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OBJECTIVE: The placebo response in depression studies is the change in symptoms amongst those who receive an inactive treatment. Many well-designed randomized controlled trials (RCTs) of depression have a high proportion of placebo responders, with little understanding as to why. The present study assesses characteristics associated with the placebo response in a nutraceutical trial with a large proportion of placebo responders. METHODS: This is a secondary analysis of a nutraceutical depression RCT which identified no overall treatment benefit relative to placebo (n = 69 in placebo group). We investigated participant characteristics such as socio-demographics, clinical features, and recruitment methods, and their association with the placebo response. Monoaminergic genetic polymorphisms were also assessed. Placebo response was measured based on change in Montgomery-Asberg Depression Rating Scale score. The association of these hypothesis-driven variables of interest and the placebo response was examined using linear mixed effects models. RESULTS: Greater levels of education, particularly pursuing post-high school education, better self-reported general health, marriage/de facto, greater improvement in the first trial week, and more failed antidepressant therapies in the current depressive episode were associated with greater placebo response. An increased placebo response was not found in those recruited via social media nor in those with concomitant antidepressant therapy. Single nucleotide polymorphisms from the tryptophan hydroxylase 1 (TPH1) gene (A779C and A218C) were weakly associated with greater placebo response, although the evidence was attenuated after accounting for multiple comparisons. CONCLUSION: This is, to our knowledge, the first study within nutraceutical research for depression to assess the association between participant characteristics and variation in the placebo response. Several variables appeared to predict the placebo response. Such findings may encourage future trial designs which could dampen placebo response, improve assay sensitivity, and allow for treatment effects to be potentially more detectable. Please cite this article as: Arnold R, Murphy-Smith J, Ng CH, Mischoulon D, Byrne GJ, Bousman CA, Stough C, Berk M, Sarris J. Predictors of the placebo response in a nutraceutical randomized controlled trial for depression. J Integr Med. 2024; 22(1): 46-53.
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Antidepressivos , Depressão , Humanos , Depressão/tratamento farmacológico , Antidepressivos/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Ensaios Clínicos Controlados Aleatórios como AssuntoRESUMO
Generalised Anxiety Disorder (GAD) is a prevalent, chronic mental health disorder. The measurement of regional brain gamma-aminobutyric acid (GABA) offers insight into its role in anxiety and is a potential biomarker for treatment response. Research literature suggests Piper methysticum (Kava) is efficacious as an anxiety treatment, but no study has assessed its effects on central GABA levels. This study investigated dorsal anterior cingulate (dACC) GABA levels in 37 adult participants with GAD. GABA was measured using proton magnetic resonance spectroscopy (1H-MRS) at baseline and following an eight-week administration of Kava (standardised to 120 mg kavalactones twice daily) (n = 20) or placebo (n = 17). This study was part of the Kava for the Treatment of GAD (KGAD; ClinicalTrials.gov: NCT02219880), a 16-week intervention study. Compared with the placebo group, the Kava group had a significant reduction in dACC GABA (p = 0.049) at eight weeks. Baseline anxiety scores on the HAM-A were positively correlated with GABA levels but were not significantly related to treatment. Central GABA reductions following Kava treatment may signal an inhibitory effect, which, if considered efficacious, suggests that GABA levels are modulated by Kava, independent of reported anxiety symptoms. dACC GABA patterns suggest a functional role of higher levels in clinical anxiety but warrants further research for symptom benefit. Findings suggest that dACC GABA levels previously un-examined in GAD could serve as a biomarker for diagnosis and treatment response.
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Ansiolíticos , Kava , Adulto , Humanos , Transtornos de Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/psicologia , Biomarcadores , Giro do Cíngulo/diagnóstico por imagem , Kava/química , Neuroimagem , Fitoterapia , Extratos Vegetais/farmacologiaRESUMO
Kava is a South Pacific plant-based medicine with anxiolytic properties, but little is known about the impact kava has on gene expression or whether gene expression can serve as a marker of kava response. This study aimed to determine whether kava treatment alters the expression of genes with physiological relevance to anxiety pathophysiology and whether the baseline expression of these physiologically relevant genes modifies the efficacy of kava treatment. In this post hoc analysis, we examined the expression of 48 genes relevant to the pathophysiology of anxiety collected from a double-blind randomized controlled trial that assessed the efficacy of kava treatment in generalized anxiety disorder. Peripheral blood gene expression was measured in 71 (34 kava, 37 placebo) adults at baseline and in 40 (19 kava, 21 placebo) after 8 weeks of treatment by reverse transcription polymerase chain reaction (PCR). Results revealed that kava decreased the expression of a subunit of the GABAA -rho receptor gene (GABRR2) and catechol-O-methyltransferase (COMT), a gene related to catecholamine metabolism. Kava efficacy was not found to be modified by baseline (pretreatment) expression of relevant genes. Although these results did not withstand statistical correction for multiple comparisons and require external validation, they support the notion that kava's mechanism of action includes interaction with GABAergic and catecholaminergic systems.
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Ansiolíticos , Kava , Humanos , Adulto , Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/uso terapêutico , Fitoterapia , Transtornos de Ansiedade/tratamento farmacológico , Transtornos de Ansiedade/genética , Ansiolíticos/farmacologia , Ansiolíticos/uso terapêutico , Ansiedade/tratamento farmacológico , Ansiedade/genética , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Expressão GênicaRESUMO
The effects of fish oil (FO) or omega-3 supplementation on cognition has been the subject of several previous clinical trials. However, the effect of different doses taken chronically on cognition in children has not been well studied. In order to address this gap in our knowledge, we conducted a randomized, double-blind, placebo-controlled clinical trial. A total of one hundred and twenty healthy, cognitively normal Thai children aged 6-12 years old consumed daily low dose FO (260 mg Docosahexaenoic acid (DHA)), high dose FO (520 mg DHA), or placebo (Soybean oil) for 12 weeks. Cognitive function was assessed using a computerized cognitive battery, including the Go/NoGo, N-Back, and Digit Span tests as well as concurrent event-related potentials (ERPs), which together measured attention, processing speed, inhibition, and memory at baseline and 12 weeks. We hypothesized that compared to placebo, the two FO groups would show improved cognitive performance and shorter ERP latencies. In total, 42, 39, and 39 participants completed each of the test (FO-A, FO-B) and placebo groups (P) allocations, respectively, and were analyzed (120 in total across the three groups). No significant differences were observed between reaction times (RTs), accuracy, or error rates for all three of the cognitive tests. The ERP measurement and analysis of brain activity during the cognitive tests showed an increase in ERP amplitude. For all cognitive tests, there was a dose-response effect of FO on ERP amplitudes. These findings indicate that fish oil intake leads to a consistent improvement in attention and cognitive processing ability measured by changes in brain activity during working and long-term memory processes. This is the first study to directly quantify such an effect through simultaneous measurement of manual and mental activity during cognitive tasks following chronic FO use in children.
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The current study investigated the efficacy of extract of Bacopa monnieri (BM; CDRI 08®) in reducing levels of inattention and hyperactivity in young children. BM has demonstrated improvements in cognitive outcomes in adults, yet little research is available on its effects in younger populations. A 14-week randomized, double-blind, placebo-controlled clinical trial, with placebo run-in and run-out phases, investigated the effects of BM on behavioural, cognitive, mood, and sleep effects in male children aged 6 to 14 years against placebo. One-hundred and twelve participants were recruited into the trial, with 93 datasets available for analysis. No significant behavioural differences were noted between treatment groups. Cognitive outcomes indicated decreased error-making in children taking CDRI 08® (p = .04) and increased speed of reaction time in those taking placebo (p = .04) at study end. Improvements in cognitive flexibility (p = .01), executive functioning (p = .04), interpersonal problems (p = .02), and sleep routine (p = .04) were noted in those consuming CDRI 08® over placebo. CDRI 08® did not improve behavioural outcomes, but may have cognitive, mood and sleep benefits in children aged 6 to 14 years. Further study is required to support the findings presented here.
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Bacopa , Adolescente , Adulto , Afeto , Criança , Pré-Escolar , Cognição , Método Duplo-Cego , Humanos , Masculino , Extratos Vegetais/uso terapêutico , Resultado do TratamentoRESUMO
PURPOSE: Depression clinical trials are increasingly studying biomarkers to predict and monitor response to treatment. Assessment of biomarkers may reveal subsets of patients who are responsive to nutraceutical treatment, which may facilitate a personalized approach to treating depression. METHODS: This is a post hoc analysis of an 8-week, double-blind, randomized, controlled trial (n = 158) investigating a combination nutraceutical comprising Omega-3 (EPA 1 g/DHA 656 mg), SAMe, zinc, 5-HTP, folinic acid, and co-factors versus placebo for the treatment of Major Depressive Disorder. The study explored levels of polyunsaturated fatty acids, folate, vitamin B12, zinc, homocysteine, and BDNF as possible predictors and correlates of response to nutraceutical supplementation. RESULTS: Concentrations of EPA and DHA in red cell membranes increased in response to treatment and were significantly correlated with a decrease in depressive symptoms during active treatment (p = 0.003 and p = 0.029; respectively). Higher baseline levels of omega-6 fatty acid also correlated with depression reduction in the active treatment group ( p = 0.011). No other biomarkers were associated with a lessening of depressive symptoms. CONCLUSION: Changes in fatty acid levels resulting from a nutraceutical combination containing EPA and DHA provide a response biomarker in treating depression.
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Transtorno Depressivo Maior/dietoterapia , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Adulto , Biomarcadores/análise , Método Duplo-Cego , Membrana Eritrocítica/química , Feminino , Humanos , MasculinoRESUMO
OBJECTIVE: Previous randomised, double-blind, placebo-controlled studies have shown that Kava (a South Pacific medicinal plant) reduced anxiety during short-term administration. The objective of this randomised, double-blind, placebo-controlled study was to perform a larger, longer-term trial assessing the efficacy and safety of Kava in the treatment of generalised anxiety disorder and to determine whether gamma-aminobutyric acid transporter (SLC6A1) single-nucleotide polymorphisms were moderators of response. METHODS: The trial was a phase III, multi-site, two-arm, 16-week, randomised, double-blind, placebo-controlled study investigating an aqueous extract of dried Kava root administered twice per day in tablet form (standardised to 120 mg of kavalactones twice/day) in 171 currently non-medicated anxious participants with diagnosed generalised anxiety disorder. The trial took place in Australia. RESULTS: An analysis of 171 participants revealed a non-significant difference in anxiety reduction between the Kava and placebo groups (a relative reduction favouring placebo of 1.37 points; p = 0.25). At the conclusion of the controlled phase, 17.4% of the Kava group were classified as remitted (Hamilton Anxiety Rating Scale score < 7) compared to 23.8% of the placebo group (p = 0.46). No SLC6A1 polymorphisms were associated with treatment response, while carriers of the rs2601126 T allele preferentially respond to placebo (p = 0.006). Kava was well tolerated aside from poorer memory (Kava = 36 vs placebo = 23; p = 0.044) and tremor/shakiness (Kava = 36 vs placebo = 23; p = 0.024) occurring more frequently in the Kava group. Liver function test abnormalities were significantly more frequent in the Kava group, although no participant met criteria for herb-induced hepatic injury. CONCLUSION: While research has generally supported Kava in non-clinical populations (potentially for more 'situational' anxiety as a short-term anxiolytic), this particular extract was not effective for diagnosed generalised anxiety disorder.
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Ansiolíticos/uso terapêutico , Transtornos de Ansiedade/tratamento farmacológico , Kava/química , Extratos Vegetais/uso terapêutico , Adulto , Ansiolíticos/efeitos adversos , Transtornos de Ansiedade/genética , Austrália , Método Duplo-Cego , Feminino , Proteínas da Membrana Plasmática de Transporte de GABA/genética , Humanos , Masculino , Pessoa de Meia-Idade , Fitoterapia , Extratos Vegetais/efeitos adversos , Raízes de Plantas/química , Polimorfismo de Nucleotídeo Único , Escalas de Graduação Psiquiátrica , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
B vitamins are essential for optimal brain and body function, and are particularly important for cortical metabolic processes that have downstream effects on mitigating oxidative stress. Oxidative stress has been linked to poor psychological outcomes including psychological distress, which has wide-reaching implications for the community and the workplace. Given work-related stress has been associated with poor mental health outcomes, high-dose B vitamin supplementation may be effective in improving brain function and psychological outcomes via attenuation of oxidative stress. This randomized, double-blind, placebo-controlled study investigated psychological outcomes following 6-month supplementation of a high-B-vitamin multivitamin in a large sample of healthy adults (n = 108, aged 30-70 years), as well as changes in default mode network functional connectivity in a subset of the original sample (n = 28). Improvements in occupational stress, general health, perceived stress, depressive symptoms, and mood profiles were identified for both active and placebo groups over time (p < 0.05 corrected). Seed-based functional connectivity analysis centered on the posterior cingulate cortex (PCC) showed that connectivity between the PCC and the caudate increased for the active treatment group, but decreased for the placebo group (p < 0.05 corrected). These findings reveal a substantial intervention effect for both active and placebo treatments, which could in part be associated with a placebo effect in subjective measures. There was, however, a significant treatment effect in the objective measure of functional connectivity, suggesting that reduced psychological stress and high-B-vitamin multivitamin supplementation may lead to an increase in DMN and caudate functional connectivity, which might reflect a strengthening of neurocircuitry within areas associated with reward and emotion at rest. Future studies should consider a placebo run-in methodology to reduce the placebo effect on the subjective measures of stress.
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BACKGROUND: One of the most pressing questions in "Nutritional Psychiatry" is whether using combinations of different nutraceuticals with putative antidepressant activity may provide an enhanced synergistic antidepressant effect. METHODS: A phase II/III, Australian multi-site, 8-week, double-blind, RCT involving 158 outpatients with a DSM-5 diagnosis of MDD. The intervention consisted of a nutraceutical combination: S-adenosyl methionine; Folinic acid; Omega-3 fatty acids; 5-HTP, Zinc picolinate, and relevant co-factors versus placebo. The primary outcome was change in MADRS score. Hypothesis-driven analyses of potential moderators of response involving key SNPs, and BDNF were also conducted. RESULTS: Placebo was superior to the nutraceutical combination in reducing MADRS score (differential reduction -1.75 points), however a mixed linear model revealed a non-significant Group X Time interaction (pâ¯=â¯0.33). Response rates were 40% for the active intervention and 51% for the placebo; remission rates were 34% and 43% for active and placebo groups, respectively. No significant differences were found between groups on any other secondary depression, anxiety, psychosocial, or sleep outcome measures. Key SNPs and BDNF did not significantly moderate response. No significant differences occurred between groups for total adverse effects, aside from more nausea in the active group. LIMITATIONS: Very high placebo response rates suggest a placebo run-in design may have been valuable. INTERPRETATION: The adoption of a nutraceutical 'shotgun' approach to treating MDD was not supported, and appeared to be less effective than adding placebo to treatment as usual.
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Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Suplementos Nutricionais , Adulto , Idoso , Austrália , Fator Neurotrófico Derivado do Encéfalo/análise , Método Duplo-Cego , Ácidos Graxos Ômega-3/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , S-Adenosilmetionina/uso terapêutico , Adulto JovemRESUMO
BACKGROUND: The Australian Research Council Longevity Intervention (ARCLI) was designed to investigate the effects of two active supplements, Pycnogenol and Bacopa monnieri (CDRI08) on cognitive performance in a cohort of elderly participants. An additional antioxidant supplement has been included into the trial. A neuroimaging component has also been added to the ARCLI study to investigate the neurochemical biomarkers of oxidative stress in vivo, as well as structural and functional changes associated with ageing and oxidative stress. Faecal biomarkers of gut microflora will also be analysed to investigate if gut microbiota are associated with domains of cognition (e.g., attention, processing speed, memory), mood or other ARCLI outcome variables. The aim of this paper is to update the published methods of the ARCLI clinical trial before it is completed, and data analysis commences. METHODS: ARCLI is a randomised, placebo controlled, double-blind, now 4-arm clinical trial including neuroimaging and gut microflora sub-studies. Along with the demographic, haematological, mood, cardiovascular and cognitive assessments described in the initial protocol, 80 eligible participants from the overall study pool of ~ 400 will be recruited into the neuroimaging study and undergo scans at baseline, 3 months and 12 months. Proton magnetic resonance spectroscopy, resting state functional connectivity and arterial spin labelled perfusion sequences are neuroimaging techniques included for each MRI visit in the study. Similarly, approximately 300 participants from the main study pool will be recruited to provide faecal samples at baseline, 3 months and 12 months so that the gut microbiome can be studied. DISCUSSION: ARCLI is 12-month intervention study, currently underway with a group of older adults, investigating a range of outcomes and their association with ageing. The additional measurements in the ARCLI trial will further the understanding of the underlying mechanisms associated with healthy ageing and may provide insights into novel preventative therapeutic strategies for maintaining cognitive and brain health into old age. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000487970 .
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Envelhecimento/fisiologia , Cognição/fisiologia , Microbioma Gastrointestinal/fisiologia , Longevidade/fisiologia , Neuroimagem , Afeto , Antioxidantes/administração & dosagem , Austrália , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Sistema Cardiovascular , Protocolos Clínicos , Suplementos Nutricionais , Método Duplo-Cego , Promoção da Saúde , Humanos , Imageamento por Ressonância Magnética , Estresse Oxidativo/fisiologia , PlacebosRESUMO
A diet rich in B-group vitamins is essential for optimal body and brain function, and insufficient amounts of such vitamins have been associated with higher levels of neural inflammation and oxidative stress, as marked by increased blood plasma homocysteine. Neural biomarkers of oxidative stress quantified through proton magnetic spectroscopy (1H-MRS) are not well understood, and the relationship between such neural and blood biomarkers is seldom studied. The current study addresses this gap by investigating the direct effect of 6-month high-dose B-group vitamin supplementation on neural and blood biomarkers of metabolism. Using a randomized, double-blind, placebo-controlled design, 32 healthy adults (20 female, 12 male) aged 30â»65 years underwent blood tests (vitamin B6, vitamin B12, folate, and homocysteine levels) and 1H-MRS of the posterior cingulate cortex (PCC) and dorsolateral prefrontal cortex (DLPFC) before and after supplementation. Results confirmed the supplement was effective in increasing vitamin B6 and vitamin B12 levels and reducing homocysteine, whereas there was no change in folate levels. There were significant relationships between vitamin B6 and N-acetylaspartate (NAA), choline, and creatine, as well as between vitamin B12 and creatine (ps < 0.05), whereas NAA in the PCC increased, albeit not significantly (p > 0.05). Together these data provide preliminary evidence for the efficacy of high-dose B-group supplementation in reducing oxidative stress and inflammation through increasing oxidative metabolism. It may also promote myelination, cellular metabolism, and energy storage.
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Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Complexo Vitamínico B/farmacologia , Adulto , Idoso , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Biomarcadores/metabolismo , Encéfalo/metabolismo , Cognição , Transtornos Cognitivos , Creatina/metabolismo , Método Duplo-Cego , Feminino , Homocisteína/metabolismo , Humanos , Inflamação/prevenção & controle , Masculino , Pessoa de Meia-Idade , Complexo Vitamínico B/sangue , Complexo Vitamínico B/metabolismoRESUMO
There has been increasing interest in nutraceutical augmentation strategies to boost the efficacy of antidepressants. This study assessed whether S-adenosylmethionine (SAMe), a methyl donor that occurs naturally in the body, may be of such benefit. We conducted an 8-week, double-blind RCT in which 107 treatment non-remittent outpatients with DSM-5 diagnosed Major Depressive Disorder (MDD) were randomized to either SAMe or placebo adjunctively to antidepressants. One-carbon cycle nutrients, pertinent single nucleotide polymorphisms (SNPs), and BDNF were also analysed as potential moderators of response. A linear mixed-effects model revealed a significant overall reduction in Montgomery-Asberg Depression Rating Scale (MADRS) score across time, however there was no significant between-group difference observed (pâ¯=â¯0.51). Response rates at Week 8 were 54.3% in the SAMe group and 50.0% in the placebo group, with remission rates 43.5% for SAMe and 38.3% for placebo (all results NS). No effect of SAMe was found on any secondary outcome. Differential response to SAMe was not modified by a range of key genotypes (e.g. COMT), nor reflected in a change of homocysteine, red cell folate, or BDNF. Use of SAMe elicited no significant adverse effects beyond placebo, however it was implicated in one case of serotonin syndrome-like symptoms. This study concludes that 800â¯mg/day of SAMe is not an effective adjunctive treatment in MDD, and no obvious biomarker reflected any differential response to treatment. Due to such a distinctly high placebo-response (despite rigorous screening), future studies should employ a placebo run-in period and other strategies to minimize placebo response.
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Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/terapia , Suplementos Nutricionais , S-Adenosilmetionina/uso terapêutico , Adulto , Terapia Combinada , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , S-Adenosilmetionina/efeitos adversos , Falha de TratamentoRESUMO
Hemp-derivative (Cannabis sativa L.) food products containing trace levels of Δ-9-tetrahydrocannabinol (THC) are proposed for consumption in Australia and New Zealand; however, it is unclear whether use of these products will negatively affect existing drug screening protocols. This double-blind, within-subjects, cross-over trial assessed 35 adults (17 male; 18 female), aged 22-52 years [Mean=30.7, Standard Deviation (S.D)±7.6]. Low dose THC oil [5mL bearer sesame oil containing 10mg/kg THC (0.046mg THC per 5mL dose)]; high dose THC oil [5mL bearer sesame oil containing 20mg/kg THC (0.092mg THC per 5mL dose)]; and a placebo oil (THC negative) was consumed during a three-week protocol. The Securetec Drugwipe® II Twin device assessed THC presence (cut-off 20ng/mL) in oral fluid at baseline, at 5, 30, 60, 120 and 240min post-treatment. Blood was drawn at baseline, 30, 120 and 240min post-treatment, and urine at baseline and 240min post-treatment. No THC was detected in oral fluid, blood or urine samples at any time-point following consumption of the low or high THC dose. Trace concentrations of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCa) were detected in blood 4-h after consumption of the high THC treatment (M=0.0001mg/L) and in urine at 4-h post consumption of both low and high THC treatments (M=0.0001mg/L and 0.0004mg/L, respectively). Consumption of low-content THC oil does not result in positive biological assessments. It is therefore highly unlikely that ingestion of products containing these levels of THC will negatively impact existing region-specific drug driving enforcement protocols.
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Cannabis , Dronabinol/análise , Alimentos , Óleos de Plantas/análise , Saliva/química , Adulto , Estudos Cross-Over , Método Duplo-Cego , Dronabinol/análogos & derivados , Feminino , Humanos , Imunoensaio , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
High anxiety and depression are often observed in the Australian adolescent population, and if left untreated, can have long-term negative consequences impacting educational attainment and a range of important life outcomes. The utilization of mindfulness techniques has been associated with decreased anxiety and depression, but the underlying mechanisms for this is only beginning to be understood. Previous research with adult samples has suggested that the development of emotional intelligence (EI) may be one mechanism by which mindfulness confers its benefits on wellbeing. This study is the first to examine the relation between mindfulness, EI, anxiety, and depression in an adolescent population. It was hypothesized that EI would mediate the relationships between mindfulness and anxiety, as well as mindfulness and depression. The sample consisted of 108 adolescents from a public secondary school, aged between 13 and 15 years (M age = 13.68, SD age = 0.56, 51 males and 57 females). Participants completed an online self-report questionnaire which measured dispositional mindfulness, EI, anxiety, and depression. The results indicated that one subscale of EI - Emotional Recognition and Expression (ERE) mediated the relation between mindfulness and anxiety, while two subscales of EI - ERE and Emotional Management and Control (EMC) mediated the relation between mindfulness and depression. Future research utilizing a mindfulness intervention should be conducted to examine whether the use of mindfulness increases EI and decreases anxiety and depression in adolescents.
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Anxiety disorders are chronic and functionally disabling conditions with high psychological stress, characterised by cognitive symptoms of excessive worry and focus difficulties and physiological symptoms such as muscle tension and insomnia. Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter within the central nervous system and is a key target of pharmacotherapies in the treatment of anxiety. Although current pharmaceutical treatments are often efficacious, they may cause undesirable side effects including cognitive decrements and withdrawal symptoms. Plant-based "phytomedicines" may provide novel treatment options, to act as an adjunctive or alternative to existing anxiolytic medications. As such, we conducted a systematic review to assess the current body of literature on anxiolytic phytomedicines and/or phytoconstituents. An open-ended search to 5 July 2017 was conducted using MEDLINE (PubMed), Scopus, and Cochrane library online databases and performed in a stepped format from preclinical to clinical investigations. Eligible studies must have had (a) in vitro evidence of GABA-modulating activity, (b) animal studies using anxiety models to test an anxiolytic effect, and (c) human clinical trials. Ten phytomedicines were identified as having preclinical investigations showing interaction with the GABA system, in addition to human clinical trials: kava, valerian, pennywort, hops, chamomile, Ginkgo biloba, passionflower, ashwagandha, skullcap, and lemon balm. Collectively, the literature reveals preclinical and clinical evidence for various phytomedicines modulating GABA-pathways, with comparative anxiolytic effect to the current array of pharmaceuticals, along with good safety and tolerability profiles.
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Transtornos de Ansiedade/tratamento farmacológico , Agonistas de Receptores de GABA-A/uso terapêutico , Fitoterapia/métodos , Animais , Agonistas de Receptores de GABA-A/farmacologia , HumanosRESUMO
Several studies have indicated a chronic cognitive enhancing effect of Bacopa monnieri across different ages and cognitive impairment associated with vitamin and mineral deficiencies in children. Therefore, we investigated the effects of 4-month supplementation with a combination of B. monnieri extract and multiple micronutrients on cognitive functions in Indian school children aged 7-12 years. This was a randomized, double-blind, parallel design, single-center study in which 300 children were randomized to receive a beverage either fortified with B. monnieri and multiple micronutrients ("fortified") or a non-fortified isocaloric equivalent ("control") twice-daily for 4 months. Cognitive function was assessed by the Cambridge Neuropsychological Automated Test Battery (CANTAB) administered at baseline, Day 60 and Day 121. The primary endpoint was change in short-term memory (working memory) from baseline in subjects receiving "fortified" vs. "control" beverages after 4 months. Secondary endpoints included sustained attention, episodic memory, and executive function. The "fortified" beverage did not significantly improve short-term memory or any of the secondary outcomes tested relative to the "control" beverage. However, the spatial working memory "strategy" score showed significant improvement on Day 60 (difference between groups in change from baseline: -0.55; p < 0.05), but not on Day 121 due to the active intervention. Study products were well-tolerated. Reasons for these unexpected findings are discussed.
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Background: Chronic psychological stress and mental health disorders are endemic in Western culture where population dietary insufficiencies of omega-3 fatty acids (n-3FA) from seafood have been observed. Objective: This study was designed to test for a causal relationship between one of the most active components of fish oil, eicosapentaenoic acid (EPA), and chronic psychological stress. Method: A randomized double-blind, placebo-controlled clinical trial with parallel-assignment to two groups was designed (Trial Id: ACTRN12610000404022). The interventions were four EPA-rich fish oil capsules per day, delivering 2.2 g/d EPA (and 0.44 g/d DHA), or identical placebo (low-phenolic olive oil capsules with 5% fish oil to aid blinding). The primary outcome was the between-group difference on the Perceived Stress Scale (PSS-10) after 12 weeks supplementation. An a priori power analysis determined that group sizes of 43 would provide 80% power to detect a significant between-group difference of 12.5%, at α = 0.05. Ninety community members (64 females, 26 males) reporting chronic work stress were recruited via public advertising in northern NSW, Australia. Results: At baseline the omega-3 index (EPA + DHA as % to total fatty acids in red blood cell membranes) was 5.2% in both groups (SD = 1.6% control group; 1.8% active group). After supplementation this remained stable at 5.3% (SD = 1.6%) for the control group but increased to 8.9% (SD = 1.5%) for the active group, demonstrating successful incorporation of EPA into cells. Intention-to-treat (ITT) analysis found no significant between-group differences in PSS outcome scores post-intervention (b = 1.21, p = 0.30) after adjusting for sex (b = 2.36, p = 0.079), baseline PSS (b = 0.42, p = 0.001) and baseline logEPA [b = 1.41, p = 0.185; F(3, 86) = 8.47, p < 0.01, n = 89, R-square = 0.243]. Discussion: Treatment increased cell membrane EPA but, contrary to the hypothesis, there was no effect on perceived stress. Limitations included an imbalance of gender in groups after randomization (68% of the males were in the placebo group). While we found no significant interaction between sex and group on the outcome after adjusting for baseline PSS, larger studies with groups stratified for gender may be required to further confirm these findings. Conclusion: This study demonstrated that 2. 2 g/day of EPA for 12 weeks did not reduce chronic psychological stress.
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Background: The Ayurvedic medicinal system employs a holistic approach to health, utilising the synergistic properties of organic resources. Research into the Ayurvedic herb Bacopa monnieri (L.) Wettst. (B.monnieri) has reported improvements in cognitive outcomes in child and adult populations. The aim of current review is to systematically assess and critically summarize clinical trials investigating B.monnieri-dominant poly-herbal formulas and their effects on the cognition, memory, learning, and behaviour in children and adolescents. Methods: Key word searches were performed using PubMed, Scopus, Cochrane Library, DHARA, and CINAHL for publications meeting inclusion criteria up to November 2017. There were no restrictions in study design. Effect sizes were calculated for all significant findings to allow for direct comparisons, and each study was evaluated on design quality. Cognitive and behavioural outcomes were grouped into validated constructs for cross-study comparison. Results: Nine trials met inclusion criteria. Five studies reported sufficient data for effect size analysis with most improvements reported in behavioural outcomes. True cognitive abilities and behavioural constructs were reviewed in six studies, with visual perception, impulsivity, and attention demonstrating the greatest improvements. The veracity of the evidence for the formulations reviewed is weakened by inconsistent statistical design and under-reporting of safety and tolerability data (44%). Conclusions: The current review extends research supporting B.monnieri as a cognitive enhancer and provides modest evidence for the use of B.monnieri in poly-herbal preparations for improving cognitive and behavioural outcomes in child and adolescent populations. Greater emphasis on statistical vigour and the reporting of tolerability data are essential for future trials to adequately document poly-herbal treatment efficacy.
RESUMO
Advances in healthcare have considerably improved the life expectancy of the human population over the last century and this has brought about new challenges. As we live longer the capacity for cognitive aging increases. Consequently, it has been noted that decline in cognitive performance in the elderly in domains of reasoning, problem solving skills, attention, processing speed, working memory and episodic memory is a significant societal problem. Despite the enormity of this issue there are relatively few interventions for cognitive aging. This may be due to our current state of knowledge on biological factors that underpin cognitive aging. One of the biological contributors to cognitive aging is chronic neuroinflammation. This review will provide an overview of the peripheral and central mechanisms involved in chronic neuroinflammation and how neuroinflammation may be related to age-associated cognitive decline. Plant based extracts including herbal and nutritional supplements with anti-inflammatory properties will be examined in relation to their utility in treating age-related cognitive decline. Plant based extracts in particular offer interesting pharmacological properties that may be quickly utilized to prevent cognitive aging.
RESUMO
INTRODUCTION: This study investigated the effects of a marine oil extract (PCSO-524®) on inattention, hyperactivity, mood and cognition in children and adolescents. PCSO-524® is a standardised lipid extract of the New Zealand green-lipped mussel and is an inflammatory modulator that inhibits the 5'-lipoxygenase and cyclooxygenase pathways and decreases concentrations of the pro-inflammatory arachidonic acid (AA). METHODS: PCSO-524® or a matched placebo was administered for 14 weeks to 144 participants (123 males/21 females; mean age 8.7 years) with high hyperactivity and inattention in a randomised, double-blind, placebo-controlled study. The primary outcome was the Conners Parent Rating Scale assessing parental reports of behavioural problems. Secondary outcomes assessed changes in cognition and mood. RESULTS: The results of the present study did not support the hypothesis that PCSO-524® improves parental reports of hyperactivity, inattention and impulsivity in children ages 6 to 14 years over placebo. Repeated measures ANOVA on post hoc subsample analysis indicated significant improvements in hyperactivity (p = 0.04), attention (p = 0.02), learning (p = 0.05) and probability of ADHD (p = 0.04) with a medium to large average effect size (d = 0.65) in those children who did not meet criteria for combined hyperactivity and inattention. Furthermore, significant improvements in the PCSO-524® group were indicated in a whole sample repeated measures ANCOVA on recognition memory between baseline and week 8 over placebo (p = 0.02, d = 0.56); this difference was not sustained at week 14. CONCLUSIONS: The results presented indicate that PCSO-524® may be beneficial in reducing levels of hyperactivity and inattention in a population of children with clinical and subclinical symptoms of ADHD.