Sue Jeavons

N-acetyl cysteine as a glutathione precursor for schizophrenia--a double-blind, randomized, placebo-controlled trial.

BACKGROUND Brain glutathione levels are decreased in schizophrenia, a disorder that often is chronic and refractory to treatment. N-acetyl cysteine (NAC) increases brain glutathione in rodents. This study was conducted to evaluate the safety and effectiveness of oral NAC (1 g orally twice daily [b.i.d.]) as an add-on to maintenance medication for the treatment of chronic schizophrenia over a 24-week period. METHODS A randomized, multicenter, double-blind, placebo-controlled study. The primary readout was change from baseline on the Positive and Negative Symptoms Scale (PANSS) and its components. Secondary readouts included the Clinical Global Impression (CGI) Severity and Improvement scales, as well as general functioning and extrapyramidal rating scales. Changes following a 4-week treatment discontinuation were evaluated. One hundred forty people with chronic schizophrenia on maintenance antipsychotic medication were randomized; 84 completed treatment. RESULTS Intent-to-treat analysis revealed that subjects treated with NAC improved more than placebo-treated subjects over the study period in PANSS total [-5.97 (-10.44, -1.51), p = .009], PANSS negative [mean difference -1.83 (95% confidence interval: -3.33, -.32), p = .018], and PANSS general [-2.79 (-5.38, -.20), p = .035], CGI-Severity (CGI-S) [-.26 (-.44, -.08), p = .004], and CGI-Improvement (CGI-I) [-.22 (-.41, -.03), p = .025] scores. No significant change on the PANSS positive subscale was seen. N-acetyl cysteine treatment also was associated with an improvement in akathisia (p = .022). Effect sizes at end point were consistent with moderate benefits. CONCLUSIONS These data suggest that adjunctive NAC has potential as a safe and moderately effective augmentation strategy for chronic schizophrenia.

N-acetyl cysteine for depressive symptoms in bipolar disorder--a double-blind randomized placebo-controlled trial.

BACKGROUND Treatment-resistant subthreshold depression is a major problem in bipolar disorder. Both depression and bipolar disorder are complicated by glutathione depletion. We hypothesized that treatment with N-acetyl cysteine (NAC), a safe, orally bioavailable precursor of glutathione, may improve the depressive component of bipolar disorder. METHODS A randomized, double-blind, multicenter, placebo-controlled study of individuals (n = 75) with bipolar disorder in the maintenance phase treated with NAC (1 g twice daily) adjunctive to usual medication over 24 weeks, with a 4-week washout. The two primary outcomes were the Montgomery Asberg Depression Rating Scale (MADRS) and time to a mood episode. Secondary outcomes included the Bipolar Depression Rating Scale and 11 other ratings of clinical status, quality of life, and functioning. RESULTS NAC treatment caused a significant improvement on the MADRS (least squares mean difference [95% confidence interval]: -8.05 [-13.16, -2.95], p = .002) and most secondary scales at end point. Benefit was evident by 8 weeks on the Global Assessment of Functioning Scale and Social and Occupational Functioning Assessment Scale and at 20 weeks on the MADRS. Improvements were lost after washout. There was no effect of NAC on time to a mood episode (log-rank test: p = .968) and no significant between-group differences in adverse events. Effect sizes at end point were medium to high for improvements in MADRS and 9 of the 12 secondary readouts. CONCLUSIONS NAC appears a safe and effective augmentation strategy for depressive symptoms in bipolar disorder.

The efficacy of N-acetylcysteine as an adjunctive treatment in bipolar depression: An open label trial

BACKGROUND Evidence is accumulating to support the presence of redox dysregulation in a number of psychiatric disorders, including bipolar disorder. This dysregulation may be amenable to therapeutic intervention. Glutathione is the predominant non-enzymatic intracellular free radical scavenger in the brain, and the most generic of all endogenous antioxidants in terms of action. N-acetylcysteine (NAC) is a glutathione precursor that effectively replenishes brain glutathione. Given the failure of almost all modern trials of antidepressants in bipolar disorder to demonstrate efficacy, and the limited efficacy of mood stabilisers in the depressive phase of the disorder, this is a major unmet need. METHOD This study reports data on the treatment of 149 individuals with moderate depression during the 2 month open label phase of a randomised placebo controlled clinical trial of the efficacy of 1g BID of NAC that examined the use of NAC as a maintenance treatment for bipolar disorder. RESULTS In this trial, the estimated mean baseline Bipolar Depression Rating Scale (BDRS) score was 19.7 (SE=0.8), and the mean BDRS score at the end of the 8 week open label treatment phase was 11.1 (SE=0.8). This reduction was statistically significant (p<0.001). Improvements in functioning and quality of life were similarly evident. CONCLUSION These open label data demonstrate a robust decrement in depression scores with NAC treatment. Large placebo controlled trials of acute bipolar depression are warranted.

The efficacy of adjunctive N-acetylcysteine in major depressive disorder: a double-blind, randomized, placebo-controlled trial.

OBJECTIVE Major depressive disorder (MDD) is one of the most common psychiatric disorders, conferring considerable individual, family, and community burden. To date, treatments for MDD have been derived from the monoamine hypothesis, and there is a paucity of emerging antidepressants, especially with novel mechanisms of action and treatment targets. N-acetylcysteine (NAC) is a redox-active glutathione precursor that decreases inflammatory cytokines, modulates glutamate, promotes neurogenesis, and decreases apoptosis, all of which contribute to the neurobiology of depression. METHOD Participants with a current episode of MDD diagnosed according to DSM-IV-TR criteria (N = 252) were treated with NAC or placebo in addition to treatment as usual for 12 weeks and were followed to 16 weeks. Data were collected between 2007 and 2011. RESULTS The omnibus interaction between group and visit for the Montgomery-Asberg Depression Rating Scale (MADRS), the primary outcome measure, was not significant (F₁,₅₂₀.₉ = 1.98, P = .067), and the groups did not separate at week 12 (t₃₆₀.₃ = -1.12, P = .265). However, at week 12, the scores on the Longitudinal Interval Follow-Up Evaluation-Range of Impaired Functioning Tool (LIFE-RIFT) differed from placebo (P = .03). Among participants with a MADRS score ≥ 25, NAC separated from placebo at weeks 6, 8, 12, and 16 (P < .05). Additionally, the rate of change between baseline and week 16 was significant (t₂₂₁.₀₃ = -2.11, P = .036). NAC treatment was superior to placebo at week 16 for secondary readouts of function and clinical impression. Remission and response were greater in the NAC group at week 16, but not at week 12. The NAC group had a greater rate of gastrointestinal and musculoskeletal adverse events. CONCLUSIONS Being negative at the week 12 end point, and with some positive secondary signals, the study provides only limited support for the role of NAC as a novel adjunctive therapy for MDD. These data implicate the pathways influenced by NAC in depression pathogenesis, principally oxidative and inflammatory stress and glutamate, although definitive confirmation remains necessary. TRIAL REGISTRATION www.anzctr.org.au Identifier: ACTRN12607000134426.

N-acetylcysteine for major depressive episodes in bipolar disorder

OBJECTIVE In this report, we aimed to evaluate the effect of add-on N-acetylcysteine (NAC) on depressive symptoms and functional outcomes in bipolar disorder. To that end, we conducted a secondary analysis of all patients meeting full criteria for a depressive episode in a placebo controlled trial of adjunctive NAC for bipolar disorder. METHOD Twenty-four week randomised clinical trial comparing adjunctive NAC and placebo in individuals with bipolar disorder experiencing major depressive episodes. Symptomatic and functional outcome data were collected over the study period. RESULTS Seventeen participants were available for this report. Very large effect sizes in favor of NAC were found for depressive symptoms and functional outcomes at endpoint. Eight of the ten participants on NAC had a treatment response at endpoint; the same was true for only one of the seven participants allocated to placebo. DISCUSSION These results indicate that adjunctive NAC may be useful for major depressive episodes in bipolar disorder. Further studies designed to confirm this hypothesis are necessary.

N-acetyl cysteine add-on treatment for bipolar II disorder: a subgroup analysis of a randomized placebo-controlled trial

BACKGROUND The evidence base for the pharmacological treatment of bipolar II disorder is limited. In bipolar disorder, there is evidence for glutathione depletion and increased oxidative stress, as well as dysregulation of glutamate; N-acetyl cysteine (NAC) has effects on both of these systems. Add-on NAC has been shown to have a significant benefit on depressive symptoms in a randomized placebo-controlled trial. In this report, we explore the effects of this compound in a subset of patients with bipolar II disorder from that trial. METHODS Individuals were randomized to NAC or placebo in addition to treatment as usual, in a double-blind fashion. Mood and functional outcomes were assessed up to 24 weeks of treatment. RESULTS Fourteen individuals were available for this report, seven in each group. Six people achieved full remission of both depressive and manic symptoms in the NAC group; this was true for only two people in the placebo group (χ(2)=4.67, p=0.031). LIMITATIONS Subgroup analyses in a small subsample of patients. Not all participants had elevated depression scores at baseline. CONCLUSION Notwithstanding all the limitations that subgroup analysis of trials carry, this data could serve as a hypothesis-generating stimulus for further clinical trials of pharmacologic treatment for bipolar II depression.

Predicting who suffers psychological trauma in the first year after a road accident

This study followed up a cohort (n = 72) of consecutive road accident attendees to hospital for one year, assessing them soon after the accident and 3, 6 and 12 months later with the General Health Questionnaire (28-item version); Impact of Event Scale and Posttraumatic Stress Disorder Interview. The aim of the study was to identify demographic, accident and subjective reality variables that could predict who was likely to suffer psychological disorder in the future. The extent of injury was a particular focus for the study. Results showed that at different time periods, using stepwise, multiple regression analyses, between 12 and 77% of variance in trauma measures could be predicted. Severity of injury was a stronger predictor longer after the accident.

Maintenance N-acetyl cysteine treatment for bipolar disorder: A double-blind randomized placebo controlled trial

BackgroundN-acetyl cysteine (NAC) is a glutathione precursor that has been shown to have antidepressant efficacy in a placebo-controlled trial. The current study aimed to investigate the maintenance effects of NAC following eight weeks of open-label treatment for bipolar disorder.MethodThe efficacy of a double blind randomized placebo controlled trial of 2 g/day NAC as adjunct maintenance treatment for bipolar disorder was examined. Participants (n = 149) had a Montgomery Asberg Depression Rating Score of ≥12 at trial entry and, after eight weeks of open-label NAC treatment, were randomized to adjunctive NAC or placebo, in addition to treatment as usual. Participants (primarily outpatients) were recruited through public and private services and through newspaper advertisements. Time to intervention for a mood episode was the primary endpoint of the study, and changes in mood symptoms, functionality and quality of life measures were secondary outcomes.ResultsThere was a substantial decrease in symptoms during the eight-week open-label NAC treatment phase. During the subsequent double-blind phase, there was minimal further change in outcome measures with scores remaining low. Consequently, from this low plateau, between-group differences did not emerge on recurrence, clinical functioning or quality of life measures.ConclusionsThere were no significant between-group differences in recurrence or symptomatic outcomes during the maintenance phase of the trial; however, these findings may be confounded by limitations.Trial RegistrationThe trial was registered with the Australian New Zealand Clinical Trials Registry (ACTRN12607000074493).

Nail-Biting Stuff? The Effect of N-acetyl Cysteine on Nail-Biting

N-acetyl cysteine (NAC) is a widely available nutraceutical with a variety of actions. As a precursor of cysteine and glutathione, it has antioxidant properties that may impact on mood and contribute to an effect on impulsivity and obsessive behaviour. Via its additional effect on glutamate via the cystine-glutamate exchange system, NAC has been shown to mediate impulsivity in preclinical models of addiction, reduce craving, and cue extinction. Further, by boosting glutathione, NAC acts as a potent antioxidant and has been shown in two positive, large-scale randomized placebo-controlled trials to affect negative symptoms in schizophrenia and depression in bipolar disorder. We describe three cases in which its actions specifically on nail-biting and associated anxiety may offer a potential treatment. The spontaneous findings are reported as part of an ongoing treatment trial examining the utility of NAC in bipolar disorder. Its actions, if robustly replicated, also point to potential treatment targets in glutathione or glutamate pathways in the brain.

Accident Cognitions and Subsequent Psychological Trauma

This study used a sample of 72 consecutive attendees to hospital following motor vehicle accidents. It aimed to assess the relationship between demographic variables, details of the accident and cognitions about the accident recorded soon afterward, and degree of psychological trauma 3 and 6 months later. Psychological trauma was assessed using the General Health Questionnaire, Impact of Event Scale, and Posttraumatic Stress Disorder Interview. A structured interview was used to gain information about demographic, accident, and accident cognition variables. Results showed that initial cognitions such as perceived threat to life, rather than demographic or accident variables, had the strongest relationships to subsequent trauma.