A systematic review and secondary data analysis of the interactions between the serotonin transporter 5-HTTLPR polymorphism and environmental and psychological factors in eating disorders

Objectives: to summarize and synthesize the growing gene x environment (GxE) research investigating the promoter region of the serotonin transporter gene (5-HTTLPR) in the eating disorders (ED) field, and overcome the common limitation of low sample size, by undertaking a systematic review followed by a secondary data meta-analysis of studies identified by the review. Method: a systematic review of articles using PsycINFO, PubMed, and EMBASE was undertaken to identify studies investigating the interaction between 5-HTTLPR and an environmental or psychological factor, with an ED-related outcome variable. Seven studies were identified by the systematic review, with complete data sets of five community (n = 1750, 64.5% female) and two clinical (n = 426,100% female) samples combined to perform four secondary-data analyses: 5-I-M1PR x Traumatic Life Events to predict ED status (n = 909), 5-HTTLPR x Sexual and Physical Abuse to predict bulimic symptoms (n = 1097), 5-HTTLPR x Depression to predict bulimic symptoms (n = 1256), and 5-HTTLPRx Impulsiveness to predict disordered eating (n = 1149). Results: under a multiplicative model, the low function (s) allele of 5-HTTLPR interacted with traumatic life events and experiencing both sexual and physical abuse (but not only one) to predict increased likelihood of an ED and bulimic symptoms, respectively. However, under an additive model there was also an interaction between sexual and physical abuse considered independently and 5-HTTLPR, and no interaction with traumatic life events. No other GxE interactions were significant. Conclusion: early promising results should be followed-up with continued cross-institutional collaboration in order to achieve the large sample sizes necessary for genetic research

A systematic review and secondary data analysis of the interactions between the serotonin transporter 5-HTTLPR polymorphism and environmental and psychological factors in eating disorders

Contains fulltext : 160325.pdf (publisher's version ) (Closed access)Objectives: To summarize and synthesize the growing gene x environment (GxE) research investigating the promoter region of the serotonin transporter gene (5-HTTLPR) in the eating disorders (ED) field, and overcome the common limitation of low sample size, by undertaking a systematic review followed by a secondary data meta-analysis of studies identified by the review. Method: A systematic review of articles using PsycINFO, PubMed, and EMBASE was undertaken to identify studies investigating the interaction between 5-HTTLPR and an environmental or psychological factor, with an ED-related outcome variable. Seven studies were identified by the systematic review, with complete data sets of five community (n = 1750, 64.5% female) and two clinical (n = 426, 100% female) samples combined to perform four secondary-data analyses: 5-HTTLPR x Traumatic Life Events to predict ED status (n = 909), 5-HTTLPR x Sexual and Physical Abuse to predict bulimic symptoms (n = 1097), 5-HTTLPR x Depression to predict bulimic symptoms (n = 1256), and 5-HTTLPR x Impulsiveness to predict disordered eating (n = 1149). Results: Under a multiplicative model, the low function (s) allele of 5-HTTLPR interacted with traumatic life events and experiencing both sexual and physical abuse (but not only one) to predict increased likelihood of an ED and bulimic symptoms, respectively. However, under an additive model there was also an interaction between sexual and physical abuse considered independently and 5-HTTLPR, and no interaction with traumatic life events. No other GxE interactions were significant. Conclusion: Early promising results should be followed-up with continued cross-institutional collaboration in order to achieve the large sample sizes necessary for genetic research.11 p

A systematic review and secondary data analysis of the interactions between the serotonin transporter 5-HTTLPR polymorphism and environmental and psychological factors in eating disorders

Objectives: to summarize and synthesize the growing gene x environment (GxE) research investigating the promoter region of the serotonin transporter gene (5-HTTLPR) in the eating disorders (ED) field, and overcome the common limitation of low sample size, by undertaking a systematic review followed by a secondary data meta-analysis of studies identified by the review. Method: a systematic review of articles using PsycINFO, PubMed, and EMBASE was undertaken to identify studies investigating the interaction between 5-HTTLPR and an environmental or psychological factor, with an ED-related outcome variable. Seven studies were identified by the systematic review, with complete data sets of five community (n = 1750, 64.5% female) and two clinical (n = 426,100% female) samples combined to perform four secondary-data analyses: 5-I-M1PR x Traumatic Life Events to predict ED status (n = 909), 5-HTTLPR x Sexual and Physical Abuse to predict bulimic symptoms (n = 1097), 5-HTTLPR x Depression to predict bulimic symptoms (n = 1256), and 5-HTTLPRx Impulsiveness to predict disordered eating (n = 1149). Results: under a multiplicative model, the low function (s) allele of 5-HTTLPR interacted with traumatic life events and experiencing both sexual and physical abuse (but not only one) to predict increased likelihood of an ED and bulimic symptoms, respectively. However, under an additive model there was also an interaction between sexual and physical abuse considered independently and 5-HTTLPR, and no interaction with traumatic life events. No other GxE interactions were significant. Conclusion: early promising results should be followed-up with continued cross-institutional collaboration in order to achieve the large sample sizes necessary for genetic research

A systematic review and secondary data analysis of the interactions between the serotonin transporter 5-HTTLPR polymorphism and environmental and psychological factors in eating disorders

Objectives: to summarize and synthesize the growing gene x environment (GxE) research investigating the promoter region of the serotonin transporter gene (5-HTTLPR) in the eating disorders (ED) field, and overcome the common limitation of low sample size, by undertaking a systematic review followed by a secondary data meta-analysis of studies identified by the review. Method: a systematic review of articles using PsycINFO, PubMed, and EMBASE was undertaken to identify studies investigating the interaction between 5-HTTLPR and an environmental or psychological factor, with an ED-related outcome variable. Seven studies were identified by the systematic review, with complete data sets of five community (n = 1750, 64.5% female) and two clinical (n = 426,100% female) samples combined to perform four secondary-data analyses: 5-I-M1PR x Traumatic Life Events to predict ED status (n = 909), 5-HTTLPR x Sexual and Physical Abuse to predict bulimic symptoms (n = 1097), 5-HTTLPR x Depression to predict bulimic symptoms (n = 1256), and 5-HTTLPRx Impulsiveness to predict disordered eating (n = 1149). Results: under a multiplicative model, the low function (s) allele of 5-HTTLPR interacted with traumatic life events and experiencing both sexual and physical abuse (but not only one) to predict increased likelihood of an ED and bulimic symptoms, respectively. However, under an additive model there was also an interaction between sexual and physical abuse considered independently and 5-HTTLPR, and no interaction with traumatic life events. No other GxE interactions were significant. Conclusion: early promising results should be followed-up with continued cross-institutional collaboration in order to achieve the large sample sizes necessary for genetic research

O exercício físico no tratamento da depressão em idosos: revisão sistemática Physical exercise in the treatment of depression in the elderly: a systematic review

OBJETIVOS: Revisar a literatura quanto (I) ao possível efeito protetor do exercício físico sobre a incidência de depressão e (II) à eficácia do exercício físico como intervenção no tratamento da depressão. MÉTODO: Revisão sistemática de artigos em inglês e português nas bases ISI, PubMed, SciELO e LILACS de janeiro de 1993 a maio de 2006, utilizando conjuntamente os termos "depressão", "idosos" e "exercício". Artigos que avaliaram o efeito do exercício em idosos com doenças clínicas ou que utilizaram escalas para depressão somente para um diagnóstico inicial foram excluídos. RESULTADOS: Do total de 155 artigos, 22 atenderam aos critérios de inclusão, e oito foram acrescentados com busca manual. Os artigos de corte transversal (n = 8) utilizaram somente questionários de auto-avaliação para medir os níveis de atividade física. Os artigos longitudinais (n = 22) utilizaram também pedômetro digital, consumo direto de oxigênio e o exercício físico como intervenção metodológica. Os estudos que atenderam ao objetivo I apontaram para uma relação inversamente proporcional entre atividade física e alterações nos níveis de depressão. Os trabalhos que utilizaram o exercício como intervenção terapêutica na depressão encontraram resultados divergentes e apontaram para a interferência de fatores fisiológicos e psicológicos nessa relação. CONCLUSÃO: O papel do exercício e da atividade física no tratamento da depressão direciona-se para duas vertentes: a depressão promove redução da prática de atividades físicas; a atividade física pode ser um coadjuvante na prevenção e no tratamento da depressão no idoso.<br>OBJECTIVES: To review the literature on the (I) possible protective effect of physical activity on the incidence of depression, and (II) on the efficacy of physical exercise as a therapeutic intervention in depression. METHODS: Systematic review of ISI, PubMed, LILACS and SciELO articles in English and Portuguese from January 1993 to May 2005 using the keywords "depression," "elderly," and "exercise." Articles assessing the effect of physical exercise in the elderly with clinical diseases or that used depression scales only for initial diagnosis were excluded. RESULTS: We found 155 articles, 22 of which met the inclusion criteria. Other eight studies were included after a manual search. Cross-sectional studies (n = 8) used only self-evaluation questionnaires to measure the levels of physical activity. Longitudinal studies (n = 22) also used digital pedometer, direct measurements of oxygen consumption and physical exercise as methodological intervention. The studies meeting the first objective pointed to an inverse relationship between physical activity and changes in levels of depression. The studies that used physical activity as a therapeutic intervention in depression found divergent results and pointed to the interference of physiological and psychological factors on this relation. CONCLUSION: There are two aspects involved in the role of physical activity and exercise in the treatment of depression. Depression decreases the practice of physical activities; physical activity may be useful in the treatment and prevention of depression in the elderly

Depression Symptom Severity and Cardiorespiratory Fitness in Healthy and Depressed Adults: A Systematic Review and Meta-Analysis

Background: Depression symptom severity and cardiorespiratory fitness (CRF) are significant predictors of mortality and disability. However, the relationship between the two is unclear. Objective: This meta-analysis assessed the relationship between depression symptom severity and CRF in healthy and depressed adults (aged 18 years and over). Search Methods: The PubMed, Cochrane Library, Google Scholar and ProQuest databases were browsed for relevant English-language studies published from January 2000 to August 2014. Selection Criteria: Studies reporting a correlation between a depression scale and maximum oxygen consumption (VO2peak), as well as studies from the data of which such a correlation could be calculated, were included in this analysis. Data Analysis: Correlation coefficients (CCs) were converted to Fisher’s z values, and the analysis was performed using a random-effects model. Then, summary effects and 95 % confidence intervals (CIs) were converted back to CCs. Results: Sixteen studies (totalling 4039 participants) were included in this analysis. A modest correlation between depression symptom severity and CRF was found (CC −0.16, 95 % CI −0.21 to −0.10), appearing stronger in male participants (CC − 0.22, 95 % CI −0.26 to −0.18) than in female participants (CC −0.12, 95 % CI −0.19 to −0.05; p = 0.01). There was no difference in the summary effect between healthy and depressed adults (p = 0.43). Heterogeneity was moderate (I2 = 33 %; p = 0.09). Conclusions: Depression symptom severity is inversely correlated with CRF, and this correlation is stronger in men than in women. Clinical and prognostic implications of the correlation are discussed. These findings should stimulate further research on the effects of treating one variable on the other

Does physical activity reduce risk for Alzheimer’s disease through interaction with the stress neuroendocrine system?

Lack of physical activity (PA) is a risk factor for Alzheimer's disease (AD) and PA interventions are believed to provide an effective non-pharmacological approach for attenuating the symptoms of this disease. However, the mechanism of action of these positive effects is currently unknown. It is possible that the benefits may be at least partially mediated by effects on the neuroendocrine stress system. Chronic stress can lead to dysfunction of the hypothalamic pituitary adrenal (HPA) axis, leading to aberrant basal and circadian patterns of cortisol secretion and a cascade of negative downstream events. These factors have been linked not only to reduced cognitive function in the non-demented but also increased levels of Amyloid β plaques and protein Tau "tangles" (the neuropathological hallmarks of AD) in mouse models of this disease. However, there is evidence that PA can have restorative effects on the stress neuroendocrine system and related risk factors relevant to AD. We explore the possibility that PA can positively impact upon AD by restoring normative HPA axis function, with consequent downstream effects upon underlying neuropathology and associated cognitive function. We conclude with suggestions for future research to test this hypothesis in patients with AD