Exposure to drinking water trihalomethanes and nitrate and the risk of brain tumours in young people.

Brain tumours (BTs) are one of the most frequent tumour types in young people. We explored the association between tap water, exposure to trihalomethanes (THM) and nitrate and neuroepithelial BT risk in young people. Analysis of tap water consumption were based on 321 cases and 919 appendicitis controls (10-24 years old) from 6 of the 14 participating countries in the international MOBI-Kids case-control study (2010-2016). Available historical residential tap water concentrations of THMs and nitrate, available from 3 countries for 86 cases and 352 controls and 85 cases and 343 for nitrate, respectively, were modelled and combined with the study subjects' personal consumption patterns to estimate ingestion and residential exposure levels in the study population (both pre- and postnatal). The mean age of participants was 16.6 years old and 56% were male. The highest levels and widest ranges for THMs were found in Spain (residential and ingested) and Italy and in Korea for nitrate. There was no association between BT and the amount of tap water consumed and the showering/bathing frequency. Odds Ratios (ORs) for BT in relation to both pre- and postnatal residential and ingestion levels of THMs were systematically below 1 (OR = 0.37 (0.08-1.73)) for postnatal average residential THMs higher than 66 µg/L. For nitrate, all ORs were above 1 (OR = 1.80 (0.91-3.55)) for postnatal average residential nitrate levels higher than 8.5 mg/L, with a suggestion of a trend of increased risk of neuroepithelial BTs with increasing residential nitrate levels in tap water, which appeared stronger in early in life. This, to our knowledge, is the first study on this topic in young people. Further research is required to clarify the observed associations.

Clinical presentation of young people (10-24 years old) with brain tumors: results from the international MOBI-Kids study.

INTRODUCTION: We used data from MOBI-Kids, a 14-country international collaborative case-control study of brain tumors (BTs), to study clinical characteristics of the tumors in older children (10 years or older), adolescents and young adults (up to the age of 24). METHODS: Information from clinical records was obtained for 899 BT cases, including signs and symptoms, symptom onset, diagnosis date, tumor type and location. RESULTS: Overall, 64% of all tumors were low-grade, 76% were neuroepithelial tumors and 62% gliomas. There were more males than females among neuroepithelial and embryonal tumor cases, but more females with meningeal tumors. The most frequent locations were cerebellum (22%) and frontal (16%) lobe. The most frequent symptom was headaches (60%), overall, as well as for gliomas, embryonal and 'non-neuroepithelial' tumors; it was convulsions/seizures for neuroepithelial tumors other than glioma, and visual signs and symptoms for meningiomas. A cluster analysis showed that headaches and nausea/vomiting was the only combination of symptoms that exceeded a cutoff of 50%, with a joint occurrence of 67%. Overall, the median time from first symptom to diagnosis was 1.42 months (IQR 0.53-4.80); it exceeded 1 year in 12% of cases, though no particular symptom was associated with exceptionally long or short delays. CONCLUSIONS: This is the largest clinical epidemiology study of BT in young people conducted so far. Many signs and symptoms were identified, dominated by headaches and nausea/vomiting. Diagnosis was generally rapid but in 12% diagnostic delay exceeded 1 year with none of the symptoms been associated with a distinctly long time until diagnosis.

Health trajectories of children with severe obesity attending a weight management program.

PURPOSE: The objective of the present study is to examine physical and mental health trajectories of change in youth with severe obesity attending a tertiary care weight management program. It was predicted that younger children would show favourable changes in body mass index (BMI), markers of cardiovascular health, quality of life, and mental health. METHODS: This 2-year longitudinal study examined health trajectories of children referred to a weight management program at a Canadian paediatric tertiary care centre from November 2010 to December 2013. Participants were 209 of 217 consecutive referred paediatric patients (families) aged 3 to 17 years who met criteria for severe obesity and consented to participate. To maximize generalizability of results, there were no exclusion criteria. Primary outcomes were children's quality of life and BMI. Secondary outcomes included anxiety, depression, and non-high-density lipoprotein cholesterol levels. RESULTS: The findings suggest an improvement in mental health, quality of life, and cardiometabolic health of children and adolescents of all ages over the 2 years of programming. These positive findings were consistent across gender, age, and distance to the program. BMI trajectory changes varied across age cohorts such that younger children showed more favourable outcomes. The retention rate over the 2 years was high at 82.9%. CONCLUSIONS: This is the first study to show improvements in both physical and mental health outcomes beyond 1 year in a tertiary care setting with a high-risk population of children and youth with severe obesity. Findings highlight the need to examine both mental and physical health outcomes beyond 1 year.

Recall of mobile phone usage and laterality in young people: The multinational Mobi-Expo study.

OBJECTIVE: To study recall of mobile phone usage, including laterality and hands-free use, in young people. METHODS: Actual mobile phone use was recorded among volunteers aged between 10 and 24 years from 12 countries by the software application XMobiSense and was compared with self-reported mobile phone use at 6 and 18 months after using the application. The application recorded number and duration of voice calls, number of text messages, amount of data transfer, laterality (% of call time the phone was near the right or left side of the head, or neither), and hands-free usage. After data cleaning, 466 participants were available for the main analyses (recorded vs. self-reported phone use after 6 months). RESULTS: Participants were on average 18.6 years old (IQR 15.2-21.8 years). The Spearman correlation coefficients between recorded and self-reported (after 6 months) number and duration of voice calls were 0.68 and 0.65, respectively. Number of calls was on average underestimated by the participants (adjusted geometric mean ratio (GMR) self-report/recorded = 0.52, 95% CI = 0.47-0.58), while duration of calls was overestimated (GMR=1.32, 95%, CI = 1.15-1.52). The ratios significantly differed by country, age, maternal educational level, and level of reported phone use, but not by time of the interview (6 vs. 18 months). Individuals who reported low mobile phone use underestimated their use, while individuals who reported the highest level of phone use were more likely to overestimate their use. Individuals who reported using the phone mainly on the right side of the head used it more on the right (71.1%) than the left (28.9%) side. Self-reported left side users, however, used the phone only slightly more on the left (53.3%) than the right (46.7%) side. Recorded percentage hands-free use (headset, speaker mode, Bluetooth) increased with increasing self-reported frequency of hands-free device usage. Frequent (≥50% of call time) reported headset or speaker mode use corresponded with 17.1% and 17.2% of total call time, respectively, that was recorded as hands-free use. DISCUSSION: These results indicate that young people can recall phone use moderately well, with recall depending on the amount of phone use and participants' characteristics. The obtained information can be used to calibrate self-reported mobile use to improve estimation of radiofrequency exposure from mobile phones.

Correction: Barriers and enablers for adopting lifestyle behavior changes in adolescents with obesity: A multi-centre, qualitative study.

[This corrects the article DOI: 10.1371/journal.pone.0209219.].

Graduate students' perceptions of contrapower sexual harassment.

This study compared the perceptions of 172 graduate students to traditional versus contrapower sexual harassment. Graduate students are a unique sample due to their dual role as a student and a teacher. After controlling for attitudes toward feminism and sexual harassment, participants viewed contrapower sexual harassment as less indicative of sexual harassment than traditional sexual harassment. Those with teaching experience perceived the scenarios provided as more indicative of sexual harassment than participants without teaching experience, and this effect was magnified for males. These findings suggest that people take sexual harassment less seriously in contrapower sexual harassment than in traditional sexual harassment. Furthermore, it is possible that teaching experience makes graduate students more aware of the complicated power differentials involved in classroom settings.

Barriers and enablers for adopting lifestyle behavior changes in adolescents with obesity: A multi-centre, qualitative study.

BACKGROUND: Many adolescents with obesity do not meet recommendations for nutrition, physical and sedentary activities, and sleep habits, all of which can influence weight management. OBJECTIVE: To explore barriers and enablers that influenced the adoption of lifestyle behavior changes among adolescents receiving multidisciplinary clinical care for pediatric weight management. METHODS: In this multi-centre, qualitative description study, we used purposeful sampling to recruit 13-17 year olds (body mass index ≥85th percentile) enrolled in one of two pediatric weight management clinics in Edmonton and Ottawa, Canada. Adolescents participated in one-on-one, in-person, semi-structured interviews in English or French. Interviews lasted 30-60 minutes, were audio-recorded, transcribed verbatim, and managed using NVivo 11. Data were triangulated using transcripts, field notes, and memos and analyzed by two independent researchers using inductive, semantic thematic analysis. RESULTS: In total, 19 adolescents (12 Anglophone and 7 Francophone; 15.1±1.7 years old; 3.5±0.6 BMI z-score; n = 11 female; n = 13 Caucasian) participated. Adolescents reported diverse barriers to and enablers of healthy nutrition, physical and sedentary activities, and sleep habits, which we organized into the following themes: physiological mechanisms and physical health status, self-regulation for behavior change, controllability and competence beliefs, social relationships and interactions, and accessibility to and availability of opportunities for lifestyle enhancement. Across these themes and lifestyle areas, we identified three shared barriers and/or enablers, including the degree of controllability, the impact of mental health, and social pressures related to weight management. CONCLUSIONS: This research provides evidence that can be used to tailor interventions and health services delivery, including a focus on psychosocial well-being, to support adolescents with obesity in making and maintaining healthy lifestyle behavior changes.

Patterns of cellular phone use among young people in 12 countries: Implications for RF exposure.

Characterizing exposure to radiofrequency (RF) fields from wireless telecommunications technologies during childhood and adolescence is a research priority in investigating the health effects of RF. The Mobi-Expo study aimed to describe characteristics and determinants of cellular phone use in 534 young people (10-24years) in 12 countries. The study used a specifically designed software application installed on smartphones to collect data on the use of wireless telecommunications devices within this age group. The role of gender, age, maternal education, calendar period, and country was evaluated through multivariate models mutually adjusting for all variables. Call number and duration were higher among females compared to males (geometric mean (GM) ratio 1.17 and 1.42, respectively), among 20-24year olds compared to 10-14year olds (GM ratio 2.09 and 4.40, respectively), and among lowest compared to highest social classes (GM ratio 1.52 and 1.58, respectively). The number of SMS was higher in females (GM ratio 1.46) and the middle age group (15-19year olds: GM ratio 2.21 compared to 10-14year olds) and decreased over time. Data use was highest in the oldest age group, whereas Wi-Fi use was highest in the middle age group. Both data and Wi-Fi use increased over time. Large differences in the number and duration of calls, SMS, and data/Wi-Fi use were seen by country, with country and age accounting for up to 50% of the variance. Hands-free and laterality of use did not show significant differences by sex, age, education, study period, or country. Although limited by a convenience sample, these results provide valuable insights to the design, analysis, and interpretation of future epidemiological studies concerning the health effects of exposure resulting from cellular phone use in young people. In addition, the information provided by this research may be used to design strategies to minimize RF exposure.

The MOBI-Kids Study Protocol: Challenges in Assessing Childhood and Adolescent Exposure to Electromagnetic Fields from Wireless Telecommunication Technologies and Possible Association with Brain Tumor Risk.

The rapid increase in mobile phone use in young people has generated concern about possible health effects of exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF). MOBI-Kids, a multinational case-control study, investigates the potential effects of childhood and adolescent exposure to EMF from mobile communications technologies on brain tumor risk in 14 countries. The study, which aims to include approximately 1,000 brain tumor cases aged 10-24 years and two individually matched controls for each case, follows a common protocol and builds upon the methodological experience of the INTERPHONE study. The design and conduct of a study on EMF exposure and brain tumor risk in young people in a large number of countries is complex and poses methodological challenges. This manuscript discusses the design of MOBI-Kids and describes the challenges and approaches chosen to address them, including: (1) the choice of controls operated for suspected appendicitis, to reduce potential selection bias related to low response rates among population controls; (2) investigating a young study population spanning a relatively wide age range; (3) conducting a large, multinational epidemiological study, while adhering to increasingly stricter ethics requirements; (4) investigating a rare and potentially fatal disease; and (5) assessing exposure to EMF from communication technologies. Our experience in thus far developing and implementing the study protocol indicates that MOBI-Kids is feasible and will generate results that will contribute to the understanding of potential brain tumor risks associated with use of mobile phones and other wireless communications technologies among young people.