Persistent effects of in utero overnutrition on offspring adiposity: the Exploring Perinatal Outcomes among Children (EPOCH) study

Aims/hypothesis: We previously showed that intrauterine exposure to gestational diabetes mellitus (GDM) increases selected markers of adiposity in pre-pubertal adolescents. In the present study, we examined these associations in adolescence, and explored whether they are strengthened as the participants transition through puberty. Methods: Data from 597 individuals (505 unexposed, 92 exposed) participating in the longitudinal Exploring Perinatal Outcomes among Children (EPOCH) study in Colorado were collected at two research visits when the participants were, on average, 10.4 and 16.7 years old. Adiposity measures included BMI, waist/height ratio, and visceral and subcutaneous adipose tissue (as determined by MRI). Separate general linear mixed models were used to assess the longitudinal relationships between exposure to maternal GDM and each adiposity outcome. We tested whether the effect changed over time by including an interaction term between exposure and age in our models, and whether the associations were explained by postnatal behaviours. Results: Compared with unexposed participants, those exposed to maternal GDM had higher BMI (β = 1.28; 95% CI 0.35, 2.21; p < 0.007), waist/height ratio (β = 0.03; 95% CI 0.01, 0.04; p = 0.0004), visceral adipose tissue (β = 4.81; 95% CI 1.08, 8.54; p = 0.01) and subcutaneous adipose tissue (β = 35.15; 95% CI 12.43, 57.87; p < 0.003). The magnitude of these differences did not change over time and the associations did not appear to be explained by postnatal behaviours. Conclusions/interpretation: Our data provide further evidence that intrauterine exposure to maternal GDM is associated with increased offspring adiposity, an effect that appears early in life and tracks throughout adolescence. Efforts to prevent childhood obesity following intrauterine exposure to maternal GDM should target the prenatal or early life periods

Eating disorders in sport : current status and future directions in the study of the psychological factors

Este trabalho procura atingir dois objetivos. Em primeiro lugar, apresenta-se a situação atual da investigação sobre desordens alimentares no desporto. Neste caso, salientam-se as linhas de investigação dedicadas ao estudo da prevalência destes problemas no desporto e analisam-se as diferenças entre atletas e modalidades desportivas. Dadas as dificuldades destas linhas de investigação na compreensão dos comportamentos alimentares de risco nos atletas, são avançadas outras possibilidades de desenvolvimento da investigação. Assim, e enquanto segundo objetivo deste artigo, salientamos a necessidade dos estudos se dirigirem para a compreensão dos fatores psicológicos associados aos comportamentos alimentares de risco e implicados no desenvolvimento das desordens alimentares. Esta abordagem tem como vantagem adicional ajudar a prevenir estes problemas através da promoção das competências mentais dos atletas no sentido de resistirem melhor aos possíveis efeitos nocivos da prática desportiva, onde se inserem os problemas com a alimentação.This paper focuses on two main goals. In first place, we present the current status on the research about eating disorders in sport contexts. In this case, we point out studies dedicated to the analysis of the incidence of eating disorders in sport and studies that observe the differences between athletes and different sports in the tendency for these problems. Second, we proposed new research directions on this subject, namely the need of analysing the psychological factors that are related with the development of eating disorders on athletes. This research approach has the advantage of helping the prevention of eating disorders on athletes through the promotion of psychological skills that protect athletes from the negative effects of sport practicing, where are included maladaptive eating behaviors.(undefined

Estimates of sensitivity and specificity can be biased when reporting the results of the second test in a screening trial conducted in series

Abstract Background Cancer screening reduces cancer mortality when early detection allows successful treatment of otherwise fatal disease. There are a variety of trial designs used to find the best screening test. In a series screening trial design, the decision to conduct the second test is based on the results of the first test. Thus, the estimates of diagnostic accuracy for the second test are conditional, and may differ from unconditional estimates. The problem is further complicated when some cases are misclassified as non-cases due to incomplete disease status ascertainment. Methods For a series design, we assume that the second screening test is conducted only if the first test had negative results. We derive formulae for the conditional sensitivity and specificity of the second test in the presence of differential verification bias. For comparison, we also derive formulae for the sensitivity and specificity for a single test design, both with and without differential verification bias. Results Both the series design and differential verification bias have strong effects on estimates of sensitivity and specificity. In both the single test and series designs, differential verification bias inflates estimates of sensitivity and specificity. In general, for the series design, the inflation is smaller than that observed for a single test design. The degree of bias depends on disease prevalence, the proportion of misclassified cases, and on the correlation between the test results for cases. As disease prevalence increases, the observed conditional sensitivity is unaffected. However, there is an increasing upward bias in observed conditional specificity. As the proportion of correctly classified cases increases, the upward bias in observed conditional sensitivity and specificity decreases. As the agreement between the two screening tests becomes stronger, the upward bias in observed conditional sensitivity decreases, while the specificity bias increases. Conclusions In a series design, estimates of sensitivity and specificity for the second test are conditional estimates. These estimates must always be described in context of the design of the trial, and the study population, to prevent misleading comparisons. In addition, these estimates may be biased by incomplete disease status ascertainment.</p