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INTRODUCTION: Clinical and laboratory studies demonstrate that placebo and nocebo effects influence various symptoms and conditions after the administration of both inert and active treatments. OBJECTIVE: There is an increasing need for up-to-date recommendations on how to inform patients about placebo and nocebo effects in clinical practice and train clinicians how to disclose this information. METHODS: Based on previous clinical recommendations concerning placebo and nocebo effects, a 3-step, invitation-only Delphi study was conducted among an interdisciplinary group of internationally recognized experts. The study consisted of open- and closed-ended survey questions followed by a final expert meeting. The surveys were subdivided into 3 parts: (1) informing patients about placebo effects, (2) informing patients about nocebo effects, and (3) training clinicians how to communicate this information to the patients. RESULTS: There was consensus that communicating general information about placebo and nocebo effects to patients (e.g., explaining their role in treatment) could be beneficial, but that such information needs to be adjusted to match the specific clinical context (e.g., condition and treatment). Experts also agreed that training clinicians to communicate about placebo and nocebo effects should be a regular and integrated part of medical education that makes use of multiple formats, including face-to-face and online modalities. CONCLUSIONS: The current 3-step Delphi study provides consensus-based recommendations and practical considerations for disclosures about placebo and nocebo effects in clinical practice. Future research is needed on how to optimally tailor information to specific clinical conditions and patients' needs, and on developing standardized disclosure training modules for clinicians.
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Efeito Nocebo , Efeito Placebo , Consenso , Humanos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To assess the evidence for the safety and efficacy of invasive procedures for reducing chronic pain and improving function and health-related quality of life compared with sham (placebo) procedures. DESIGN: Systematic review with meta-analysis. METHODS: Studies were identified by searching multiple electronic databases, examining reference lists, and communicating with experts. Randomized controlled trials comparing invasive procedures with identical but otherwise sham procedures for chronic pain conditions were selected. Three authors independently extracted and described study characteristics and assessed Cochrane risk of bias. Two subsets of data on back and knee pain, respectively, were pooled using random-effects meta-analysis. Overall quality of the literature was assessed through Grading of Recommendations, Assessment, Development, and Evaluation. RESULTS: Twenty-five trials (2,000 participants) were included in the review assessing the effect of invasive procedures over sham. Conditions included low back (N = 7 trials), arthritis (4), angina (4), abdominal pain (3), endometriosis (3), biliary colic (2), and migraine (2). Thirteen trials (52%) reported an adequate concealment of allocation. Fourteen studies (56%) reported on adverse events. Of these, the risk of any adverse event was significantly higher for invasive procedures (12%) than sham procedures (4%; risk difference = 0.05, 95% confidence interval [CI] = 0.01 to 0.09, P = 0.01, I2 = 65%). In the two meta-analysis subsets, the standardized mean difference for reduction of low back pain in seven studies (N = 445) was 0.18 (95% CI = -0.14 to 0.51, P = 0.26, I2 = 62%), and for knee pain in three studies (N = 496) it was 0.04 (95% CI = -0.11 to 0.19, P = 0.63, I2 = 36%). The relative contribution of within-group improvement in sham treatments accounted for 87% of the effect compared with active treatment across all conditions. CONCLUSIONS: There is little evidence for the specific efficacy beyond sham for invasive procedures in chronic pain. A moderate amount of evidence does not support the use of invasive procedures as compared with sham procedures for patients with chronic back or knee pain. Given their high cost and safety concerns, more rigorous studies are required before invasive procedures are routinely used for patients with chronic pain.
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Dor Crônica/terapia , Manejo da Dor/métodos , HumanosRESUMO
OBJECTIVE: Approximately 55-76% of Service members use dietary supplements for various reasons, including pain and related outcomes. This work evaluates current research on dietary ingredients for chronic musculoskeletal pain to inform decisions for practice and self-care, specifically for Special Operations Forces personnel. METHODS: A steering committee convened to develop research questions and factors required for decision-making. Key databases were searched through August 2016. Eligible systematic reviews and randomized controlled trials were assessed for methodological quality. Meta-analysis was applied where feasible. GRADE was used to determine confidence in the effect estimates. The committee made evidence-informed judgments and recommendations for practice and self-care use. RESULTS: Nineteen eligible dietary ingredients were assessed for quality, efficacy, and safety. Avocado soybean unsaponifiables, capsaicin, curcuma, ginger (as a food source), glucosamine, melatonin, polyunsaturated fatty acids, and vitamin D were conditionally recommended as their benefits outweighed risks, but there was still some uncertainty about the trade-offs. No recommendations were made for boswellia, ginger (as a dietary supplement), rose hip, or s-adenosyl-L-methionine. Recommendations were made against the use of collagen, creatine, devil's claw, l-carnitine, methylsulfonylmethane, pycnogenol, willow bark extract, and vitamin E. Research priorities were developed to address gaps precluding stronger recommendations. CONCLUSIONS: Currently the scientific evidence is insufficiently robust to establish definitive clinical practice guidelines, but processes could be established to track the impact of these ingredients. Until then, providers have the evidence needed to make informed decisions about the safe use of these dietary ingredients, and future research can address existing gaps.
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Suplementos Nutricionais , Medicina Baseada em Evidências/métodos , Medicina Militar/métodos , Militares , Dor Musculoesquelética/dietoterapia , Guias de Prática Clínica como Assunto , Medicina Baseada em Evidências/normas , Humanos , Medicina Militar/normas , Dor Musculoesquelética/diagnóstico , Dor Musculoesquelética/epidemiologia , Fitoterapia/métodos , Fitoterapia/normas , Guias de Prática Clínica como Assunto/normas , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/normasRESUMO
BACKGROUND: Placebo and nocebo effects occur in clinical or laboratory medical contexts after administration of an inert treatment or as part of active treatments and are due to psychobiological mechanisms such as expectancies of the patient. Placebo and nocebo studies have evolved from predominantly methodological research into a far-reaching interdisciplinary field that is unravelling the neurobiological, behavioural and clinical underpinnings of these phenomena in a broad variety of medical conditions. As a consequence, there is an increasing demand from health professionals to develop expert recommendations about evidence-based and ethical use of placebo and nocebo effects for clinical practice. METHODS: A survey and interdisciplinary expert meeting by invitation was organized as part of the 1st Society for Interdisciplinary Placebo Studies (SIPS) conference in 2017. Twenty-nine internationally recognized placebo researchers participated. RESULTS: There was consensus that maximizing placebo effects and minimizing nocebo effects should lead to better treatment outcomes with fewer side effects. Experts particularly agreed on the importance of informing patients about placebo and nocebo effects and training health professionals in patient-clinician communication to maximize placebo and minimize nocebo effects. CONCLUSIONS: The current paper forms a first step towards developing evidence-based and ethical recommendations about the implications of placebo and nocebo research for medical practice, based on the current state of evidence and the consensus of experts. Future research might focus on how to implement these recommendations, including how to optimize conditions for educating patients about placebo and nocebo effects and providing training for the implementation in clinical practice.
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Consenso , Prática Clínica Baseada em Evidências , Efeito Nocebo , Efeito Placebo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Relações Médico-PacienteRESUMO
PURPOSE: We performed a systematic review of the currently available evidence on whether psychological treatments are effective for treating depressed primary care patients in comparison with usual care or placebo, taking the type of therapy and its delivery mode into account. METHODS: Randomized controlled trials comparing a psychological treatment with a usual care or a placebo control in adult, depressed, primary care patients were identified by searches in MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and PsycINFO up to December 2013. At least 2 reviewers extracted information from included studies and assessed the risk of bias. Random effects meta-analyses were performed using posttreatment depression scores as outcome. RESULTS: A total of 30 studies with 5,159 patients met the inclusion criteria. Compared with control, the effect (standardized mean difference) at completion of treatment was -0.30 (95% CI, -0.48 to -0.13) for face-to-face cognitive behavioral therapy (CBT), -0.14 (-0.40 to 0.12) for face-to-face problem-solving therapy, -0.24 (-0.47 to -0.02) for face-to-face interpersonal psychotherapy, -0.28 (-0.44 to -0.12) for other face-to-face psychological interventions, -0.43 (-0.62 to -0.24) for remote therapist-led CBT, -0.56 (-1.57 to 0.45) for remote therapist-led problem-solving therapy, -0.40 (-0.69 to -0.11) for guided self-help CBT, and -0.27 (-0.44 to -0.10) for no or minimal contact CBT. CONCLUSIONS: There is evidence that psychological treatments are effective in depressed primary care patients. For CBT approaches, substantial evidence suggests that interventions that are less resource intensive might have effects similar to more intense treatments.
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Transtorno Depressivo/terapia , Atenção Primária à Saúde/métodos , Psicoterapia/métodos , Terapia Cognitivo-Comportamental/métodos , Humanos , Telemedicina/métodos , Resultado do TratamentoRESUMO
PURPOSE: The purpose of this study was to investigate whether antidepressants are more effective than placebo in the primary care setting, and whether there are differences between substance classes regarding efficacy and acceptability. METHODS: We conducted literature searches in MEDLINE, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and PsycINFO up to December 2013. Randomized trials in depressed adults treated by primary care physicians were included in the review. We performed both conventional pairwise meta-analysis and network meta-analysis combining direct and indirect evidence. Main outcome measures were response and study discontinuation due to adverse effects. RESULTS: A total of 66 studies with 15,161 patients met the inclusion criteria. In network meta-analysis, tricyclic and tetracyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), a serotonin-noradrenaline reuptake inhibitor (SNRI; venlafaxine), a low-dose serotonin antagonist and reuptake inhibitor (SARI; trazodone) and hypericum extracts were found to be significantly superior to placebo, with estimated odds ratios between 1.69 and 2.03. There were no statistically significant differences between these drug classes. Reversible inhibitors of monoaminoxidase A (rMAO-As) and hypericum extracts were associated with significantly fewer dropouts because of adverse effects compared with TCAs, SSRIs, the SNRI, a noradrenaline reuptake inhibitor (NRI), and noradrenergic and specific serotonergic antidepressant agents (NaSSAs). CONCLUSIONS: Compared with other drugs, TCAs and SSRIs have the most solid evidence base for being effective in the primary care setting, but the effect size compared with placebo is relatively small. Further agents (hypericum, rMAO-As, SNRI, NRI, NaSSAs, SARI) showed some positive results, but limitations of the currently available evidence makes a clear recommendation on their place in clinical practice difficult.
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Antidepressivos/uso terapêutico , Transtorno Depressivo/tratamento farmacológico , Aceitação pelo Paciente de Cuidados de Saúde , Atenção Primária à Saúde/métodos , Humanos , Resultado do TratamentoRESUMO
OBJECTIVE: We studied the expectation effects associated with brands by labeling placebo interventions (original and generic analgesic) and investigating the potential differences in efficacy between the two placebos in dealing with noxious heat pain, as well as exploring the neurometabolic correlates of the placebo response. DESIGN: We applied a two by two design with two identical placebo interventions that differed only in their labeling. One group was told that they received 500 mg of "Aspirin" (original brand) while the other group was told that they received a popular ASA generic (1A Pharma). After establishing the individual pain level of each subject, we measured pain intensities behaviorally before and after the intervention and looked for corresponding brain areas with increased hemodynamic response using functional magnetic resonance imaging. RESULTS: At the behavioral level, we found decreases in pain intensity from baseline to the intervention condition with the original brand only. At the neuronal level, we specifically observed activations of the anterior insulae under the baseline conditions, complemented by activations of the dorsomedial prefrontal cortex after the interventions. A direct comparison of the two placebo conditions revealed higher values of activation for the bilateral dorsolateral (as well as dorsomedial) prefrontal cortex for the original brand. CONCLUSION: Our data indicate a behavioral placebo response for the original brand only. Expectations by subjects appear to be triggered not only by the placebo treatment itself but also by the trusted brand, which thus serves as an enhanced placebo. Both processes appear to be based on fronto-cortical neural networks, as these areas showed significantly stronger activations with the original brand.
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Antecipação Psicológica , Aspirina/administração & dosagem , Córtex Cerebral/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Dor/tratamento farmacológico , Dor/fisiopatologia , Adulto , Analgésicos/administração & dosagem , Mapeamento Encefálico/métodos , Medicamentos Genéricos/administração & dosagem , Temperatura Alta , Humanos , Masculino , Dor/psicologia , Medição da Dor/efeitos dos fármacos , Projetos Piloto , Efeito Placebo , Estatística como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: A variety of psychological interventions to treat depressive disorders have been developed and are used in primary care. In a systematic review, we compared the effectiveness of psychological treatments grouped by theoretical background, intensity of contact with the health care professional, and delivery mode for depressed patients in this setting. METHODS: Randomized trials comparing a psychological treatment with usual care, placebo, another psychological treatment, pharmacotherapy, or a combination treatment in adult depressed primary care patients were identified by database searches up to December 2013. We performed both conventional pairwise meta-analysis and network meta-analysis combining direct and indirect evidence. Outcome measures were response to treatment (primary outcome), remission of symptoms, post-treatment depression scores and study discontinuation. RESULTS: A total of 37 studies with 7,024 patients met the inclusion criteria. Among the psychological treatments investigated in at least 150 patients face-to-face cognitive behavioral therapy (CBT; OR 1.80; 95 % credible interval 1.35-2.39), face-to-face counselling and psychoeducation (1.65; 1.27-2.13), remote therapist lead CBT (1.87; 1.38-2.53), guided self-help CBT (1.68; 1.22-2.30) and no/minimal contact CBT (1.53; 1.07-2.17) were superior to usual care or placebo, but not face-to-face problem-solving therapy and face-to-face interpersonal therapy. There were no statistical differences between psychological treatments apart from face-to-face interpersonal psychotherapy being inferior to remote therapist-lead CBT (0.60; 0.37-0.95). Remote therapist-led (0.86; 0.21-3.67), guided self-help (0.93; 0.62-1.41) and no/minimal contact CBT (0.85; 0.54-1.36) had similar effects as face-to-face CBT. CONCLUSIONS: The limited available evidence precludes a sufficiently reliable assessment of the comparative effectiveness of psychological treatments in depressed primary care patients. Findings suggest that psychological interventions with a cognitive behavioral approach are promising, and primarily indirect evidence indicates that it applies also when they are delivered with a reduced number of therapist contacts or remotely. SYSTEMATIC REVIEW REGISTRATION: 01KG1012 at http://www.gesundheitsforschung-bmbf.de/de/2852.php.
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Transtorno Depressivo/terapia , Atenção Primária à Saúde/métodos , Psicoterapia/métodos , Antidepressivos/uso terapêutico , Terapia Combinada , Humanos , Modelos Estatísticos , Resultado do TratamentoRESUMO
The autonomic nervous system (ANS) is of paramount importance for daily life. Its regulatory action on respiratory, cardiovascular, digestive, endocrine, and many other systems is controlled by a number of structures in the CNS. While the majority of these nuclei and cortices have been identified in animal models, neuroimaging studies have recently begun to shed light on central autonomic processing in humans. In this study, we used activation likelihood estimation to conduct a meta-analysis of human neuroimaging experiments evaluating central autonomic processing to localize (1) cortical and subcortical areas involved in autonomic processing, (2) potential subsystems for the sympathetic and parasympathetic divisions of the ANS, and (3) potential subsystems for specific ANS responses to different stimuli/tasks. Across all tasks, we identified a set of consistently activated brain regions, comprising left amygdala, right anterior and left posterior insula and midcingulate cortices that form the core of the central autonomic network. While sympathetic-associated regions predominate in executive- and salience-processing networks, parasympathetic regions predominate in the default mode network. Hence, central processing of autonomic function does not simply involve a monolithic network of brain regions, instead showing elements of task and division specificity.
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Sistema Nervoso Autônomo/fisiologia , Encéfalo/fisiologia , Animais , Mapeamento Encefálico , Sistema Nervoso Central/fisiologia , Análise por Conglomerados , Humanos , Funções Verossimilhança , Imageamento por Ressonância Magnética , Magnetoencefalografia , Rede Nervosa/fisiologia , Sistema Nervoso Parassimpático/fisiologia , Tomografia por Emissão de Pósitrons , Sistema Nervoso Simpático/fisiologia , Tomografia Computadorizada de Emissão de Fóton ÚnicoRESUMO
It is widely acknowledged that placebo responses are accompanied by physiological changes in the central nervous system, but little is known about placebo responses on end organ functions. The present chapter aims to fill this gap by reviewing the literature on peripheral placebo responses. Overall, there is a wide range of placebo and nocebo responses on various organ functions of the cardiovascular, the gastrointestinal system, and the respiratory system. Most of these studies used expectation paradigms to elicit placebo and nocebo responses. Expectations can affect heart rate, blood pressure, coronary diameter, gastric motility, bowel motility, and lung function. Classical conditioning can induce placebo respiratory depression after prior exposure to opioid drugs, and habitual coffee drinkers show physiological arousal in response to coffee-associated stimuli. Similar to findings in placebo pain research, peripheral placebo responses can be target specific. The autonomic nervous system is a likely candidate to mediate peripheral placebo responses. Further studies are necessary to identify the brain mechanisms and pathways involved in peripheral placebo responses.
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Pressão Sanguínea , Motilidade Gastrointestinal , Frequência Cardíaca , Efeito Placebo , Respiração , Sistema Nervoso Autônomo/fisiologia , Condicionamento Psicológico , Vasos Coronários/fisiologia , HumanosRESUMO
Spionidae (Polychaeta) collected from seamounts in the Atlantic Ocean were studied. Altogether six species were found of which two are new to science and one belongs to a new genus. Aonidella cf. dayi Maciolek in López-Jamar, 1989 and Glandulospio orestes gen. et sp. nov. were the most common species and occurred on both the Great and Little Meteor Seamount, the Irving Seamount and the Hyeres Seamount. Laonice norgensis Sikorski, 2003 and Malacoceros jirkovi Sikorski, 1992 have a wider distribution in the North Atlantic, including the Mediterranean Sea in case of L. norgensis. Aonides selvagensis Brito, Núñez and Riera, 2006 is only known from the Macaronesian Region. Dipolydora paracaulleryi sp. nov. has been collected from both the Great and Little Meteor Seamounts. All species are compared with morphological similar species and their taxonomy is discussed. Detailed descriptions are provided for the species new to science and descriptions of the previously known species are amended. Accompanying histological studies revealed the presence of very strong dorsoventral musculature in A. cf. dayi and for G. orestes gen. et sp. nov. the presence of glandular organs in the middle body region. Laonice maciolekae Aguirrezabalaga & Ceberio, 2005 was found to be a junior synonym of L. appellöfi Söderström, 1920 and is formally synonymised. Molecular data suggest gene flow between seamounts and autochthonous as well as allochthonous larval recruitment for different species. The results of previous studies by other authors, that polychaete communities of the North Atlantic Seamounts are characterized by low diversity, low rates of endemism, and the predominance of widely distributed (and cosmopolitan) species is not corroborated by our results.
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Poliquetos/classificação , Distribuição Animal , Estruturas Animais/anatomia & histologia , Animais , Oceano Atlântico , Biodiversidade , DNA Mitocondrial/genética , Ecossistema , Dados de Sequência Molecular , Filogenia , Poliquetos/anatomia & histologia , Poliquetos/genéticaRESUMO
PURPOSE: In light of the mounting prevalence of stress in contemporary society and the growing interest in stress reduction methods, this review investigates the potential of taiji as a viable strategy for alleviating stress. METHODS: MEDLINE, EMBASE, the Cochrane Controlled Trials Register (CENTRAL), PsycINFO, and Web of Science were searched up to April 2023 to identify randomized controlled trials of taiji. Studies in both patients and healthy populations were considered. They had to provide a measure of perceived stress and include a no treatment or placebo control group. Data were extracted by two reviewers. Pooled standardized mean differences (SMD) were calculated for perceived stress, biological stress markers, anxiety, depression, and quality of life (QoL). Meta-regression analyses were performed to identify sources of heterogeneity. RESULTS: Eleven trials with a total of 1323 patients comparing taiji to no intervention met the inclusion criteria. The included studies varied strongly with regard to patient characteristics, taiji intervention, and methodological quality. The overall SMD for perceived stress was significant at -0.41 (95% confidence interval, CI, -0.63 to -0.19; I2 = 63%). Exclusion of studies with less than 100 participants yielded a diminished SMD at -0.26 (95% CI, -0.45 to -0.06). The SMD for perceived stress at follow-up was significant (-0.25, 95% CI -0.46 to -0.05). Secondary outcomes highlighted improvements in anxiety and physical QoL, while depression, mental QoL, and biological stress markers remained unchanged. CONCLUSIONS: Results underscore taiji's potential in mitigating perceived stress in both patients and healthy populations, paralleled by enhancements in depressive symptoms, anxiety levels, and physical QoL.
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Estresse Psicológico , Tai Chi Chuan , Humanos , Estresse Psicológico/terapia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Depressão/terapia , AnsiedadeRESUMO
In this work, the diversity of the genus Orbiniella in the Nordic Seas and the North Atlantic waters south of Iceland is studied based on the analyses of molecular markers (mitochondrial COI, 16S rDNA and nuclear ITS2) and morphological characters. Our results showed the presence of at least five genetic lineages in the studied material which could also be morphologically identified by their segmental annulation patterns, the number and the shape of acicular spines, and the length and the shape of pygidial lobes. The species name Orbiniellapetersenae is assigned to one of the lineages restricting its geographical and vertical distribution to the deep-sea areas north of Iceland and Jan Mayen, and three lineages are described as new species (i.e., Orbiniellagriegi Meca & Budaeva, sp. nov., Orbiniellamayhemi Meca & Budaeva, sp. nov., and Orbiniellaparapari Meca & Budaeva, sp. nov.) elevating the number of known species in the genus to 25. Three deep-sea species of Orbiniella in our study are reported only north of the Greenland-Iceland-Scotland Ridge, one deep-sea species found south of the ridge. A single shallow-water species is distributed along the ridge and on the Norwegian shelf.
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INTRODUCTION: For women who have experienced failed attempts at in vitro fertilization (IVF) and face medical issues, leading to infertility, the renewed effort to seek fertility treatment, coupled with decreasing likelihood of success, can exert substantial emotional and physical strains. Consequently, many couples opt to discontinue treatment before attaining pregnancy. The objective of this study was to evaluate the reproductive outcomes in patients with unsuccessful prior IVF attempts who received a complementary treatment designed to alleviate emotional distress and burden. PATIENTS AND METHODS: A retrospective analysis of data from infertile patients who initiated the complementary intervention at a private clinic between January 2014 and December 2016 was conducted. Information on diagnosis, history of infertility, prior assisted reproductive technology treatments, mode of conception, and pregnancy outcomes were retrieved. RESULTS: The data of 133 patients with a history of one or more unsuccessful IVF treatments were analyzed. Patients had an average age of 36.7 years (±4.4 SD) and had been experiencing infertility for an average of 4.6 years (±2.7 SD). The two main causes of their infertility were endometriosis (36.1%, 48 patients) and diminished egg quality (31.6%, 42 patients). By May 2020, a significant proportion of the patients, 81.2% (108 patients), had achieved pregnancy, leading to 94 live births, which represents a 70.7% success rate. These pregnancies mostly resulted from natural cycle IVF (35.1%), donor cycles (23.4%), and conventional IVF (21.3%). The dropout rate was comparatively low at 23.3%. The median time from the start of complementary treatment to delivery was 18 months, with a range of 12-28 months. CONCLUSIONS: This study highlights the potential value of complementary treatment approaches in conjunction with standard medical care for women who have experienced unsuccessful IVF treatments in the past and thus face a reduced chance of motherhood. The reported 71% live birth rate is notably high, indicating that the inclusion of complementary treatments may provide women with past IVF failures a tangible opportunity for achieving successful pregnancy and childbirth. However, these findings need to be confirmed through randomized controlled studies.
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Fertilização in vitro , Resultado da Gravidez , Humanos , Feminino , Adulto , Estudos Retrospectivos , Gravidez , Esperança , Infertilidade Feminina/terapia , Terapias ComplementaresRESUMO
Suggestions about hunger can generate placebo effects on hunger experiences. But, the underlying neurocognitive mechanisms are unknown. Here, we show in 255 women that hunger expectancies, induced by suggestion-based placebo interventions, determine hunger sensations and economic food choices. Functional magnetic resonance imaging in a subgroup (n = 57/255) provides evidence that the strength of expecting the placebo to decrease hunger moderates medial prefrontal cortex activation at the time of food choice and attenuates ventromedial prefrontal cortex (vmPFC) responses to food value. Dorsolateral prefrontal cortex activation linked to interference resolution formally mediates the suggestion-based placebo effects on hunger. A drift-diffusion model characterizes this effect by showing that the hunger suggestions bias participants' food choices and how much they weigh tastiness against the healthiness of food, which further moderates vmPFC-dlPFC psychophysiological interactions when participants expect decreased hunger. Thus, suggestion-induced beliefs about hunger shape hunger addressing economic choices through cognitive regulation of value computation within the prefrontal cortex.
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Encéfalo , Efeito Placebo , Humanos , Feminino , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/fisiologia , Mapeamento Encefálico/métodos , Preferências Alimentares/fisiologia , Imageamento por Ressonância Magnética/métodosRESUMO
INTRODUCTION: Studies on mind-body approaches in patients with advanced pancreatic ductal adenocarcinoma (PDAC) are rare. We performed a pilot study with follow-up until 1 year to explore changes in pain, quality of life (QoL), stress, and negative emotions in patients with advanced PDAC, who regularly practiced a standardized form of spiritual meditation in addition to standard medical care. METHODS: At baseline and every 2 months for a maximum of 1 year, global pain, QoL (global, SEIQoL, FACT-G), spiritual well-being (FACIT-Sp), perceived stress (PSQ-20), anxiety and depression (HADS), and diurnal cortisol secretion (cortisol slope) were assessed. Changes from baseline were explored by pairwise comparisons of available cases. RESULTS: Twenty participants (11 women, 62 ± 9.9 SD years) participated in the study, of whom 9 patients survived the study year. Pairwise comparisons revealed transient improvements of pain after 4 and 6 months (both p values < 0.05), of global QoL after 4, 6, 8, 10 months (all p values < 0.05), of SeiQoL scores after 4 months (p < 0.05), of FACT-G scores after 6 months (p < 0.05), and of FACIT-Sp scores after 2 and 6 months (both p values < 0.05). Furthermore, overall stress levels (PSQ-20) decreased from baseline to 2, 6, and 8 months (all p values < 0.05), and anxiety declined from baseline to 6 months (p < 0.05). Depression scores and the cortisol slope did not change. CONCLUSION: This pilot study demonstrated the acceptability and feasibility of studies on spiritual meditation in patients with advanced PDAC. Randomized controlled trials are warranted to study the effects of spiritual meditation and other mind-body interventions on pain, QoL, and emotional well-being in this patient population.
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Adenocarcinoma , Meditação , Neoplasias Pancreáticas , Humanos , Feminino , Qualidade de Vida/psicologia , Projetos Piloto , Hidrocortisona , Emoções , Neoplasias Pancreáticas/terapia , Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias PancreáticasRESUMO
Nausea often occurs in stressful situations, such as chemotherapy or surgery. Clinically relevant placebo effects in nausea have been demonstrated, but it remains unclear whether stress has an impact on these effects. The aim of this experimental study was to investigate the interplay between acute stress and placebo effects in nausea. 80 healthy female volunteers susceptible to motion sickness were randomly assigned to either the Maastricht Acute Stress Test or a non-stress control condition, and to either placebo treatment or no treatment. Nausea was induced by a virtual vection drum and behavioral, psychophysiological as well as humoral parameters were repeatedly assessed. Manipulation checks confirmed increased cortisol levels and negative emotions in the stressed groups. In the non-stressed groups, the placebo intervention improved nausea, symptoms of motion sickness, and gastric myoelectrical activity (normo-to-tachy (NTT) ratio). In the stressed groups, the beneficial effects of the placebo intervention on nausea and motion sickness remained unchanged, whereas no improvement of the gastric NTT ratio was observed. Results suggest that placebo effects on symptoms of nausea and motion sickness are resistant to experimentally-induced stress. Stress most likely interfered with the validity of the gastric NTT ratio to measure nausea and thus the gastric placebo effect.
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Enjoo devido ao Movimento , Efeito Placebo , Feminino , Humanos , Enjoo devido ao Movimento/tratamento farmacológico , Náusea/etiologia , EstômagoRESUMO
There is accumulating evidence from different methodological approaches that the placebo effect is a neurobiological phenomenon. Behavioral, psychophysiological, and neuroimaging results have largely contributed to accepting the placebo response as real. A major aspect of recent and future advances in placebo research is to demonstrate linkages between behavior, brain, and bodily responses. This article provides an overview of the processes involved in the formation of placebo responses by combining research findings from behavioral, psychophysiological, and neuroimaging methods. The integration of these different methodological approaches is a key objective, motivating our scientific pursuits toward a placebo research that can inform and guide important future scientific knowledge.
Assuntos
Encéfalo/fisiologia , Efeito Placebo , Psicofisiologia , Sistema Nervoso Autônomo/efeitos dos fármacos , Sistema Nervoso Autônomo/fisiologia , Encéfalo/efeitos dos fármacos , Ensaios Clínicos como Assunto/métodos , Ensaios Clínicos como Assunto/tendências , Humanos , Doenças do Sistema Nervoso/psicologia , Doenças do Sistema Nervoso/terapia , Neuroimagem , Placebos/farmacologia , Placebos/uso terapêuticoRESUMO
AIM: To collect data on the use of placebo interventions by GPs in Germany. METHODS: A questionnaire was mailed to 400 randomly selected GPs in Bavaria. Non-responders were reminded by telephone after 4 weeks and were given a second copy of the questionnaire after a further 3 weeks. RESULTS: In all, 208 completed questionnaires were returned. The majority of GPs (88%) have used a placebo at least once in their practice; 45% have used pure placebos, such as saline injections and sugar pills, at least once last year; the median frequency of use was 5 [interquartile range (IQR), 2-10]. The use of impure placebos during the past year was more common: 76% of GPs have used impure placebos, i.e. medical interventions that have pharmacological or physical activity but have no intrinsic effect (e.g. pharmacological or physical action) on the patient's disease or its symptoms, with a median frequency of 20 times per year (IQR, 10-50). The main reason for the use of placebo was a possible psychological effect, followed by the expectation of patients to receive a treatment. For the majority of GPs placebo interventions were ethically justified if they were used for a possible psychological effect. CONCLUSIONS: Placebo interventions are a widely accepted part of medical treatment in German general practices and are used primarily for their psychological effects. Impure placebos are used much more frequently than pure placebos.