Association between reported exposure to road traffic and respiratory symptoms in children: evidence of bias

BACKGROUND: Many studies showing effects of traffic-related air pollution on health rely on self-reported exposure, which may be inaccurate. We estimated the association between self-reported exposure to road traffic and respiratory symptoms in preschool children, and investigated whether the effect could have been caused by reporting bias. METHODS: In a random sample of 8700 preschool children in Leicestershire, UK, exposure to road traffic and respiratory symptoms were assessed by a postal questionnaire (response rate 80%). The association between traffic exposure and respiratory outcomes was assessed using unconditional logistic regression and conditional regression models (matching by postcode). RESULTS: Prevalence odds ratios (95% confidence intervals) for self-reported road traffic exposure, comparing the categories 'moderate' and 'dense', respectively, with 'little or no' were for current wheezing: 1.26 (1.13-1.42) and 1.30 (1.09-1.55); chronic rhinitis: 1.18 (1.05-1.31) and 1.31 (1.11-1.56); night cough: 1.17 (1.04-1.32) and 1.36 (1.14-1.62); and bronchodilator use: 1.20 (1.04-1.38) and 1.18 (0.95-1.46). Matched analysis only comparing symptomatic and asymptomatic children living at the same postcode (thus exposed to similar road traffic) showed similar ORs, suggesting that parents of children with respiratory symptoms reported more road traffic than parents of asymptomatic children. CONCLUSIONS: Our study suggests that reporting bias could explain some or even all the association between reported exposure to road traffic and disease. Over-reporting of exposure by only 10% of parents of symptomatic children would be sufficient to produce the effect sizes shown in this study. Future research should be based only on objective measurements of traffic exposure.

Association between cannabis use and sexual risk behavior among young heterosexual adults

To study the association between cannabis use and frequent sexual risk behavior, we tested the hypothesis of a situational influence of cannabis use in sexual encounters using a combination of global association study and event-level analysis and examined possible mediator variables, including the personality trait of hedonism/risk preference, psychosocial stress, and HIV-related beliefs, using mediation models. The results of a computer-assisted telephone interview of a random sample of 2790 heterosexual men and women aged 16-24 years showed that risky sexual behavior was more frequent in cannabis-using men and women than in non-using persons. The results did not support a situational effect of cannabis intoxication on sexual risk behavior. The more frequent sexual risk behavior among cannabis users was mediated by decreased intentions to use HIV protection, by lower HIV-self-efficacy, and higher risk preference/hedonism. Only among women psychosocial stress was a partial mediator. The findings show that HIV prevention programs for cannabis-using young adults should emphasize the role of person variables instead of situation variables.

Stem cell-related "self-renewal" signature and high epidermal growth factor receptor expression associated with resistance to concomitant chemoradiotherapy in glioblastoma

PURPOSE: Glioblastomas are notorious for resistance to therapy, which has been attributed to DNA-repair proficiency, a multitude of deregulated molecular pathways, and, more recently, to the particular biologic behavior of tumor stem-like cells. Here, we aimed to identify molecular profiles specific for treatment resistance to the current standard of care of concomitant chemoradiotherapy with the alkylating agent temozolomide. PATIENTS AND METHODS: Gene expression profiles of 80 glioblastomas were interrogated for associations with resistance to therapy. Patients were treated within clinical trials testing the addition of concomitant and adjuvant temozolomide to radiotherapy. RESULTS: An expression signature dominated by HOX genes, which comprises Prominin-1 (CD133), emerged as a predictor for poor survival in patients treated with concomitant chemoradiotherapy (n = 42; hazard ratio = 2.69; 95% CI, 1.38 to 5.26; P = .004). This association could be validated in an independent data set. Provocatively, the HOX cluster was reminiscent of a "self-renewal" signature (P = .008; Gene Set Enrichment Analysis) recently characterized in a mouse leukemia model. The HOX signature and EGFR expression were independent prognostic factors in multivariate analysis, adjusted for the O-6-methylguanine-DNA methyltransferase (MGMT) methylation status, a known predictive factor for benefit from temozolomide, and age. Better outcome was associated with gene clusters characterizing features of tumor-host interaction including tumor vascularization and cell adhesion, and innate immune response. CONCLUSION: This study provides first clinical evidence for the implication of a "glioma stem cell" or "self-renewal" phenotype in treatment resistance of glioblastoma. Biologic mechanisms identified here to be relevant for resistance will guide future targeted therapies and respective marker development for individualized treatment and patient selection.

Further concerns about self-assessment: are medical students aware of their progress in clinical skills during clerkship

Background: Medical students do not accurately self-assess their competence. However, little is known about the awareness of change of competence over time. The aim of this study was to evaluate if students are aware of their progress. Summary of work: Twenty-two fourth year medical students had self- and expert-assessments of their clinical skills in musculoskeletal medicine in an OSCE like station (4 point Likert scale) at the beginning (t0) and end (t1) of their eight weeks clerkship in internal medicine. Thirteen students were assigned to the intervention of a 6x1 hour practical examination course; nine took part in the regular clinical clerkship activities only and served as controls. Summary of results/Conclusions: The intervention students significantly improved their skills (from 2.78 ± 0.36 to 3.30 ± 0.36, p<0.05) in contrast to the control students (from 3.11 ± 0.58 to 2.83 ± 0.49, n.s.). At t0, 19 students, at t1 21 out of 22 students underestimated their competence. Correlations between the change of self- and expert-assessment were r=0.43, p<0.05 (all), r=0.47, n.s. (control) and r=-0.12, n.s. (intervention), respectively. Take-home message: Medical students improving their clinical skills by an interactive course in addition to their regular clerkship activities are not aware of their progress

Low self-esteem prospectively predicts depression in adolescence and young adulthood

Low self-esteem and depression are strongly correlated in cross-sectional studies, yet little is known about their prospective effects on each other. The vulnerability model hypothesizes that low self-esteem serves as a risk factor for depression, whereas the scar model hypothesizes that low self-esteem is an outcome, not a cause, of depression. To test these models, the authors used 2 large longitudinal data sets, each with 4 repeated assessments between the ages of 15 and 21 years and 18 and 21 years, respectively. Cross-lagged regression analyses indicated that low self-esteem predicted subsequent levels of depression, but depression did not predict subsequent levels of self-esteem. These findings held for both men and women and after controlling for content overlap between the self-esteem and depression scales. Thus, the results supported the vulnerability model, but not the scar model, of self-esteem and depression.

Disentangling the effects of low self-esteem and stressful events on depression: Findings from three longitudinal studies

Diathesis-stress models of depression suggest that low self-esteem and stressful events jointly influence the development of depressive affect. More specifically, the self-esteem buffering hypothesis states that, in the face of challenging life circumstances, individuals with low self-esteem are prone to depression because they lack sufficient coping resources, whereas those with high self-esteem are able to cope effectively and consequently avoid spiraling downward into depression. The authors used data from 3 longitudinal studies of adolescents and young adults, who were assessed 4 times over a 3-year period (Study 1; N = 359), 3 times over a 6-week period (Study 2; N = 249), and 4 times over a 6-year period (Study 3; N = 2,403). In all 3 studies, low self-esteem and stressful events independently predicted subsequent depression but did not interact in the prediction. Thus, the results did not support the self-esteem buffering hypothesis but suggest that low self-esteem and stressful events operate as independent risk factors for depression. In addition, the authors found evidence in all 3 studies that depression, but not low self-esteem, is reciprocally related to stressful events, suggesting that individuals high in depression are more inclined to subsequently experience stressful events.

Self-licensing effects on food choices

Recalling an egoistic act nudges people to choose healthy over unhealthy food options. Conversely, participants preferred unhealthy over healthy food options when they recalled an altruistic deed. Consistent with this choice pattern participants were willing to pay more for healthy than for unhealthy options. This experiment extends the self-licensing literature.

Veridicality of self-concept of strengths in male adolescents

Changes in physical self-concept and veridicality (i.e., the appropriateness of one’s self-perceptions to reality) during childhood and adolescence are related to performance in physical fi tness, exercise, and global self-esteem, particularly in male adolescents. This cross-sectional study examined the relation between the self-concept of strength and actual strength in groups of male adolescents ages 12 to 15 years. For this purpose, 889 male adolescents (M age = 13.2 yr., SD = 1.0) were questioned about their self-concept of strength, after which a test of strength was carried out. The results showed that the correlation between self- concept of strength and actual strength was higher in older (14- and 15-year-old) than younger (12- and 13-year-old) adolescents. There was a statistically signifi cant association between age group and veridicality, indicating that realistic self-concept is underrepresented among younger, but overrepresented among older adolescents. No association was found between the adolescents’ physical activity and veridicality. The consequences for further research on the development of veridicality in the physical domain are discussed.

Predictors of depressed mood 12 months after injury. Contribution of self-efficacy and social support

Abstract Purpose: There is evidence that depressed mood and perception of pain are related in patients with chronic illness. However, how individual resources such as self-efficacy and social support play a role in this association remains unclear. The aim of this study was to investigate the influence of both variables as either moderator or mediator. Method: In a longitudinal study, 274 injured workers (M = 43.24 years) were investigated. Data were collected on sociodemographics, depressed mood, pain, social support, and self-efficacy at three months post-injury, and depressed mood one year post-injury. Results: Hierarchical multiple linear regression analyses revealed that pain (β = 0.14; p < 0.01) and social support (β = -0.18; p < 0.001) were significant predictors of depressed mood. Self-efficacy moderated the relationship of pain (β = -0.12; p < 0.05) and depressed mood after one year. Lower self-efficacy in combination with pain had a stronger impact than higher self-efficacy and pain on depressed mood. Social support did not moderate the association. Conclusions: Self-efficacy for managing pain is important in the development of depressed mood. According to the results of this study, we suggest that the detection of low social support and low self-efficacy might be important in long-term rehabilitation process. Implications for Rehabilitation Risk for depressed mood one year after an accident is high: One in five workers report depressed mood. Protective factors for depressed mood in injured workers needs to be considered in the rehabilitation. Focusing on resources like social support and self-efficacy could be protective against depressed mood. The early detection of low social support and low self-efficacy might be important in long-term rehabilitation processes

Is low self-esteem a risk factor for depression? Findings from a longitudinal study of Mexican-origin youth

We examined the relation between low self-esteem and depression using longitudinal data from a sample of 674 Mexican-origin early adolescents who were assessed at age 10 and 12 years. Results supported the vulnerability model, which states that low self-esteem is a prospective risk factor for depression. Moreover, results suggested that the vulnerability effect of low self-esteem is driven, for the most part, by general evaluations of worth (i.e., global self-esteem), rather than by domain-specific evaluations of academic competence, physical appearance, and competence in peer relationships. The only domain-specific self-evaluation that showed a prospective effect on depression was honesty-trustworthiness. The vulnerability effect of low self-esteem held for male and female adolescents, for adolescents born in the United States versus Mexico, and across different levels of pubertal status. Finally, the vulnerability effect held when we controlled for several theoretically relevant 3rd variables (i.e., social support, maternal depression, stressful events, and relational victimization) and for interactive effects between self-esteem and the 3rd variables. The present study contributes to an emerging understanding of the link between self-esteem and depression and provides much needed data on the antecedents of depression in ethnic minority populations