Independent effects of tobacco abstinence and bupropion on cognitive function in schizophrenia

OBJECTIVE: The objective of this study was to examine the effects of tobacco abstinence and bupropion treatment on cognitive functioning in adult smokers with schizophrenia in the setting of a randomized, double-blind, placebo-controlled clinical trial of bupropion for smoking cessation. METHOD: Fifty-three adults with schizophrenia (DSM-IV) took part in a trial of bupropion for smoking cessation. Subjects were enrolled in the study from August 1999 to March 2003. Forty-five subjects remained in the trial at week 4; 41 subjects, 19 taking bupropion and 22 taking placebo, completed the baseline and week 4 cognitive assessments and were included in the analysis of adjusted effects of abstinence and bupropion treatment on cognitive function. RESULTS: Controlling for bupropion treatment and baseline performance, 7 days of tobacco abstinence was associated with slowed motor speed (finger tapping) but was not associated with worsening of performance on tests of attention (AX Continuous Performance Test [AX-CPT]), verbal learning and memory (California Verbal Learning Test [CVLT]), working memory (digit span), or executive function/inhibition (Stroop) and was not associated with worsening of any clinical measures. Controlling for abstinence status, bupropion was associated with reduction (improvement) in reaction time variability on the AX-CPT and with reduction in perseverative errors on the CVLT. CONCLUSION: We conclude that 1 week of tobacco abstinence is associated with slowed motor speed but is not associated with detectable worsening in performance on a range of neuropsychological tests or clinical symptoms in the subset of patients who were able to quit smoking. We also conclude that bupropion treatment may be associated with improvement in variability of attention.     

Analysis of the autism chromosome 2 linkage region: GAD1 and other candidate genes

Autism has a strong and complex genetic component, involving several genes. Genomic screens, including our own, have shown suggestive evidence for linkage over a 20-30 cM region on chromosome 2q31-q33. Two subsequent reports showed that the linkage evidence increased in the subset of families with phrase speech delay (PSD), defined as onset of phrase speech later than 3 years of age. To further investigate the linkage in the presumptive candidate region, microsatellite markers in a 2 cM grid covering the interval from 164 to 203 cM were analyzed in 110 multiplex (2 or more sampled autism patients) families. A maximum heterogeneity LOD (HLOD) score of 1.54 was detected at D2S1776 (173 cM) in the overall dataset (dominant model), increasing to 1.71 in the PSD subset. While not conclusive, these data continue to provide suggestive evidence for linkage, particularly considering replication by multiple independent groups. Positive LOD scores extended over the entire region, continuing to define a broad candidate interval. Association studies were performed on several functional candidates mapping within the region. These included GAD1, encoding GAD67, whose levels are reduced in autopsy brain material from autistic subjects, and STK17B, ABI2, CTLA4, CD28, NEUROD1, PDE1A, HOXD1 and DLX2. We found no evidence for significant allelic association between autism and any of these candidates, suggesting that they do not play a major role in the genetics of autism or that substantial allelic heterogeneity at any one of these loci dilutes potential disease-allele association.     

Two-year follow-up of a smoking cessation trial in patients with schizophrenia: increased rates of smoking cessation and reduction

BACKGROUND: Long-term success rates of smoking cessation programs for patients with schizophrenia are unknown. This study, conducted between June 2001 and November 2002, evaluated the rate of smoking cessation and reduction in patients with schizophrenia (DSM-IV) 2 years after they had participated in a smoking cessation study in order to determine whether subjects who significantly reduced smoking during the original trial resumed their previous level of smoking at 2 years. METHOD: Two years following a double-blind placebo-controlled trial of bupropion sustained release, 150 mg/day, added to cognitive-behavioral therapy for smoking cessation in patients with schizophrenia, subjects were interviewed, medical charts were reviewed, and carbon monoxide in expired air was measured. RESULTS: Seventeen of 18 subjects completed the follow-up assessment. More subjects were abstinent (22% [N = 4]) at the 2-year follow-up than were abstinent at the end of the trial (6% [N = 1]). Subjects who achieved significant smoking reduction during the trial were more likely to be abstinent at 2 years (4/7) than those who did not significantly reduce smoking during the trial (0/11) (chi(2) = 8.1, p <.005). Most subjects who achieved > or = 50% reduction in smoking at the end of the trial maintained at least that level of reduction at 2 years. Smoking reduction during the treatment intervention was correlated with smoking reduction at follow-up (r = 0.60, p =.01). CONCLUSION: The results from this naturalistic study suggest that behavior changes achieved in smoking cessation programs for patients with schizophrenia may be durable and may predict future smoking behavior. We conclude that further investigation into the relationship between smoking reduction and future smoking cessation in special populations is indicated.     

Attitudes of schizophrenia outpatients toward psychiatric medications: relationship to clinical variables and insight

BACKGROUND: Attitude toward medications is important for medication adherence. A patient's drug attitude probably reflects a weighing of benefits against experienced or anticipated side effects or risks associated with the medication. We predicted (1) that drug attitudes would be more positive among schizophrenia patients taking second-generation compared to first-generation antipsychotics because of their greater tolerability and efficacy; and (2) that greater insight into illness, fewer extrapyramidal symptoms, and better social functioning would be associated with better attitudes toward psychiatric medication. METHOD: In a cross-sectional study of 81 DSM-IV-diagnosed schizophrenia outpatients, we used multivariate analysis to determine clinical and demographic predictors of drug attitude. Drug attitude was assessed with the 10-item Drug Attitude Inventory (DAI). The relationship between the DAI and psychopathology, insight, extrapyramidal symptoms, level of functioning, and type of antipsychotic (first-generation versus second-generation versus clozapine) was examined. RESULTS: Less awareness of current symptoms, presence of deficit symptoms, and employment predicted a negative attitude toward psychiatric medications. Extrapyramidal symptoms did not predict drug attitude. Drug attitudes were no different between patients taking first- or second-generation antipsychotics or clozapine. CONCLUSION: Patients may not favor second-generation over first-generation antipsychotics, and extrapyramidal symptoms may not be a primary factor determining attitudes. While attitudes may be more positive in patients who recognize therapeutic drug effects, patients who work may view medications particularly negatively, possibly due to a sense of stigma. Because drug attitudes may reflect compliance and are difficult to predict, clinicians should inquire directly.     

Comprehensive association analysis of APOE regulatory region polymorphisms in Alzheimer disease

Several recent case-control studies have examined the association between single nucleotide polymorphisms (SNPs) in the promoter region of the apolipoprotein E gene (APOE) and risk of Alzheimer disease (AD), with conflicting results. We assessed the relation between five APOE region SNPs and risk of AD in both case-control and family-based analyses. We observed a statistically significant association with the +5361T allele in the overall case-control analysis (P value=0.04) after adjusting for the known effect of the APOE-4 allele. Further analysis revealed this association to be limited to carriers of the APOE-4 allele. Age-stratified analyses in the patients with age at onset of 80 years or greater and age-matched controls showed that the –219T allele (P value=0.009) and the +113C allele (P value=0.03) are associated with increased risk of AD. Despite these findings, haplotype and family-based association analyses were unable to provide evidence that the APOE region SNPs influenced risk of AD independent of the APOE-4 allele. In addition to risk, we tested for association between the SNPs and age at onset of AD, but found no association in the case-control or family based analyses. In conclusion, SNPs +5361, or a SNP in strong linkage disequilibrium, may confer some additional risk for developing AD beyond the risk due to APOE-4; however, the effect independent of APOE-4 is likely to be small.     

The problem of the placebo response in clinical trials for psychiatric disorders: culprits,possible remedies,and a novel study design approach

The placebo response is a major issue in clinical trials for psychiatric disorders. Possible contributing factors to this problem include diagnostic misclassification, issues concerning inclusion/exclusion criteria, outcome measures' lack of sensitivity to change, measurement errors, poor quality of data entry and verification, waxing and waning of the natural course of illness, regression toward the mean phenomenon, patient and clinician expectations about the trial, study design issues, non-specific therapeutic effects, and high attrition. Over the past few decades, researchers have attempted to reduce the placebo effect in a variety of ways. Unfortunately, approaches with very little or no benefit have included restricting enrollment to selected populations, rater training, requirement of same rater, and placebo lead-in phases. Some benefits, although often marginal, have been derived from standardizing diagnostic procedures, managing clinicians' overestimation of change, simplification of study visits and assessments, minimizing non-specific, therapeutic effects, extending trial duration, reducing number of sites, increasing the sensitivity of outcome measures, and reducing the number of treatment arms. Thus far, there has been no attempt to develop new study designs aimed at reducing the placebo effect. We are proposing a novel study design, called 'Sequential Parallel Comparison Design', suitable for double-blind, placebo-controlled trials in psychiatric disorders. This design is aimed at reducing both the overall placebo response rate and the sample size required for such trials. Its usefulness in clinical research needs to be tested empirically. If this study design were to be found to meet its stated goals, this could markedly facilitate the process of clinical development of new compounds for the treatment of psychiatric disorders.     

Association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia

AIMS: To investigate the association of acute parvovirus B19 infection with new onset of acute lymphoblastic and myeloblastic leukaemia. METHODS: Cerebrospinal fluid (CSF) samples from patients with acute myelogenous leukaemia (AML) at diagnosis (n = 2) and acute lymphoblastic leukaemia (ALL) at diagnosis (n = 14) were analysed for parvovirus B19 DNA by means of nested polymerase chain reaction. In addition, samples from patients with benign intracranial hypertension (BIH) (n = 10) and hydrocephalus (n = 13) were tested as controls. RESULTS: Four leukaemia cases were positive-common ALL (n = 2), null cell ALL (n =1), and M7 AML (n = 1)-whereas all controls were negative (Yates corrected chi(2) value, 3.97; p = 0.046; odds ratio, 16.92; confidence interval, 1.03 to 77.18). All four patients were significantly anaemic, but none was encephalitic or had evidence of central nervous system leukaemia. In three of these patients, serum tumour necrosis alpha, interferon gamma, interleukin 6, granulocyte-macrophage colony stimulating factor (range, 34.93-3800.06 pg/ml), and macrophage chemoattractant protein 1 were detectable. All of these four patients carried at least one of the HLA-DRB1 alleles, which have been associated with symptomatic parvovirus B19 infection. CONCLUSION: Erythroid suppression and immune cell proliferation are both associated with B19 infection and may also be important in the pathogenesis of acute leukaemia.