophrenia

Clozapine has been reported to improve selected aspects of cognitive function in neuroleptic-resistant schizophrenia. In this study, we report the first direct comparison of the effect of clozapine and typical neuroleptic drugs on cognitive function in neuroleptic-responsive schizophrenia. Sixty-four patients with recent onset, neuroleptic-responsive schizophrenia or schizoaffective disorder were randomly assigned to either clozapine (n = 35) or typical neuroleptics (n = 29) and followed for 12 months. They were administered a comprehensive cognitive test battery at baseline and at 6 weeks, 6 months and 12 months after initiating drug treatment. Treatment with clozapine improved psychomotor speed and attention [Digit Symbol Substitution Test (DSST)] and verbal fluency [Category Instance Generation and Controlled Word Association Test (CWAT)] at 6 weeks. The improvement in these measures was maintained throughout the 12-month period. Treatment with typical neuroleptics produced no sustained improvement in any cognitive measure, except for a tendency to improve delayed recall memory (Verbal List Learning Test). The improvement in the DSST and CWAT was significantly greater with clozapine treatment compared to that with typical neuroleptics. These improvements were not related to improvement in psychopathology. These results suggest that clozapine is superior to typical neuroleptics in improving specific types of cognitive function in recent onset, neuroleptic-responsive schizophrenia.

Effects of subchronic treatment with valproate on L-5-HTP-induced cortisol responses in mania: evidence for increased central serotonergic neurotransmission

The mechanisms underlying the acute and prophylactic antimanic properties of valproate have remained elusive. There are some reports that treatment with valproic acid may increase brain serotonergic neurotransmission in the rodent. This study was carried out in order to investigate the effects of subchronic therapy with valproate on central serotonin metabolism in manic patients. Toward this end, the authors examined plasma cortisol responses to 200 mg (orally) L-5-hydroxy-tryptophan (L-5-HTP) in 10 manic patients both before and after subchronic treatment with valproate. Administration of L-5-HTP resulted in significantly increased cortisol responses both before and after treatment with valproate. The L-5-HTP-induced cortisol responses were significantly higher after treatment with valproate than before treatment. It is suggested that valproate may increase central serotonergic neurotransmission and that this stimulation may play a role in the antimanic effects of valproate.