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.

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.

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.

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.

Fluoxetine, but not tricyclic antidepressants, potentiates the 5-hydroxytryptophan-mediated increase in plasma cortisol and prolactin secretion in subjects with major depression or with obsessive compulsive disorder

It has been suggested that the clinical efficacy of chronic treatment with selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine and perhaps all antidepressants is due to their ability to enhance serotonergic activity. The effects of chronic treatment with fluoxetine or tricyclic antidepressants on the L-5-hydroxytryptophan (200 mg, L-5-HTP; PO)-induced increases in plasma cortisol and prolactin (PRL) concentrations were studied in patients with major depression or obsessive compulsive disorder (OCD). Administration of L-5-HTP increased plasma cortisol and PRL levels in medicated and unmedicated patients with major depression or OCD. The L-5-HTP-induced cortisol and PRL responses were significantly higher in fluoxetine-treated than in tricyclic-treated or unmedicated major depressed patients. The latter two groups did not differ significantly in their cortisol or PRL responses to L-5-HTP. The L-5-HTP-induced increases in cortisol and PRL in fluoxetine-treated patients with major depression or OCD were not significantly different. The results suggest that fluoxetine, but not tricyclic antidepressants, potentiates 5-HT receptor-mediated stimulation of cortisol and PRL secretion in humans, consistent with available evidence that fluoxetine treatment, but not tricyclic antidepressants, increases central serotonergic activity in patients with MD or OCD by a presynaptic mechanism.

Prediction of short-term changes in symptom severity by baseline plasma homovanillic acid levels in schizophrenic patients receiving clozapine

The relationship between pretreatment levels of plasma homovanillic acid (pHVA) and the outcome of clozapine treatment was studied in 18 male patients with schizophrenia who were resistant to treatment with conventional neuroleptics. After 6 months of clozapine treatment, 7 patients demonstrated > or = 20% decrease in the Brief Psychiatric Rating Scale (BPRS) (responders), while 11 patients did not (non-responders). Responders and non-responders did not differ with respect to the baseline pHVA level. The BPRS Positive Symptom scores at 6 weeks and 3 months, but not those at baseline and 6 months, following initiation of clozapine treatment negatively correlated with pHVA levels for all patients. The correlations became stronger when only responders were included. No significant correlation between Positive Symptom scores and pHVA levels was observed for non-responders. The BPRS Total and Negative Symptom scores did not correlate with pHVA for all patients, responders or non-responders at any time. The percent decrease in the BPRS Positive Symptom scores from baseline at 6 weeks following clozapine treatment correlated significantly with pHVA levels in responders. These results suggest that pretreatment levels of pHVA can be used to predict relatively short-term changes in the positive symptoms of patients with schizophrenia receiving clozapine treatment, particularly for clozapine responders.

Sex differences in plasma homovanillic acid levels in schizophrenia and normal controls: relation to neuroleptic resistance

Plasma homovanillic acid (pHVA) levels were compared in a large number of neuroleptic-resistant and -responsive schizophrenic patients (male/female = 161/46) and normal controls (67/27), and correlated with various measures of psychopathology. Psychopathology was evaluated with the brief psychiatric rating scale, the Schedule for Affective Disorders and Schizophrenia-Change version (SADS-C) and SADS-C Global Assessment Scale, the Scale for Assessment of Negative Symptoms, the Scale for Assessment of Positive Symptoms (SAPS), and the Quality of Life Scale. No significant differences in pHVA levels between neuroleptic-resistant (n = 104) or -responsive (n = 103) schizophrenic patients, and normal controls, were found; however, there was a main effect for sex, due to higher pHVA levels in women than men. There were no diagnosis x gender or age effects on pHVA levels. No significant correlations were observed between psychopathology ratings and baseline pHVA levels, except with the Hallucinations subscale of SAPS in neuroleptic-responsive patients. Neither duration of neuroleptic washout nor plasma prolactin levels correlated with pHVA levels. Further studies on the origin and significance of the gender difference in pHVA are indicated.

Pre-morbid asociality in neuroleptic-resistant and neuroleptic-responsive schizophrenia

The purpose of this study was to evaluate whether childhood and adolescent pre-morbid asociality differed in neuroleptic-responsive and neuroleptic-resistant schizophrenia. Pre-morbid asociality was assessed with the Pre-morbid Asociality Adjustment Scale in 411 patients meeting DSM-III-R criteria for chronic schizophrenia or schizoaffective disorder categorized as being either neuroleptic-responsive or neuroleptic-resistant. Patterns of childhood and adolescent asociality were found to be different in neuroleptic-resistant and neuroleptic-responsive patients. Pre-morbid asociality during the pre-adult years was not consistently worse in patients with poor response to neuroleptic treatment. Greater impairment in late adolescent psychosexual functioning was predictive of poor outcome with regard to neuroleptic treatment.