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Showing papers by "Chee H. Ng published in 2013"


Journal ArticleDOI
TL;DR: Standardized kava may be a moderately effective short-term option for the treatment of generalized anxiety disorder (GAD), and specific GABA transporter polymorphisms appear to potentially modify anxiolytic response to kava.
Abstract: Kava (Piper methysticum) is a plant-based medicine, which has been previously shown to reduce anxiety. To date, however, no placebo-controlled trial assessing kava in the treatment of generalized anxiety disorder (GAD) has been completed. A total of 75 participants with GAD and no comorbid mood disorder were enrolled in a 6-week double-blind trial of an aqueous extract of kava (120/240 mg of kavalactones per day depending on response) versus placebo. γ-Aminobutyric acid (GABA) and noradrenaline transporter polymorphisms were also analyzed as potential pharmacogenetic markers of response. Reduction in anxiety was measured using the Hamilton Anxiety Rating Scale (HAMA) as the primary outcome. Intention-to-treat analysis was performed on 58 participants who met inclusion criteria after an initial 1 week placebo run-in phase. Results revealed a significant reduction in anxiety for the kava group compared with the placebo group with a moderate effect size (P = 0.046, Cohen d = 0.62). Among participants with moderate to severe Diagnostic and Statistical Manual of Mental Disorders-diagnosed GAD, this effect was larger (P = 0.02; d = 0.82). At conclusion of the controlled phase, 26% of the kava group were classified as remitted (HAMA ≤ 7) compared with 6% of the placebo group (P = 0.04). Within the kava group, GABA transporter polymorphisms rs2601126 (P = 0.021) and rs2697153 (P = 0.046) were associated with HAMA reduction. Kava was well tolerated, and aside from more headaches reported in the kava group (P = 0.05), no other significant differences between groups occurred for any other adverse effects, nor for liver function tests. Standardized kava may be a moderately effective short-term option for the treatment of GAD. Furthermore, specific GABA transporter polymorphisms appear to potentially modify anxiolytic response to kava.

97 citations


Journal ArticleDOI
TL;DR: There was a highly significant correlation between ASEX reduction (improved sexual function and performance) and anxiety reduction in the whole sample and kava significantly increased female's sexual drive compared to placebo, with no negative effects seen in males.
Abstract: Presently, little is known about a number issues concerning kava (Piper methysticum), including (i) whether kava has any withdrawal or addictive effects; (ii) if genetic polymorphisms of the cytochrome (CYP) P450 2D6 liver enzyme moderates any potential adverse effects; and (iii) if medicinal application of kava has any negative or beneficial effect on sexual function and experience. The study design was a 6-week, double-blind, randomized controlled trial (n = 75) involving chronic administration of kava (one tablet of kava twice per day; 120 mg of kavalactones per day, titrated in non-response to two tablets of kava twice per day; 240 mg of kavalactones) or placebo for participants with generalized anxiety disorder. Results showed no significant differences across groups for liver function tests, nor were there any significant adverse reactions that could be attributed to kava. No differences in withdrawal or addiction were found between groups. Interesting, kava significantly increased female's sexual drive compared to placebo (p = 0.040) on a sub-domain of the Arizona Sexual Experience Scale (ASEX), with no negative effects seen in males. Further, it was found that there was a highly significant correlation between ASEX reduction (improved sexual function and performance) and anxiety reduction in the whole sample.

80 citations


Journal ArticleDOI
TL;DR: The objective of this study is to investigate the influence of the 5‐HTTLPR (serotonin transporter‐linked promoter region), cy tochrome P450 2C19, and cytochrome 2D6 polymorphisms on escitalopram and venlafaxine responses in major depressive disorder.
Abstract: Objective The objective of this study is to investigate the influence of the 5-HTTLPR (serotonin transporter-linked promoter region), cytochrome P450 2C19, and cytochrome P450 2D6 polymorphisms on escitalopram (ESC) and venlafaxine (VEN) responses in major depressive disorder. Method A prospective multi-site study of 106 patients (Caucasian and Han Chinese ethnicities) with major depressive disorder treated with either ESC or VEN was conducted. The 17-item Hamilton Depression scale (HDRS), Clinical Global Impression Scale, and an adverse events scale (UKU) were assessed over 8 weeks, blind to genotype. Results At the 8-week end point, a significant HDRS reduction for both ESC and VEN occurred (p < 0.0001). The 5-HTTLPR l/l genotype was associated with significantly greater score reductions on the HDRS compared with s/s carriers (p = 0.016) among Caucasian subjects receiving ESC (n = 47). Response rates were significantly higher for l/l (92%) compared with l/s (61%) and s/s (46%) variants (p = 0.042). For every l allele a participant carried, there was a 3.33 (95% confidence interval 1.25, 8.84; p = 0.02) times greater odds of ESC response. No significant associations between any of the genotypes and adverse effects were found. Conclusion Ethnicity may have differential effects on the 5-HTTLPR genotype-efficacy relationship. Results suggest that l/l allele for 5-HTTLPR is associated with a robust treatment response to ESC in Caucasian subjects only. Copyright © 2013 John Wiley & Sons, Ltd.

34 citations


Journal ArticleDOI
TL;DR: A set of 10 key principles was developed that can be applied in building partnerships for community mental health care consistent with the local cultures, communities and systems in the region and can be useful to minimize fragmentation of community resources.
Abstract: Objectives:Stage Two of the Asia-Pacific Community Mental Health Development Project was established to document successful partnership models in community mental health care in the region. This pa...

17 citations


Journal ArticleDOI
TL;DR: Predicting differential antidepressant efficacy remains an elusive goal in major depressive disorder (MDD), and possible preferential utility of a selective serotonin and noradrenaline reuptake inhibitor in cases of MDD presenting with greater psychomotor retardation is suggested.
Abstract: Predicting differential antidepressant efficacy remains an elusive goal in major depressive disorder (MDD). The aims of this study were three-fold. Firstly, to examine if psychomotor retardation symptoms (item 8 on the 17-item Hamilton Depression Rating Scale) improve preferentially to venlafaxine (VEN) over escitalopram (ESC) treatment. Secondly, whether the 18 item CORE psychomotor signs scale predicted antidepressant remission. Finally, to investigate the role of two norepinephrine transporter gene (NET) polymorphisms (rs2242446 and rs5569) on antidepressant efficacy. Adults with Diagnostic and Statistical Manual of Mental Disorders, 4th ed. MDD (n=113) were treated with ESC or VEN prospectively for 8 weeks and rated serially with the Hamilton Depression Rating Scale. In a subsample (n=51) of patients from one of the three recruitment sites, the CORE psychomotor signs scale was also administered at baseline. Participants treated with VEN had significantly greater reduction in psychomotor retardation symptoms than those treated with ESC. The CORE scale did not predict antidepressant response or remission. Neither NET polymorphism moderated antidepressant efficacy. Findings suggest possible preferential utility of a selective serotonin and noradrenaline reuptake inhibitor in cases of MDD presenting with greater psychomotor retardation. The moderate to small sample size makes a type II error risk possible, and the negative findings need to be interpreted with caution. The positive finding of preferential efficacy of VEN for psychomotor retardation symptoms has potential translational utility.

14 citations


Journal ArticleDOI
TL;DR: If these findings are replicated in larger samples, child abuse history could become an important element of assessing risk benefit balance when initiating antidepressants and may help guide the level of patient review needed during antidepressant initiation.
Abstract: BACKGROUND: Concerns have emerged that initiation of an antidepressant can lead to or exacerbate suicidality. If those more at risk could be identified prior to treatment, treatment risk benefit analysis and patient risk management could be assisted. Aims: This study investigated the role of child abuse and ongoing emotional impact from abuse on the risk of suicidality during the first week of treatment with an antidepressant. The patient sample for this study was drawn from one site of a larger pharmacogenetic study. The hypothesis was that subjects with high impact child abuse would have greater elevation of suicidality during the first week of antidepressant treatment. METHODS: Fifty-one subjects were initiated on either venlafaxine (VEN) or escitalopram (ESC) for major depressive disorder (MDD) and had pre-treatment suicidality assayed with the reasons for living scale (RFLS), which was repeated after one week of treatment. Several clinical, demographic and genotype variables were controlled for. The 15-item Impact of Event Scale (IES-15) was administered to subjects reporting abuse to dichotomise the abuse group into low and high (IES-15 ≥ 26) impact groups for sub-analysis as per the scales validated rating guidelines. RESULTS: Subjects reporting no child abuse exposure were less likely to have increased suicidality during the first week of antidepressant treatment (7.6%) compared to subjects with low impact abuse (38.5%, p = 0.041) and high impact abuse (58.3%, p = 0.009). Only high impact abuse predicted increased suicidality after adjustment for potential confounders such as depression severity (OR = 31.5, 95% CI = 1.3 to 748.7, p = 0.03). CONCLUSIONS: If these findings are replicated in larger samples, child abuse history could become an important element of assessing risk benefit balance when initiating antidepressants and may help guide the level of patient review needed during antidepressant initiation. Language: en

13 citations


Journal ArticleDOI
TL;DR: Aripiprazole was shown to be a modestly effective augmentation therapy for depressive symptoms in bipolar I and II in this small open-label study.
Abstract: This study aims to evaluate the effectiveness of aripiprazole augmentation of maintenance treatment for bipolar disorder in patients with minor or subsyndromal mood episodes while on a stable dose of a mood stabiliser and/or antidepressant. All subjects had a diagnosis of bipolar I or II disorder (Diagnostic and Statistical Manual of Mental Disorders-4th Edition, Text Revision). Open-label aripiprazole was given over 8 weeks initially. The starting dose was 5 to 15 mg/day with a mean final dose of 11.5 mg (±4.6). Patients were assessed at weeks 0, 2, 4 and 8 with the Montgomery-Asberg Depression Rating Scale (MADRS), Young Mania Rating Scale (YMRS) and Clinical Global Impression of Severity (CGI-S). Seventeen of 20 (85%) patients completed week 4, while 14 (70%) patients completed 8 weeks. For intention-to-treat data, there was a significant decrease in MADRS scores over the course of treatment, with a reduction of 6.40 points at endpoint (p < 0.0005). Improvement from baseline was significant at week 2 and remained through to week 8. Similarly, CGI-S scores significantly decreased over the course of study, but not YMRS scores. Aripiprazole was shown to be a modestly effective augmentation therapy for depressive symptoms in bipolar I and II in this small open-label study.

2 citations