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1.
Transl Psychiatry ; 11(1): 249, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33907188

RESUMO

The Hamilton Depression Rating Scale (HDRS-17) measures symptoms that may overlap with common antidepressant side effects (e.g., sexual dysfunction), thus making it possible that side effects of antidepressant treatment are erroneously rated as symptoms of depression, and vice versa. This study uses patient-level data from previously conducted antidepressant treatment trials to assess whether side effect ratings co-vary with HDRS-17 ratings. Data from all HDRS-17-rated, industry-sponsored pre- and post-marketing trials (n = 4647) comparing the serotonin and noradrenaline reuptake inhibitor, duloxetine, to placebo and/or to a selective serotonin reuptake inhibitor were pooled; three studies, which utilised sub-therapeutic doses, did not have symptom-level ratings available and could not be included. Severity was assessed for side effects related to sleep, somatic anxiety, gastrointestinal function, and sexual dysfunction. Analysis of covariance was used to assess the relation between these side effects and ratings of relevant HDRS-17-derived outcome parameters. Side effects related to sleep, somatic anxiety and sexual dysfunction significantly and exclusively associated with higher scores on HDRS-17 items measuring the corresponding domains. Side effects related to gastrointestinal function associated with higher HDRS-17 item scores on all assessed domains. Treatment outcome was significantly related to side effect severity when assessed using HDRS-17-sum (beta 0.32 (0.074), p < 0.001), but not when the HDRS-6-sum-score (beta 0.035 (0.043), p = 0.415) or the depressed mood item (beta 0.007 (0.012), p = .527) were used as effect parameters. That some HDRS-17 items co-vary with common antidepressant side effects suggests some of these adverse events are counted twice, potentially leading to an underestimation of antidepressant efficacy.

2.
Acta Neuropsychiatr ; : 1-8, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33593455

RESUMO

OBJECTIVE: Whereas numerous experimental and clinical studies suggest a complex involvement of serotonin in the regulation of anxiety, it remains to be clarified if the dominating impact of this transmitter is best described as anxiety-reducing or anxiety-promoting. The aim of this study was to assess the impact of serotonin depletion on acquisition, consolidation, and expression of conditioned fear. METHODS: Male Sprague-Dawley rats were exposed to foot shocks as unconditioned stimulus and assessed with respect to freezing behaviour when re-subjected to context. Serotonin depletion was achieved by administration of a serotonin synthesis inhibitor, para-chlorophenylalanine (PCPA) (300 mg/kg daily × 3), (i) throughout the period from (and including) acquisition to (and including) expression, (ii) during acquisition but not expression, (iii) after acquisition only, and (iv) during expression only. RESULTS: The time spent freezing was significantly reduced in animals that were serotonin-depleted during the entire period from (and including) acquisition to (and including) expression, as well as in those being serotonin-depleted during either acquisition only or expression only. In contrast, PCPA administrated immediately after acquisition, that is during memory consolidation, did not impact the expression of conditioned fear. CONCLUSION: Intact serotonergic neurotransmission is important for both acquisition and expression of context-conditioned fear.

3.
Acta Psychiatr Scand ; 143(5): 434-443, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33404081

RESUMO

OBJECTIVE: Since several recent meta-analyses report a dose-response relationship for the antidepressant effect of the selective serotonin reuptake inhibitors (SSRIs), we investigated how these drugs are dosed in clinical practice. METHODS: Through linkage of nation- or region-wide registers, we describe SSRI doses in 50,365 individuals residing in Region Västra Götaland, Sweden, with an incident diagnosis of depression and initiating SSRI treatment between 2007 and 2016. The primary question was to elucidate to what extent these individuals had been prescribed a daily dose that according to recent meta-analyses is required to elicit the maximum antidepressant effect, that is >20 mg citalopram, >10 mg escitalopram, >10 mg fluoxetine, >10 mg paroxetine or >50 mg sertraline. RESULTS: In all, 21,049 (54%) out of 38,868 individuals <65 years of age, and 9,131 (79%) out of 11,497 individuals ≥65 years of age, never received an SSRI dose reported to exert maximum antidepressant effect. These prescribing practices were seen for citalopram, escitalopram and sertraline, but not for fluoxetine and paroxetine, and were frequent in both primary and secondary/tertiary care. Suggesting that doses here defined as maximum efficacy doses, when prescribed, are usually not intolerable, between 59% and 68% of individuals <65 years of age received such a dose also for the subsequent prescription, that is as frequently as in those prescribed a sub-maximum efficacy dose (52-69%). CONCLUSION: Most patients being prescribed an SSRI to treat their depression never receive the dose that according to recent meta-analyses is most likely to effectively combat their condition. The lack of consensus regarding effective dosing of SSRIs may have contributed to this state of affairs.

4.
Acta Psychiatr Scand ; 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32940342

RESUMO

In treatment trials, as well as in clinical practice, a number of individuals with depression fail to respond to medications with established antidepressant properties. The presence of such non-responders has been considered as indicative of inter-individual variability in treatment responsiveness, but disparate outcomes between individuals could also be due to other factors, such as inter-individual differences in disease severity and spontaneous improvement (1). To address this issue, recent studies (1,2) have compared variability (specifically standard deviations, SDs) between groups administered active treatment and placebo across trials. When no differences in variability have been found, this has been quoted as an argument against antidepressants being effective or against the value of precision medicine in depression (1).

6.
Acta Neuropsychiatr ; : 1-7, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32063244

RESUMO

OBJECTIVE: Although the assessment of expression of serotonin-related genes in experimental animals has become a common strategy to shed light on variations in brain serotonergic function, it remains largely unknown to what extent the manipulation of serotonin levels causes detectable changes in gene expression. We therefore chose to investigate how sub-acute depletion or elevation of brain serotonin influences the expression of a number of serotonin-related genes in six brain areas. METHODS: Male Wistar rats were administered a serotonin synthesis inhibitor, para-chlorophenylalanine (p-CPA), or a serotonin reuptake inhibitor, paroxetine, for 3 days and then sacrificed. The expression of a number of serotonin-related genes in the raphe nuclei, hypothalamus, amygdala, striatum, hippocampus and prefrontal cortex was investigated using real-time quantitative PCR (rt-qPCR). RESULTS: While most of the studied genes were uninfluenced by paroxetine treatment, we could observe a robust downregulation of tryptophan hydroxylase-2 in the brain region where the serotonergic cell bodies reside, that is, the raphe nuclei. p-CPA induced a significant increase in the expression of Htr1b and Htr2a in amygdala and of Htr2c in the striatum and a marked reduction in the expression of Htr6 in prefrontal cortex; it also enhanced the expression of the brain-derived neurotrophic factor (Bdnf) in raphe and hippocampus. CONCLUSION: With some notable exceptions, the expression of most of the studied genes is left unchanged by short-term modulation of extracellular levels of serotonin.

7.
Acta Neuropsychiatr ; 32(1): 54-56, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31701850

RESUMO

In two previous letters on an selective serotonin reuptake inhibitor (SSRI) meta-analysis conducted by the Copenhagen Trial Unit at Copenhagen University Hospital, we have commented on a large number of errors, almost all of which have tilted the results in an anti-drug direction, that unfortunately mar this publication. While the authors have acknowledged many of these mishaps, and may now be expected to submit an extensive errata list to the journal where their paper was once published, we regretfully note that also their latest contribution to this exchange is surprisingly inaccurate. However, its many shortcomings notwithstanding, their meta-analysis does add to the current literature by confirming that SSRIs do not seem to enhance the risk for suicide or death, and also that these drugs seem to enhance the risk of side effects categorised as serious only in the elderly.


Assuntos
Inibidores de Captação de Serotonina , Suicídio , Dinamarca
8.
J Affect Disord ; 261: 230-237, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31655378

RESUMO

BACKGROUND: Correct prediction of treatment response is a central goal of precision psychiatry. Here, we tested the predictive accuracy of a variety of pre-treatment patient characteristics, including clinical, demographic, molecular genetic, and neuroimaging markers, for treatment response in patients with social anxiety disorder (SAD). METHODS: Forty-seven SAD patients (mean±SD age 33.9 ±â€¯9.4 years, 24 women) were randomized and commenced 9 weeks' Internet-delivered cognitive behavior therapy (CBT) combined either with the selective serotonin reuptake inhibitor (SSRI) escitalopram (20 mg daily [10 mg first week], SSRI+CBT, n = 24) or placebo (placebo+CBT, n = 23). Treatment responders were defined from the Clinical Global Impression-Improvement scale (CGI-I ≤ 2). Before treatment, patients underwent functional magnetic resonance imaging and the Multi-Source Interference Task taxing cognitive interference. Support vector machines (SVMs) were trained to separate responders from nonresponders based on pre-treatment neural reactivity in the dorsal anterior cingulate cortex (dACC), amygdala, and occipital cortex, as well as molecular genetic, demographic, and clinical data. SVM models were tested using leave-one-subject-out cross-validation. RESULTS: The best model separated treatment responders (n = 24) from nonresponders based on pre-treatment dACC reactivity (83% accuracy, P = 0.001). Responders had greater pre-treatment dACC reactivity than nonresponders especially in the SSRI+CBT group. No other variable was associated with clinical response or added predictive accuracy to the dACC SVM model. LIMITATIONS: Small sample size, especially for genetic analyses. No replication or validation samples were available. CONCLUSIONS: The findings demonstrate that treatment outcome predictions based on neural cingulate activity, at the individual level, outperform genetic, demographic, and clinical variables for medication-assisted Internet-delivered CBT, supporting the use of neuroimaging in precision psychiatry.

9.
Neuropsychopharmacology ; 45(3): 553-560, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31521062

RESUMO

Oft-cited trial-level meta-analyses casting doubt on the usefulness of antidepressants have been based on re-analyses of to what extent the active drug has outperformed placebo in reducing the sum score of the Hamilton Depression Rating Scale (HDRS-17-sum) in clinical trials. Recent studies, however, suggest patient-level analyses of individual HDRS items to be more informative when assessing the efficacy of an antidepressant. To shed further light on both symptom-reducing and symptom-aggravating effects of a serotonin and noradrenaline reuptake inhibitor, duloxetine, when used for major depression in adults, we hence applied this approach to re-analyse data from 13 placebo-controlled trials. In addition, using patient-level data from 28 placebo-controlled trials of selective serotonin reuptake inhibitors (SSRIs), the response profile of duloxetine was compared to that of these drugs. Duloxetine induced a robust reduction in depressed mood that was not dependent on baseline severity and not caused by side-effects breaking the blind. A beneficial effect on depressed mood was at hand already after one week; when outcome was assessed using HDRS-17-sum as effect parameter, this early response was however masked by a concomitant deterioration with respect to adverse event-related items. No support for a suicide-provoking effect of duloxetine was obtained. The response profile of duloxetine was strikingly similar to that of the SSRIs. We conclude that the use of HDRS-17-sum as effect parameter underestimates the true efficacy and masks an early effect of duloxetine on core symptoms of depression. No support for major differences between duloxetine and SSRIs in clinical profile were obtained.

10.
Mol Psychiatry ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712720

RESUMO

Panic disorder (PD) has a lifetime prevalence of 2-4% and heritability estimates of 40%. The contributory genetic variants remain largely unknown, with few and inconsistent loci having been reported. The present report describes the largest genome-wide association study (GWAS) of PD to date comprising genome-wide genotype data of 2248 clinically well-characterized PD patients and 7992 ethnically matched controls. The samples originated from four European countries (Denmark, Estonia, Germany, and Sweden). Standard GWAS quality control procedures were conducted on each individual dataset, and imputation was performed using the 1000 Genomes Project reference panel. A meta-analysis was then performed using the Ricopili pipeline. No genome-wide significant locus was identified. Leave-one-out analyses generated highly significant polygenic risk scores (PRS) (explained variance of up to 2.6%). Linkage disequilibrium (LD) score regression analysis of the GWAS data showed that the estimated heritability for PD was 28.0-34.2%. After correction for multiple testing, a significant genetic correlation was found between PD and major depressive disorder, depressive symptoms, and neuroticism. A total of 255 single-nucleotide polymorphisms (SNPs) with p < 1 × 10-4 were followed up in an independent sample of 2408 PD patients and 228,470 controls from Denmark, Iceland and the Netherlands. In the combined analysis, SNP rs144783209 showed the strongest association with PD (pcomb = 3.10 × 10-7). Sign tests revealed a significant enrichment of SNPs with a discovery p-value of <0.0001 in the combined follow up cohort (p = 0.048). The present integrative analysis represents a major step towards the elucidation of the genetic susceptibility to PD.

12.
Eur J Pharmacol ; 864: 172718, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31586629

RESUMO

Whereas the potential role of serotonin for the pathophysiology of irritable bowel syndrome (IBS) has since long been discussed, the possibility that 5-hydroxytryptamine 6 (5-HT6) receptors may serve as targets for the treatment of this condition has as yet not been explored. The aim of the current study was to assess to what extent defecation in rats is influenced by manipulation of 5-HT6 receptors. Reduced defecation following SB-399885 was observed in non-stressed animals assessed for 7 h after drug administration. While not impacting context-conditioned freezing, three 5-HT6 receptor antagonists (SB-399885, SB-271046 and SB-258585) also markedly reduced the number of faecal boli produced by rats exposed to context-conditioned fear. In contrast, a 5-HT6 receptor agonist, WAY-208466, influenced defecation neither in unstressed animals nor in rats experiencing conditioned fear stress. A clinical study on the possible effect of a 5-HT6 receptor antagonist in IBS with diarrhea appears warranted.


Assuntos
Defecação/efeitos dos fármacos , Diarreia/complicações , Diarreia/fisiopatologia , Síndrome do Intestino Irritável/complicações , Receptores de Serotonina/metabolismo , Antagonistas da Serotonina/farmacologia , Animais , Condicionamento Psicológico/efeitos dos fármacos , Diarreia/tratamento farmacológico , Diarreia/psicologia , Medo/efeitos dos fármacos , Medo/psicologia , Masculino , Ratos , Ratos Sprague-Dawley , Antagonistas da Serotonina/uso terapêutico , Estresse Psicológico/psicologia
13.
Lancet Psychiatry ; 6(9): 745-752, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31303567

RESUMO

BACKGROUND: Reports claiming that antidepressants are effective only in patients with severe depression have affected treatment guidelines but these reports usually use a disputed measure of improvement, a decrease in the sum-score of the 17-item Hamilton Depression Rating Scale (HDRS-17), and are based on group-level rather than patient-level data. METHOD: In this item-based, patient-level, post-hoc analysis, we pooled data from all completed, acute-phase, placebo-controlled, industry-sponsored, HDRS-based trials of the SSRIs citalopram, paroxetine, or sertraline in adult major depression. Patient-level data were pooled and subjected to item-based post-hoc analyses to assess the effect of baseline severity of depression on the response to treatment as assessed with HDRS-17 sum score, the depressed mood item of the HDRS, a six-item HDRS subscale (HDRS-6), and the remaining 11 HDRS items not included in this subscale (non-HDRS-6). Patients were defined as having non-severe depression if they had a baseline HDRS-17 sum score of 18 points or less and as having severe depression if they had a score of 27 points or more. FINDINGS: Our study population consisted of 8262 patients from 28 placebo-controlled SSRI trials. Participants were treated with either citalopram (n=744), paroxetine (n=2981), sertraline (n=1202), fluoxetine (active-control group; n=754), or placebo (n=2581). 654 patients were defined as having non-severe depression and 1377 as having severe depression. Patients with non-severe and severe depression did not differ with respect to SSRI-induced decrease in depressed mood and other HDRS symptoms belonging to the HDRS-6 subscale. However, after exclusion of patients with rare extreme baseline values, a positive association was seen between severity and efficacy when using HDRS-17 sum score as the effect parameter. This result was largely due to a more pronounced response to treatment with respect to non-HDRS-6 items in patients with severe depression than in those with non-severe depression. This outcome could be explained by non-HDRS-6 items, more so than HDRS-6 items, being more severe and prevalent at baseline in severe than in non-severe cases; hence, less room was left for improvement in these areas in patients with non-severe depression. INTERPRETATION: The use of an outcome measure that includes symptoms that rate low at baseline in patients with non-severe depression might result in the interpretation that SSRIs are ineffective in these patients. With respect to alleviation of HDRS-6 items, SSRIs appear to be as effective in patients with non-severe depression as in those with severe depression. FUNDING: Swedish Medical Research Council, AFA Insurance, Swedish Brain Foundation, Sahlgrenska University Hospital (Avtal om Läkarutbildning och Forskning), Bertil Hållsten's Foundation, and Söderberg's Foundation.


Assuntos
Depressão/tratamento farmacológico , Transtorno Depressivo Maior/tratamento farmacológico , Inibidores de Captação de Serotonina/uso terapêutico , Antidepressivos/administração & dosagem , Antidepressivos/uso terapêutico , Citalopram/administração & dosagem , Citalopram/uso terapêutico , Ensaios Clínicos como Assunto , Depressão/psicologia , Transtorno Depressivo Maior/psicologia , Fluoxetina/administração & dosagem , Fluoxetina/uso terapêutico , Humanos , Estudos Longitudinais , Avaliação de Resultados em Cuidados de Saúde , Paroxetina/administração & dosagem , Paroxetina/uso terapêutico , Placebos/administração & dosagem , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Reprodutibilidade dos Testes , Inibidores de Captação de Serotonina/administração & dosagem , Sertralina/administração & dosagem , Sertralina/uso terapêutico , Índice de Gravidade de Doença
14.
Acta Neuropsychiatr ; 31(1): 46-51, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30404671

RESUMO

OBJECTIVE: Whereas long-term administration of selective serotonin reuptake inhibitors (SSRIs) is effective for the treatment of anxiety disorders, acute administration of these drugs may exert a paradoxical anxiogenic effect. The aim of the present study was to explore the possible effect of an SSRI in situations of unconditioned or limited conditioned fear. METHODS: Male Sprague Dawley rats were administered a single dose of an SSRI, escitalopram, before acquisition or expression of context conditioned fear, where noise bursts were used as the unconditioned stimulus. Freezing was assessed as a measure of unconditioned fear (=the acute response to noise bursts) or conditioned fear (=the response to the context), respectively. RESULTS: Noise bursts elicited an acute increase in freezing but no robust conditioned response 7 days after exposure. Administration of escitalopram before testing exacerbated the freezing response during presentation of the unconditioned stimulus and also unmasked a conditioned response; in contrast, administration of escitalopram prior to acquisition did not influence the conditioned response. CONCLUSION: The data suggest that freezing in rats exposed to a stimulus inducing relatively mild fear may be enhanced by acute pretreatment with an SSRI regardless of whether the freezing displayed by the animals is an acute unconditioned response to the stimulus in question or a conditioned response to the same stimulus.


Assuntos
Comportamento Animal/efeitos dos fármacos , Citalopram/farmacologia , Condicionamento Clássico/efeitos dos fármacos , Medo/efeitos dos fármacos , Reação de Congelamento Cataléptica/efeitos dos fármacos , Inibidores de Captação de Serotonina/farmacologia , Animais , Citalopram/administração & dosagem , Masculino , Ruído , Ratos , Ratos Sprague-Dawley , Inibidores de Captação de Serotonina/administração & dosagem
15.
Acta Neuropsychiatr ; 30(5): 266-274, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30022741

RESUMO

Funded by the Danish state to provide guidance in health-related matters, the Copenhagen Trial Unit (CTU) at Rigshospitalet may cause considerable societal harm if allowing their analyses to be influenced by bias and prejudice rather than rigor and impartiality. This is why we found it worthwhile to comment on a report from the CTU in which the authors invoked analyses marred by numerous errors and methodological mistakes to claim that selective serotonin reuptake inhibitors (SSRIs) are harmful and ineffective. The CTU group has now produced a response to our comment which is on par with their original contribution in terms of bias, misconceptions and mistakes. Our conclusion is that the reputation of the CTU would be best served by the authors asking for retraction of their SSRI paper.


Assuntos
Inibidores de Captação de Serotonina , Humanos
16.
Br J Psychiatry ; 212(3): 148-154, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29436321

RESUMO

BACKGROUND: Selective serotonin reuptake inhibitors (SSRIs) have been claimed to elicit or aggravate suicidal ideation. Aims To explore the effect of SSRIs on the suicidality item of the Hamilton Rating Scale for Depression (HRSD). METHOD: We undertook a patient-level mega-analysis of adults with depression participating in industry-sponsored studies of sertraline, paroxetine or citalopram, comparing patients on an SSRI (n = 5681) with those on placebo (n = 2581) with respect to HRSD-rated suicidality. Separate analyses were conducted for young adults (age 18-24; n = 537) and adults (age ≥25; n = 7725). RESULTS: Among adults, the reduction in mean rating of suicidality was larger and the risk for aggravation of suicidality lower in patients receiving an SSRI from week 1 and onwards. In young adults, SSRI treatment neither reduced nor increased suicidality ratings relative to placebo at the end-point. CONCLUSIONS: The net effect of SSRIs on suicidality appears beneficial in people above the age of 24 and neutral in those aged 18-24. Declaration of interest F.H. has received speaker's fees from Servier. E.E. has previously been on the advisory boards and/or received speaker's honoraria and/or research grants from Eli Lilly, GlaxoSmithKline, Servier and Lundbeck.


Assuntos
Transtorno Depressivo/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Inibidores de Captação de Serotonina/farmacologia , Ideação Suicida , Adolescente , Adulto , Fatores Etários , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Adulto Jovem
17.
Acta Neuropsychiatr ; 30(5): 244-250, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-28718394

RESUMO

According to a systematic review on the use of selective serotonin reuptake inhibitors (SSRIs) in adult depression that was recently published in BMC Psychiatry, the results of which have been widely disseminated in lay media, these drugs increase the risk for serious adverse events (SAEs) while exerting poor antidepressant efficacy. A cursory analysis, however, suggests the analysis of SAEs conducted by the authors to be marred by both methodological inaccuracies and blatant errors. After having corrected for these apparent mistakes, we conducted a sensitivity analysis in which we also accounted for a possible moderating effect of age; while this suggests SSRIs to be safe drugs in the non-elderly, they do confirm what is already known, that is, that they may enhance the risk for SAEs in the old. Given the loose definition of SAE, including also innocuous phenomena, the possible clinical significance of the latter observation, however, remains unclear until the nature and actual impact of the SAEs in question have been clarified. Moreover, with respect to efficacy, we find the paper in BMC Psychiatry misleading: first, the authors seem unaware of the well-established shortcomings associated with the conventional efficacy parameter on which their analysis is based, second, they have included suboptimal SSRI doses and third, they have missed some pivotal trials. Unless there are explanations for the many peculiarities in this paper that have escaped us, and which may be satisfactorily clarified by the authors, it seems important that the conclusions presented in this paper be publicly rectified.


Assuntos
Transtorno Depressivo Maior , Inibidores de Captação de Serotonina , Adulto , Idoso , Antidepressivos , Depressão , Emoções , Humanos
18.
Behav Neurosci ; 131(5): 421-27, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28805431

RESUMO

Serotonin signaling is vital for reward processing, and hence, also for decision-making. The serotonin transporter gene linked polymorphic region (5-HTTLPR) has been connected to decision making, suggesting that short-allele carriers (s) are more risk averse than long-allele homozygotes (ll). However, previous research has not identified if this occurs because s-carriers (i) are more sensitive to the uncertainty of the outcomes or (ii) are more sensitive to the magnitude of the outcomes. This issue was disentangled using a willingness-to-pay task, where the participants evaluated prospects involving certain gains, uncertain gains, and ambiguous gains. The results clearly favored the hypothesis that s-carriers react more to the magnitude of the outcomes. Self-reported measures of everyday risk-taking behavior also favored this hypothesis. We discuss how these results are in line with recent research on the serotonergic impact on reward processing. (PsycINFO Database Record


Assuntos
Tomada de Decisões/fisiologia , Percepção/fisiologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Adolescente , Adulto , Alelos , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Recompensa , Risco , Assunção de Riscos , Serotonina/farmacologia , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/fisiologia , Incerteza
19.
Behav Brain Res ; 326: 256-264, 2017 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-28284953

RESUMO

Apolipoprotein E (APOE) ε4 has been associated with smaller hippocampal volumes in healthy aging, while findings in young adults are inconclusive. Previous studies have mostly used univariate methods, and without considering potential anterior/posterior differences. Here, we used a multivariate method, partial least squares, and assessed whole-brain structural covariance of the anterior (aHC) and posterior (pHC) hippocampus in young adults (n=97) as a function of APOE ε4 status and sex. Two significant patterns emerged: (1) specific structural covariance of the aHC with frontal regions, temporal and occipital areas in APOE ε4 women, whereas the volume of both the aHC and pHC in all other groups co-varied with frontal, parietal and cerebellar areas; and (2) opposite structural covariance of the pHC in ε4 carriers compared to the aHC in non-carriers, with the pHC of ε4 carriers covarying with parietal and frontal areas, and the aHC of ε4 non-carriers covarying with motor areas and the middle frontal gyrus. APOE ε4 has in young adults been associated with better episodic and spatial memory, functions involving the aHC and pHC, respectively. We found no associations between structural covariance and performance, suggesting that other factors underlie the performance differences seen between carriers and non-carriers. Our findings indicate that APOE ε4 carriers and non-carriers differ in hippocampal organization and that there are differences as a function of sex and hippocampal segment. They stress the need to consider the hippocampus as a heterogeneous structure, and highlight the benefits of multivariate methods in assessing group differences in the brain.


Assuntos
Apolipoproteína E4/genética , Encéfalo/anatomia & histologia , Hipocampo/anatomia & histologia , Memória Episódica , Memória Espacial/fisiologia , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Heterozigoto , Hipocampo/diagnóstico por imagem , Humanos , Masculino , Fatores Sexuais , Adulto Jovem
20.
Brain Behav Immun ; 61: 209-216, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27890662

RESUMO

The complement cascade plays a role in synaptic pruning and synaptic plasticity, which seem to be involved in cognitive functions and psychiatric disorders. Genetic variants in the closely related CSMD1 and CSMD2 genes, which are implicated in complement regulation, are associated with schizophrenia. Since patients with schizophrenia often show cognitive impairments, we tested whether variants in CSMD1 and CSMD2 are also associated with cognitive functions per se. We took a discovery-replication approach, using well-characterized Scandinavian cohorts. A total of 1637 SNPs in CSMD1 and 206 SNPs in CSMD2 were tested for association with cognitive functions in the NCNG sample (Norwegian Cognitive NeuroGenetics; n=670). Replication testing of SNPs with p-value<0.001 (7 in CSMD1 and 3 in CSMD2) was carried out in the TOP sample (Thematically Organized Psychosis; n=1025) and the BETULA sample (Betula Longitudinal Study on aging, memory and dementia; n=1742). Finally, we conducted a meta-analysis of these SNPs using all three samples. The previously identified schizophrenia marker in CSMD1 (SNP rs10503253) was also included. The strongest association was observed between the CSMD1 SNP rs2740931 and performance in immediate episodic memory (p-value=5×10-6, minor allele A, MAF 0.48-0.49, negative direction of effect). This association reached the study-wide significance level (p⩽1.2×10-5). SNP rs10503253 was not significantly associated with cognitive functions in our samples. In conclusion, we studied n=3437 individuals and found evidence that a variant in CSMD1 is associated with cognitive function. Additional studies of larger samples with cognitive phenotypes will be needed to further clarify the role of CSMD1 in cognitive phenotypes in health and disease.


Assuntos
Cognição/fisiologia , Proteínas de Membrana/genética , Adulto , Idoso , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Proteínas Supressoras de Tumor
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