1Schizophr. Res. 2002 Nov 58: 21-30
PMID12363386
TitleDecreased calcium-dependent constitutive nitric oxide synthase (cNOS) activity in prefrontal cortex in schizophrenia and depression.
AbstractTo further understand the potential role of nitric oxide synthase (NOS) in schizophrenia and affective disorders, we determined the calcium-dependent constitutive NOS (cNOS) enzymatic activity and protein levels in the prefrontal cortex of postmortem brains of patients with unipolar, bipolar, and schizophrenic disorders and non-psychiatric controls (n = 15 for each group). Protein levels of two NOS isoforms, nNOS and eNOS, were not significantly different from the non-psychiatric controls in any of the patient groups. However, cNOS activity was significantly lower in schizophrenic patients (mean +/- S.E. = 19.1 +/- 3.2 CPM/microg/45 min) than in the control group (28.5 +/- 3.4, P < 0.05). Trends of lower cNOS activity were found in unipolar (20.3 +/- 2.6, P = 0.062) and bipolar patients (20.8 +/- 3.0, P = 0.079). Males had significantly higher NOS activity (25.4 +/- 2, n = 36, P = 0.01) than females (17.3 +/- 1.9, n = 24), but no significant diagnosis and gender interactions were found. To minimize potential effects of extended postmortem interval (PMI) on NOS activity and proteins, the PMI was limited to 30 h and the data (n = 38) were re-analyzed. cNOS activity was significantly (P < 0.05) lower in patients with schizophrenia (15.8 +/- 5.6, P = 0.026) and unipolar depression (18.8 +/- 3.2, P = 0.042) but not in patients with bipolar illness (22.9 +/- 3.4, P = 0.21) than in the control group (29.5 +/- 3.7). cNOS activity was significantly correlated with brain pH in the total sample (r = 0.28, P < 0.05, n = 60) and in the PMI controlled subgroup (r = 0.43, P < 0.01, n = 38). Our data provide evidence of reduced cNOS activity in the postmortem brains of patients with schizophrenia and depression.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal
2Schizophr. Res. 2002 Nov 58: 21-30
PMID12363386
TitleDecreased calcium-dependent constitutive nitric oxide synthase (cNOS) activity in prefrontal cortex in schizophrenia and depression.
AbstractTo further understand the potential role of nitric oxide synthase (NOS) in schizophrenia and affective disorders, we determined the calcium-dependent constitutive NOS (cNOS) enzymatic activity and protein levels in the prefrontal cortex of postmortem brains of patients with unipolar, bipolar, and schizophrenic disorders and non-psychiatric controls (n = 15 for each group). Protein levels of two NOS isoforms, nNOS and eNOS, were not significantly different from the non-psychiatric controls in any of the patient groups. However, cNOS activity was significantly lower in schizophrenic patients (mean +/- S.E. = 19.1 +/- 3.2 CPM/microg/45 min) than in the control group (28.5 +/- 3.4, P < 0.05). Trends of lower cNOS activity were found in unipolar (20.3 +/- 2.6, P = 0.062) and bipolar patients (20.8 +/- 3.0, P = 0.079). Males had significantly higher NOS activity (25.4 +/- 2, n = 36, P = 0.01) than females (17.3 +/- 1.9, n = 24), but no significant diagnosis and gender interactions were found. To minimize potential effects of extended postmortem interval (PMI) on NOS activity and proteins, the PMI was limited to 30 h and the data (n = 38) were re-analyzed. cNOS activity was significantly (P < 0.05) lower in patients with schizophrenia (15.8 +/- 5.6, P = 0.026) and unipolar depression (18.8 +/- 3.2, P = 0.042) but not in patients with bipolar illness (22.9 +/- 3.4, P = 0.21) than in the control group (29.5 +/- 3.7). cNOS activity was significantly correlated with brain pH in the total sample (r = 0.28, P < 0.05, n = 60) and in the PMI controlled subgroup (r = 0.43, P < 0.01, n = 38). Our data provide evidence of reduced cNOS activity in the postmortem brains of patients with schizophrenia and depression.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal
3J Clin Psychiatry 2004 May 65: 679-85
PMID15163255
TitlePatterns of concomitant psychotropic medication use during a 2-year study comparing clozapine and olanzapine for the prevention of suicidal behavior.
AbstractResults from the International Suicide Prevention Trial (InterSePT) indicate that clozapine is more effective than olanzapine in reducing suicidal behavior in schizophrenic and schizoaffective patients. However, because InterSePT allowed the uncontrolled use of concomitant psychotropic medications (CPMs), it is possible that the antisuicidal effect of clozapine may have been influenced by greater use of such agents. This article describes the use patterns of CPMs during InterSePT and examines whether CPM use may have affected study outcome.
In this study, 479 patients received clozapine and 477 patients received olanzapine. Concomitant psychotropic medications were grouped into 4 classes: antipsychotics, antidepressants, sedatives/anxiolytics, and mood stabilizers. The doses of each CPM were converted into dosage equivalents of standard reference drugs. An analysis of covariance was performed to compare mean daily doses of CPMs between the 2 groups over the 2-year treatment period. The duration of treatment for each patient was 2 years, with the first patient entering the study in March 1998 and the last patient completing treatment in February 2001.
Approximately 90% of patients in both treatment groups received at least 1 CPM. The mean +/- SD number of CPMs per patient was 3.8 +/- 2.90 in the clozapine group and 4.2 +/- 3.16 in the olanzapine group. For each CPM class, the mean daily dose was statistically significantly lower in the clozapine group (antipsychotics, p <.001; antidepressants, p <.01; sedatives/anxiolytics, p <.001; mood stabilizers, p <.05). Analyses of CPM use by study intervals, suicide attempters versus nonattempters, study completers versus noncompleters, and geographic region resulted in similar findings.
The results support the conclusion that the effects of clozapine in reducing the risk of suicidal behavior derive from its intrinsic pharmacology and not from the influence of concomitant psychotropic medications.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal
4J Clin Psychiatry 2006 Aug 67: 1261-5
PMID16965205
TitleConcomitant medications may not improve outcome of antipsychotic monotherapy for stabilized patients with nonacute schizophrenia.
AbstractThere are virtually no controlled data suggesting that concomitant psychotropic medications (CPMs) improve outcome in schizophrenia after the acute phase. Despite that, polypharmacy (with all of its disadvantages) is far more common than monotherapy. To our knowledge, there have been no published reports of prospective systematic investigations of the efficacy of unrestricted CPM use in nonacute schizophrenia.
This was a naturalistic, systematic study using a sample of 53 stabilized patients with DSM-IV-TR schizophrenia from 1 clinical practice setting including both private patients and patients from controlled research studies of the effectiveness of antipsychotics. Since there are meager controlled or systematic data on the effectiveness of CPM use with antipsychotics in nonacute schizophrenia, we tested the clinical strategy of CPM use by gradually tapering all CPMs (except antianxiety agents). The aim was to determine if the CPM improved outcome, had no effect, or worsened outcome using the Clinical Global Impressions-Improvement scale before and after taper, over at least 3 months and in some cases up to 18 months after discontinuation. Data were gathered from July 2002 to June 2005.
For 21 patients undergoing 22 antidepressant tapers, no change was noted in 18 of 22 tapers, while in 3 improvement was noted and in 1 worsening was noted. For the 12 patients on treatment with mood stabilizers, no change was noted in 10 of 13 discontinuations, while in 3 mild worsening was noted. One patient was on treatment with both modafinil and trazodone and reported no change after tapering each in separate discontinuation trials, while another 3 patients were taking sleeping medications and also noted no change after discontinuation.
For most stabilized, chronic patients with schizophrenia, tapering adjunctive medications did not change outcome. This naturalistic study further defines the limits of efficacy of some concomitant classes of medications in patients with chronic schizophrenia who are already receiving adequate antipsychotic therapy.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal
5Multivariate Behav Res 2011 Nov 46: 900-37
PMID26736117
TitleComparison of Modern Methods for Analyzing Repeated Measures Data With Missing Values.
AbstractMissing data are a pervasive problem in many psychological applications in the real world. In this article we study the impact of dropout on the operational characteristics of several approaches that can be easily implemented with commercially available software. These approaches include the covariance pattern model based on an unstructured covariance matrix (CPM-U) and the true covariance matrix (CPM-T), multiple imputation-based generalized estimating equations (MI-GEE), and weighted generalized estimating equations (WGEE). Under the missing at random mechanism, the MI-GEE approach was always robust. The CPM-T and CPM-U methods were also able to control the error rates provided that certain minimum sample size requirements were met, whereas the WGEE was more prone to inflated error rates. In contrast, under the missing not at random mechanism, all evaluated approaches were generally invalid. Our results also indicate that the CPM methods were more powerful than the MI-GEE and WGEE methods and their superiority was often substantial. Furthermore, we note that little or no power was sacrificed by using CPM-U method in place of CPM-T, although both methods have less power in situations where some participants have incomplete data. Some aspects of the CPM-U and MI-GEE methods are illustrated using real data from 2 previously published data sets. The first data set comes from a randomized study of AIDS patients with advanced immune suppression, the second from a cohort of patients with schizotypal personality disorder enrolled in a prevention program for psychosis.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal
6Neuropsychiatr Dis Treat 2012 -1 8: 49-54
PMID22347796
TitleA case of mistaken identity: alcohol withdrawal, schizophrenia, or central pontine myelinolysis?
AbstractDemyelination is a hallmark of central pontine myelinolysis (CPM). Neuropsychiatric manifestations of this condition include weakness, quadriplegia, pseudobulbar palsy, mood changes, psychosis, and cognitive disturbances. These psychiatric symptoms are also associated with schizophrenia and alcohol withdrawal. Thus, it is clinically relevant to differentiate between CPM, schizophrenia, and alcohol withdrawal as the treatment and prognostic outcomes for each diagnosis are distinct. We present a series of events that led to a misdiagnosis of a patient admitted to the medical emergency center presenting with confusion, psychomotor agitation, and delirium who was first diagnosed with schizophrenia and alcohol withdrawal by emergency medical physicians and later discovered by the psychiatric consult team to have CPM. With a thorough psychiatric evaluation, a review of the laboratory results first showing mild hyponatremia (127 mmol/L), subsequent hypernatremia (154 mmol/L), and magnetic resonance brain imaging, psychiatrists concluded that CPM was the primary diagnosis underlying the observed neuropsychopathology. This patient has mild impairments in mood, cognition, and motor skills that remain 12 months after her emergency-center admission. This case report reminds emergency clinicians that abnormal sodium metabolism can have long-term and devastating psychopathological and neurological consequences. Differentiating between CPM, schizophrenia, and alcohol withdrawal using neuroimaging techniques and preventing the risks for CPM using slow sodium correction are paramount.
SCZ Keywordsschizophrenia, schizophrenic, schizotypal