To Örebro University

Background: To study the association between use of wireless phones and meningioma. Methods: We performed a case-control study on brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age was used to each case. Here we report on meningioma cases including all available controls. Exposures were assessed by a questionnaire. Unconditional logistic regression analysis was performed. Results: In total 709 meningioma cases and 1,368 control subjects answered the questionnaire. Mobile phone use in total produced odds ratio (OR) = 1.0, 95% confidence interval (CI) = 0.7-1.4 and cordless phone use gave OR = 1.1, 95% CI = 0.8-1.5. The risk increased statistically significant per 100 h of cumulative use and highest OR was found in the fourth quartile (>2,376 hours) of cumulative use for all studied phone types. There was no statistically significant increased risk for ipsilateral mobile or cordless phone use, for meningioma in the temporal lobe or per year of latency. Tumour volume was not related to latency or cumulative use in hours of wireless phones. Conclusions: No conclusive evidence of an association between use of mobile and cordless phones and meningioma was found. An indication of increased risk was seen in the group with highest cumulative use but was not supported by statistically significant increasing risk with latency. Results for even longer latency periods of wireless phone use than in this study are desirable.

The purpose of this paper is to describe how Chinese national adolescent mental health policy is translated into local plans and practice by means of the theoretical perspective of the policy triangle. Document analysis of national, provincial and local policy documents and semi-structured interviews with local policy actors were performed. National policies were implemented by a top-down process. The ministries were strong policy-makers on the national level, while the policy actors at the local level were mainly found in the educational sector. The content of the policy actions was moral education, knowledge dissemination and learning, rather than counselling and treatment.

Background: In epidemiological surveillance of mental health there is good reason to also include scales that measure the presence of well-being rather than merely symptoms of ill health. The Mental Health Continuum-Short Form (MHC-SF) is a self-reported scale to measure emotional, psychological and social well-being and conduct categorical diagnosis of positive mental health. This particular instrument includes the three core components of the World Health Organization's definition of mental health and had previously not been psychometrically evaluated on adolescents in China.

Methods: In total 5,399 students (51.1% female) from schools in the urban areas of Weifang in China were included in the study (mean age = 15.13, SD = 1.56). Participants completed a comprehensive questionnaire with several scales, among them the MHC-SF. Statistical analyses to evaluate reliability, structural validity, measurement invariance, presence of floor and ceiling effects and to some extent external validity of the MHC-SF were carried out.

Results: The Cronbach's α coefficients for sub-scales as well as the total scale were all above 0.80 indicating good reliability. Confirmative factor analysis confirmed the three-dimensional structure of the Chinese version of MHC-SF and supported the configural and metric invariance across gender and age. Noteworthy ceiling effects were observed for single items and sub-scales although not for the total scale. More importantly, observed floor effects were negligible. The stronger correlation found between MHC-SF and Minneapolis-Manchester Quality of Life Instrument (as measure of positive mental health) than between MHC-SF and Hospital Anxiety Depression Scale (as measure of mental illness and distress) yielded support for external validity.

Conclusion: In conclusion, the main findings of this study are in line with studies from other countries that evaluated the psychometric properties of the MHC-SF and show that this instrument, that includes the three core components of the WHO definition of mental health, is useful in assessing positive adolescent mental health also in China.

Background: Studies investigating the prevalence of positive mental health and its correlates are still scarce compared to the studies on mental disorders, although there is growing interest of assessing positive mental health in adolescents. So far, no other study examining the prevalence and determinants of positive mental health in Chinese adolescents has been found. The purpose of this study was to assess the prevalence and correlates of positive mental health in Chinese adolescents.

Methods: This cross-sectional study used a questionnaire including Mental Health Continuum-Short Form (MHC-SF) and items regarding multiple aspects of adolescent life. The sample involved a total of 5399 students from grade 8 and 10 in Weifang, China. Multivariate Logistic regression analyses were performed to evaluate the associations between potential indicators regarding socio-economic situations, life style, social support and school life and positive mental health and calculate odds ratios and 95% confidence intervals.

Results: More than half (57.4%) of the participants were diagnosed as flourishing. The correlated factors of positive mental health in regression models included gender, perceived family economy, the occurrence of sibling(s), satisfaction of self-appearance, physical activity, sleep quality, stress, social trust, desire to learn, support from teachers and parents as well as whether being bullied at school (OR ranging from 1.23 to 2.75). The Hosmer-Lemeshow p-value for the final regression model (0.45) indicated adequate model fit.

Conclusion: This study gives the first overview on prevalence and correlates of positive mental health in Chinese adolescents. The prevalence of positive mental health in Chinese adolescents is higher than reported in most of the previous studies also using MHC-SF. Our findings suggest that adolescents with advantageous socio-economic situations, life style, social support and school life are experiencing better positive mental health than others.

We evaluated long-term use of mobile phones and the risk for brain tumours in case-control studies published so far on this issue. We identified ten studies on glioma and meta-analysis yielded OR = 0.9, 95% CI = 0.8-1.1. Latency period of > or =10-years gave OR = 1.2, 95% CI = 0.8-1.9 based on six studies, for ipsilateral use (same side as tumour) OR = 2.0, 95% CI = 1.2-3.4 (four studies), but contralateral use did not increase the risk significantly, OR = 1.1, 95% CI = 0.6-2.0. Meta-analysis of nine studies on acoustic neuroma gave OR = 0.9, 95% CI = 0.7-1.1 increasing to OR = 1.3, 95% CI = 0.6-2.8 using > or =10-years latency period (four studies). Ipsilateral use gave OR = 2.4, 95% CI = 1.1-5.3 and contra-lateral OR = 1.2, 95% CI = 0.7-2.2 in the > or =10-years latency period group (three studies). Seven studies gave results for meningioma yielding overall OR = 0.8, 95% CI = 0.7-0.99. Using > or =10-years latency period OR = 1.3, 95% CI = 0.9-1.8 was calculated (four studies) increasing to OR = 1.7, 95% CI = 0.99-3.1 for ipsilateral use and OR = 1.0, 95% CI = 0.3-3.1 for contralateral use (two studies). We conclude that this meta-analysis gave a consistent pattern of an association between mobile phone use and ipsilateral glioma and acoustic neuroma using > or =10-years latency period.

Electromagnetic hypersensitivity (EHS) is used for a variety of subjective symptoms related to exposure to electromagnetic fields (EMF). The aim of this pilot study was to analyze the concentrations of certain persistent organic pollutants (POPs) in subjects with self-reported EHS. In total, 13 EHS subjects and 21 controls were included, all female. The concentration of several POPs was higher in EHS subjects than in controls. Lower concentrations were found for hexachlorobenzene and two types of chlordanes. The only significantly increased odds ratios (ORs) were found for polybrominated diphenyl ether (PBDE) #47 yielding OR=11.7, 95% confidence interval (CI)=1.45-94.7 and the chlordane metabolite MC6 with OR=11.2, 95% CI=1.18-106. The results were based on low numbers and must be interpreted with caution. This hypothesis generating study indicates the necessity of a larger investigation on this issue.

Previous studies have shown a consistent association between long-term use of mobile and cordless phones and glioma and acoustic neuroma, but not for meningioma. When used these phones emit radiofrequency electromagnetic fields (RF-EMFs) and the brain is the main target organ for the hand-held phone. The International Agency for Research on Cancer (IARC) classified in May, 2011 RF-EMF as a group 2B, i.e. a possible' human carcinogen. The aim of this study was to further explore the relationship between especially long-term (>10 years) use of wireless phones and the development of malignant brain tumours. We conducted a new case-control study of brain tumour cases of both genders aged 18-75 years and diagnosed during 2007-2009. One population-based control matched on gender and age (within 5 years) was used to each case. Here, we report on malignant cases including all available controls. Exposures on e.g. use of mobile phones and cordless phones were assessed by a self-administered questionnaire. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index using the whole control sample. Of the cases with a malignant brain tumour, 87% (n=593) participated, and 85% (n=1,368) of controls in the whole study answered the questionnaire. The odds ratio (OR) for mobile phone use of the analogue type was 1.8, 95% confidence interval (CI)=1.04-3.3, increasing with >25 years of latency (time since first exposure) to an OR=3.3, 95% CI=1.6-6.9. Digital 2G mobile phone use rendered an OR=1.6, 95% CI=0.996-2.7, increasing with latency >15-20 years to an OR=2.1, 95% CI=1.2-3.6. The results for cordless phone use were OR=1.7, 95% CI=1.1-2.9, and, for latency of 15-20 years, the OR=2.1, 95% CI=1.2-3.8. Few participants had used a cordless phone for >20-25 years. Digital type of wireless phones (2G and 3G mobile phones, cordless phones) gave increased risk with latency >1-5 years, then a lower risk in the following latency groups, but again increasing risk with latency >15-20 years. Ipsilateral use resulted in a higher risk than contralateral mobile and cordless phone use. Higher ORs were calculated for tumours in the temporal and overlapping lobes. Using the meningioma cases in the same study as reference entity gave somewhat higher ORs indicating that the results were unlikely to be explained by recall or observational bias. This study confirmed previous results of an association between mobile and cordless phone use and malignant brain tumours. These findings provide support for the hypothesis that RF-EMFs play a role both in the initiation and promotion stages of carcinogenesis.

We previously conducted a case-control study of acoustic neuroma. Subjects of both genders aged 20-80 years, diagnosed during 1997-2003 in parts of Sweden, were included, and the results were published. We have since made a further study for the time period 2007-2009 including both men and women aged 18-75 years selected from throughout the country. These new results for acoustic neuroma have not been published to date. Similar methods were used for both study periods. In each, one population-based control, matched on gender and age (within five years), was identified from the Swedish Population Registry. Exposures were assessed by a self-administered questionnaire supplemented by a phone interview. Since the number of acoustic neuroma cases in the new study was low we now present pooled results from both study periods based on 316 participating cases and 3,530 controls. Unconditional logistic regression analysis was performed, adjusting for age, gender, year of diagnosis and socio-economic index (SEI). Use of mobile phones of the analogue type gave odds ratio (OR) = 2.9, 95% confidence interval (CI) = 2.0-4.3, increasing with >20 years latency (time since first exposure) to OR = 7.7, 95% CI = 2.8-21. Digital 20 mobile phone use gave OR = 1.5, 95% CI = 1.1-2.1, increasing with latency >15 years to an OR = 1.8, 95% CI = 0.8-4.2. The results for cordless phone use were OR = 1.5, 95% CI = 1.1-2.1, and, for latency of >20 years, OR = 6.5, 95% CI = 1.7-26. Digital type wireless phones (20 and 3G mobile phones and cordless phones) gave OR = 1.5, 95% CI = 1.1-2.0 increasing to OR = 8.1,95% CI = 2.0-32 with latency >20 years. For total wireless phone use, the highest risk was calculated for the longest latency time >20 years: OR = 4.4, 95% CI = 2.2-9.0. Several of the calculations in the long latency category were based on low numbers of exposed cases. Ipsilateral use resulted in a higher risk than contralateral for both mobile and cordless phones. OR increased per 100 h cumulative use and per year of latency for mobile phones and cordless phones, though the increase was not statistically significant for cordless phones. The percentage tumour volume increased per year of latency and per 100 h of cumulative use, statistically significant for analogue phones. This study confirmed previous results demonstrating an association between mobile and cordless phone use and acoustic neuroma.

AIM: To evaluate brain tumour risk among long-term users of cellular telephones. METHODS: Two cohort studies and 16 case-control studies on this topic were identified. Data were scrutinised for use of mobile phone for > or =10 years and ipsilateral exposure if presented. RESULTS: The cohort study was of limited value due to methodological shortcomings in the study. Of the 16 case-control studies, 11 gave results for > or =10 years' use or latency period. Most of these results were based on low numbers. An association with acoustic neuroma was found in four studies in the group with at least 10 years' use of a mobile phone. No risk was found in one study, but the tumour size was significantly larger among users. Six studies gave results for malignant brain tumours in that latency group. All gave increased odd ratios (OR), especially for ipsilateral exposure. In a meta-analysis, ipsilateral cell phone use for acoustic neuroma was OR = 2.4 (95% CI 1.1 to 5.3) and OR = 2.0, (1.2 to 3.4) for glioma using a tumour latency period of > or =10 years. CONCLUSIONS: Results from present studies on use of mobile phones for > or =10 years give a consistent pattern of increased risk for acoustic neuroma and glioma. The risk is highest for ipsilateral exposure.

BACKGROUND: The use of cellular and cordless telephones has increased dramatically during the last decade. There is concern of health problems such as malignant diseases due to microwave exposure during the use of these devices. The brain is the main target organ. METHODS: Since the second part of the 1990's we have performed six case-control studies on this topic encompassing use of both cellular and cordless phones as well as other exposures. Three of the studies concerned brain tumours, one salivary gland tumours, one non-Hodgkin lymphoma (NHL) and one testicular cancer. Exposure was assessed by self-administered questionnaires. RESULTS: Regarding acoustic neuroma analogue cellular phones yielded odds ratio (OR) = 2.9, 95 % confidence interval (CI) = 2.0-4.3, digital cellular phones OR = 1.5, 95 % CI = 1.1-2.1 and cordless phones OR = 1.5, 95 % CI = 1.04-2.0. The corresponding results were for astrocytoma grade III-IV OR = 1.7, 95 % CI = 1.3-2.3; OR = 1.5, 95 % CI = 1.2-1.9 and OR = 1.5, 95 % CI = 1.1-1.9, respectively. The ORs increased with latency period with highest estimates using > 10 years time period from first use of these phone types. Lower ORs were calculated for astrocytoma grade I-II. No association was found with salivary gland tumours, NHL or testicular cancer although an association with NHL of T-cell type could not be ruled out. CONCLUSION: We found for all studied phone types an increased risk for brain tumours, mainly acoustic neuroma and malignant brain tumours. OR increased with latency period, especially for astrocytoma grade III-IV. No consistent pattern of an increased risk was found for salivary gland tumours, NHL, or testicular cancer.

In this cross-sectional study, we aimed to I) investigate the dual-factor model of mental health by forming and describing four participant groups and II) examine associations between mental health status and background factors, school-related factors, stress, and resilience among adolescents in a community population in Sweden. Data were collected through a survey completed by 2,208 students in lower and upper secondary school on the Swedish island of Gotland. After missing data were removed, a total of 1,833 participants were included in the study. The survey included the Mental Health Continuum Short Form (MHC-SF) for the assessment of mental well-being and the Strengths and Difficulties Questionnaire (SDQ) for the assessment of mental health problems. These two measures were combined into a dual-factor model, forming four mental health status subgroups: Vulnerable (47.5%), Complete mental health (36.2%), Troubled (13.9%), and Symptomatic but content (2.5%). Associations between these groups were explored regarding background factors, school-related factors, stress, and resilience through chi-squared tests and logistic regressions. Girls (OR: 1.88) and participants with high stress levels (OR: 2.23) had elevated odds for Vulnerable mental health status, whereas higher resilience (OR: 0.87) and subjective social status in school (OR: 0.76) were factors associated with reduced odds for this mental health status classification. Female gender (OR: 5.02) was also associated with Troubled mental health status. Similarly, a high level of stress (ORs: 4.08 and 11.36) was associated with Symptomatic but content and Troubled mental health status, and participants with higher levels of resilience had decreased odds for being classified into these groups (ORs: 0.88 and 0.81). The findings highlight the importance of interventions to increase resilience, reduce stress, and address stereotypic gender norms as well as social status hierarchies to support adolescents' mental health.

Recent years have seen a rapid increase in the use of wireless telephones, yet little systematic data exist on the actual use of such devices in the general population. Mobile and cordless telephones emit radiofrequency fields (RF) raising concern about possible adverse health effects. As children and teenagers might be more vulnerable and have longer expected lifetime exposures to RF from these devices than adults, who started to use them later in life, they are a group of special concern. The aims of papers I and II in this thesis were to increase our knowledge of use of wireless telephones in the age group of 7-19 years, to study what factors could explain such use; and furthermore, whether the use among the 15-19 year group was associated with self-reported health symptoms and well-being. For collection of data a posted questionnaire was used. Among the 7-14 group (n=1423) nearly all had access to a mobile telephone, a cordless telephone or both, although the percentage of regular users was rather low, totally. Use of wireless telephones increased with age and was more common among girls than boys, especially among the 15-19 year group (n=1269). Relatively few regular users of mobile telephones reported to use a handsfree. Besides age and gender the probability of using either a mobile or cordless telephone was associated mainly with watching TV extensively and below average household income. Regular users more often had health symptoms and reported poorer perceived health than did non-regular users. However, the latter should be interpreted with caution since bias and chance findings due to multiple testing might have influenced the results. Methodologically more sophisticated studies are needed to confirm these results and also investigate directions of possible associations. The aim of papers III-V was to investigate the potential effects of wireless telephone emissions on the integrity of the blood-brain barrier (BBB) and the blood-cerebrospinal fluid barrier (BCSFB) using biomarkers. In paper III – an observational study on adults (n=314) – use of mobile and cordless telephones combined was not associated with serum levels of S100B as a marker of BBB disruption. Analyzing the different telephone types separately yielded a weak association of decreasing concentrations with minutes since last use of cordless telephone on the day of leaving blood and a statistically significant association of higher concentrations the more years since first use of a 3G-telephone. However, the latter is probably a result of chance or confounding. Paper IV comprised the same data set as in paper III using serum transthyretin (TTR) as a marker of BCSFB dysfunction. The main finding was that the number of years since first use of mobile and cordless telephones combined was statistically significantly associated with higher serum levels of TTR regardless of how much each telephone type had been used. However, extra-cerebral sources of TTR might have confounded the results, if associated with exposure. Paper V was an experimental study investigating a possible short-term effect of an 890-megahertz mobile phone-like exposure on the BBB and the BCSFB of 41 volunteers. Repeated blood sampling before and after the provocation showed no statistically significant increase in the serum levels of S100B, while for TTR a small but statistically significant increase was seen in the final blood sample 60 minutes after the end of the provocation as compared to the prior sample taken immediately after provocation. The possible clinical significance of this finding is unknown. Larger randomized studies that employ use of additional more brain-specific markers and multiple exposure conditions are needed.

Folkhälsan i Sverige är generellt sett god men inte jämlikt fördelad. Medan detfinns en del kunskap om skillnader i psykiska besvär och psykisk sjukdom mellan grupper är underlaget betydligt tunnare när det gäller skillnader i förekomst av (positiv) psykisk hälsa, som har ett värde i sig. Den nationella kommissionen för jämlik hälsa lyfter fram åtta områden som är viktiga i arbetet med att utjämna de påverkbara hälsoskillnaderna. Ett av dessa är likvärdiga villkor och möjligheter under det tidiga livet och i skolan. Av detta följer att barn och ungdomar blir särskilt viktiga att studera för att förstå skillnader i psykisk hälsa så att verknings-fulla insatser kan utformas. Syftet med den här studien är att undersöka skillnader ipsykisk hälsa bland ungdomar. Rapporten baseras på den återkommande tvärsnittsstudien Liv och hälsa ung Västmanland, undersökningsåren 2014 och 2017. Datainsamling genomfördes på skoltid och under skrivningslikna nde förhållanden. Studiepopulationen bestod av ungdomar i årskurs 9 i grundskolan och årskurs 2 i gymnasiet. Skillnaderna i psykisk hälsa studerades utifrån: socioekonomisk status (SES), kön, ålder, sexuell läggning, födelseland och fem typer av funktionsnedsättningar. Psykisk hälsa mättes med instrumentet Mental Health Continuum – Short Form. Deltagandet i berörda årkurser var 78 procent 2014 och 76 procent 2017, vilket motsvarar totalt 7 637 ungdomar varav 52 procent var tjejer.Studien visar att det finns statistiskt signifikanta skillnader i psykisk hälsa inomfyra av sex studerade indelningsgrunder. Av dessa är det skillnader mellan grupper med olika SES som är av sådan storlek att de kan anses ha praktisk betydelse. Skillnader inom övriga indelningsgrunder – justerade bland annat för SES – är små eller mycket små men kan tillsammans få praktisk betydelse. Det gäller t.ex. de samlade skillnaderna inom kön, sexuell läggning och funktionsnedsättningar såsom add, adhd och Tourettes. Studien visar också signifikanta skillnader i psykisk hälsa mellan de två mättillfällena. Totalt sett är dessa skillnader att betrakta som mycket små. Ändå är de bekymrande eftersom de kan kopplas till fyra funktionsnedsättningar inom vilka ojämlikheten i psykisk hälsa ser ut att ha ökat mellan 2014 och 2017. Visserligen finns det metodologiska skillnader mellan de två undersökningsåren men det är inte troligt att ökningarna beror på dem. Åtgärder för att reducera skillnader i psykisk hälsa bör anpassas så att de i omfattning och utformning tar särskild hänsyn till grupper med låg SES eller dem med låg SES i kombination med kön (tjej), sexuell läggning ( icke-heterosexuell) och funktionsnedsättningar i form av add, adhd, Tourettes eller liknande.

Whether low-intensity non-thermal microwave radiation alters the integrity of the blood-brain barrier has been debated since the late 1970s, yet no experimental study has been carried out on humans. The aim of this study was to test, using peripheral markers, whether exposure to a mobile phone-like signal alters the integrity of the human blood-brain and blood-cerebrospinal fluid barriers. A provocation study was carried out that exposed 41 volunteers to a 30 min GSM 890 MHz signal with an average specific energy absorption rate distribution of 1.0 W/kg in the temporal area of the head as measured over any 1g of contiguous tissue. The outcome was assessed by changes in serum concentrations of two putative markers of brain barrier integrity, S100B and transthyretin. Repeated blood sampling before and after the provocation showed no statistically significant increase in the serum levels of S100B, while for transthyretin a statistically significant increase was seen in the final blood sample 60 min after the end of the provocation as compared to the prior sample taken immediately after provocation (p=0.02). The clinical significance of this finding, if any, is unknown. Further randomized studies with use of additional more brain specific markers are needed.

For some time it has been investigated whether low-intensity non-thermal microwave radiation from mobile phones adversely affects the mammalian blood-brain barrier (BBB). All such studies except one have been either in vitro or experimental animal studies. The one carried out on humans showed a statistically significant increase in serum transthyretin (TTR) 60 min after finishing of a 30-min microwave exposure session. The aim of the present study was to follow up on the finding of the previous one using a better study design. Using biomarkers analyzed in blood serum before and after the exposure this single blinded randomized counterbalanced study, including 24 healthy subjects aged 18-30 years that all underwent three exposure conditions (SAR(10G) = 2 W/kg, SAR(10G) = 0.2 W/kg, sham), tested whether microwaves from an 890-MHz phone-like signal give acute effects on the integrity of brain-shielding barriers. Over time, statistically significant variations were found for two of the three biomarkers (TTR; beta-trace protein); however, no such difference was found between the different exposure conditions nor was there any interaction between exposure condition and time of blood sampling. In conclusion this study failed to show any acute clinically or statistically significant effect of short term microwave exposure on the serum levels of S100 beta, TTR and b-trace protein with a follow up limited to two hours. The study was hampered by the fact that all study persons were regular wireless phone users and thus not naive as to microwave exposure. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

BACKGROUND: Whether low-intensity radiofrequency radiation damages the blood-brain barrier has long been debated, but little or no consideration has been given to the blood-cerebrospinal fluid barrier. In this cross-sectional study we tested whether long-term and/or short-term use of wireless telephones was associated with changes in the serum transthyretin level, indicating altered transthyretin concentration in the cerebrospinal fluid, possibly reflecting an effect of radiation. METHODS: One thousand subjects, 500 of each sex aged 18-65 years, were randomly recruited using the population registry. Data on wireless telephone use were assessed by a postal questionnaire and blood samples were analyzed for serum transthyretin concentrations determined by standard immunonephelometric techniques on a BN Prospec instrument. RESULTS: The response rate was 31.4%. Logistic regression of dichotomized TTR serum levels with a cut-point of 0.31 g/l on wireless telephone use yielded increased odds ratios that were statistically not significant. Linear regression of time since first use overall and on the day that blood was withdrawn gave different results for males and females: for men significantly higher serum concentrations of TTR were seen the longer an analogue telephone or a mobile and cordless desktop telephone combined had been used, and in contrast, significantly lower serum levels were seen the longer an UMTS telephone had been used. Adjustment for fractions of use of the different telephone types did not modify the effect for cumulative use or years since first use for mobile telephone and DECT, combined. For women, linear regression gave a significant association for short-term use of mobile and cordless telephones combined, indicating that the sooner blood was withdrawn after the most recent telephone call, the higher the expected transthyretin concentration. CONCLUSION: In this hypothesis-generating descriptive study time since first use of mobile telephones and DECT combined was significantly associated with higher TTR levels regardless of how much each telephone type had been used. Regarding short-term use, significantly higher TTR concentrations were seen in women the sooner blood was withdrawn after the most recent telephone call on that day.

BACKGROUND: Despite the last years of rapid increase in use of wireless phones little data on the use of these devices has been systematically assessed among young persons. The aim of this descriptive cross-sectional study was to assess use of wireless phones and to study such use in relation to explanatory factors and self-reported health symptoms. METHODS: A postal questionnaire comprising 8 pages of 27 questions with 75 items in total was sent to 2000 Swedish adolescents aged 15-19 years and selected from the population registry using a stratified sampling scheme. RESULTS: The questionnaire was answered by 63.5% of the study subjects. Most participants reported access to a mobile phone (99.6%) and use increased with age; 55.6% of the 15-year-olds and 82.2% of the 19-year-olds were regular users. Girls generally reported more frequent use than boys. Use of wired hands-free equipment 'anytime' was reported by 17.4%. Cordless phones were used by 81.9%, and 67.3% were regular users. Watching TV increased the odds ratio for use of wireless phones, adjusted for age and gender. Some of the most frequently reported health complaints were tiredness, stress, headache, anxiety, concentration difficulties and sleep disturbances. Regular users of wireless phones had health symptoms more often and reported poorer perceived health than less frequent users. CONCLUSION: Almost all adolescence in this study used a wireless phone, girls more than boys. The most frequent use was seen among the older adolescents, and those who watched TV extensively. The study further showed that perceived health and certain health symptoms seemed to be related to the use of wireless phones. However, this part of the investigation was explorative and should therefore be interpreted with caution since bias and chance findings due to multiple testing might have influenced the results. Potentially this study will stimulate more sophisticated studies that may also investigate directions of associations and whether, or to what degree, any mediation factors are involved.

BACKGROUND: Since the late 1970s, experimental animal studies have been carried out on the possible effects of low-intensive radiofrequency fields on the blood-brain barrier (BBB), but no epidemiological study has been published to date. OBJECTIVE: Using serum S100B as a putative marker of BBB dysfunction we performed a descriptive cross-sectional study to investigate whether protein levels were higher among frequent than non-frequent users of mobile and cordless desktop phones. METHOD: One thousand subjects, 500 of each sex aged 18-65 years, were randomly recruited using the population registry. Data on wireless phone use were assessed by a postal questionnaire and blood samples were analyzed for S100B. RESULTS: The response rate was 31.4%. The results from logistic and linear regression analyses were statistically insignificant, with one exception: the linear regression analysis of latency for UMTS use, which after stratifying on gender remained significant only for men (p = 0.01; n = 31). A low p-value (0.052) was obtained for use of cordless phone (n = 98) prior to giving the blood samples indicating a weak negative association. Total use of mobile and cordless phones over time yielded odds ratio (OR) 0.8 and 95% confidence interval (CI) 0.3-2.0 and use on the same day as giving blood yielded OR=1.1, CI=0.4-2.8. CONCLUSIONS: This study failed to show that long- or short-term use of wireless telephones was associated with elevated levels of serum S100B as a marker of BBB integrity. The finding regarding latency of UMTS use may be interesting but it is based on small numbers. Generally, S100B levels were low and to determine whether this association - if causal - is clinically relevant, larger studies with sufficient follow-up are needed.

BACKGROUND: Recent years have seen a rapid increase in the use of mobile phones and other sources of microwave radiation, raising concerns about possible adverse health effects. As children have longer expected lifetime exposures to microwaves from these devices than adults, who started to use them later in life, they are a group of special interest. METHODS: We performed a population-based study to assess ownership and use of mobile phones and cordless phones among children aged 7-14 years. A questionnaire comprising 24 questions was sent to 2000 persons selected from the Swedish population registry using a stratified sampling scheme. RESULTS: The response rate was 71.2%. Overall, 79.1% of the respondents reported mobile phone access, and 26.7% of them talked for 2 minutes or more per day. Of those who reported mobile phone access, only 5.9% reported use of hands-free equipment. Use of cordless phones was reported by 83.8% of the respondents and 38.5% of them talked for 5 minutes or more per day. Girls generally reported more frequent use than boys. CONCLUSION: This study showed that most children had access to and used mobile and cordless phones early in life and that there was a rapid increase in use with age. It also showed very low use of hands-free equipment among children with mobile phone access, and finally that girls talked significantly more minutes per day using mobile and cordless phones than boys did.

The Mental Health Continuum - Short form (MHC-SF) is a self-report measure that has been increasingly used to monitor mental well-being at the population level. The aim of this study was to evaluate, for the first time, the psychometric properties of the MHC-SF in a population of Swedish adolescents. First, the evaluation was performed by examining face validity and test-retest reliability obtained in a pre-study. Then using data from the Survey of Adolescent Life in Vestmanland 2020 (n = 3880) we performed confirmatory factor analysis on different factor structures based on theory and previous research. Model-based estimates were calculated for assessing the internal reliability of the factor structure with the best fit. Convergent validity was assessed by bivariate as well as model-based correlations, and test-retest reliability was evaluated by intra-class correlation coefficients. The results show that the MHC-SF is best described with a bifactor model consisting of a dominant general well-being factor and three specific group factors of emotional, social and psychological well-being. Its overall reliability was high to very high, while the reliability of its subscales was low. A practical implication of the latter is that the subcales should not be used on their own because they are more likely to reliably measure the general well-being factor than the specific group factors. Test-retest reliability of the total scale was acceptable, and convergent validity was supported. In conclusion, we consider the Swedish MHC-SF to be a psychometrically sound instrument for monitoring overall mental well-being in Swedish adolescents.

With its compensatory mandate, the school is essential for health-promoting interventions. There are evaluated programs available that prevent mental problems, mental illnesses and various risk behaviours. However, there is a dearth of evaluated interventions designed to promote mental well-being in adolescents, which are adapted for upper secondary school. It was against this background that the development and evaluation of the Solution-focused Intervention for Mental health (SIM) began in 2018. This presentation will briefly overview the intervention, its components, design and results from feasibility studies. As an intervention programme, SIM consists of group-based coaching that starts from the core components and indicators of mental well-being and enjoying school. Thus, the intervention is based on a normative model of mental well-being; however, the dialogue conducted during the nine two-hour weekly group sessions is based on the solution-focused approach and its techniques. Specially trained teachers facilitating the content and process during group sessions lead SIM. The SIM programme is manual-based and designed to help students discover, explore, practice and develop existing personal resources in order to strengthen hedonic and eudemonic well-being. The teacher uses solution-focused coaching techniques to encourage the students to practise and discover how to utilise their existing resources. By focusing on what works small steps can be taken towards a desired future using indicators of well-being and solution-focused techniques. SIM has so far been tested in feasibility studies in 2019 (n∼140), 2021 (n∼200) and 2023 (n∼50). Results from focus group interviews, session scales ratings and pairwise testing of changes in well-being after compared to before interventions show promising results with increased well-being and total effect sizes ranging from Coheńs d of 0.19 to 0.59. SIM is now ready to be properly evaluated in a randomised controlled trial.

The latest World mental health report states that mental health is an integral component of health and well-being and is more than the absence of pathology. Indeed, the view of mental health is slowly shifting to an emphasis on positive health indicators as national authorities around the world are increasingly adopting the two continua model of mental health (TCM). Adopting the TCM has several important implications for public health practice. One is that the epidemiological surveillance will have to include measures of both mental illness and mental well-being. The purpose of this presentation is to illuminate the conceptual and practical use of the TCM in the analysis of adolescent mental health. The presentation will be limited to a focus on the theoretical underpinnings and methodological considerations made to operationalize and categorize mental health according to the TCM. It will consider the added value of the TCM to epidemiological surveillance as well as its implications for public health practice when it comes to meeting population needs with appropriate interventions. To construct the model, data from population-based regional public health surveys among adolescents including validated measures of both mental ill health and mental well-being was used. The Kessler 6 scale was used to estimate the proportion of adolescents with or without probable serious mental illness (SMI, >13) and the Mental Health Continuum - Short Form was used to estimate the proportion of adolescents with flourishing (FMH), moderate (MMH) or languishing (LMH) mental health according to the original categorization developed by Keyes. Combining these two dimensions of mental health and their respective categories will yield six mental health status groups: Complete mental health = FMH without SMI, Vulnerable = MMH without SMI, Most vulnerable = LMH without SMI, Symptomatic but content = SMI with FMH, Troubled = SMI with MMH, and Most troubled = SMI with LMH.

Viewing mental health from a two continua perspective, this presentation focuses on results of pooled data from a recurrent cross-sectional survey, carried out in ninth and eleventh grade in lower and upper secondary school of Västmanland county, Sweden, 2020 - weeks prior to the Covid-19 outbreak - and 2023. In total, 7908 students participated of which 50% were girls (2020 N = 3880; 2023 N = 4028; response rate≈72%). A compilation of the results according to the two continua model and the six mental health status groups described in the previous presentation shows that 39.0% are categorized as having Complete Mental Health (CMH), 1.6% as Symptomatic But Content (SBC), 36.7% as Vulnerable (V), and 2.9% as being the Most Vulnerable (MV). Further, 12.8% are categorized as being Troubled (T) and 6.9% as Most Troubled (MT). Statistically significant differences are seen between boys and girls in the categories CMH (boys=47.4%, girls=30.8%), SBC (boys 1.0%, girls 2.1%), T (boys 7.2%, girls 18.3%) and MT (boys 3.7%, girls 10.1%). Significant changes over time, between 2020 and 2023, are seen in SBC (0.9% statistically significant increase) and MV (1.9% statistically significant increase). When divided by sex, significant changes over time are only seen among girls: in CMH (5.3% statistically significant decrease), MV (1.9% statistically significant increase) and SBC (1.3% statistically significant increase). No statistically significant changes are seen over time for boys. The result indicates that only four out of ten adolescents have a CMH. The differences between boys and girls are substantial; almost five out of ten boys and three out of ten girls has CMH. This emphasizes the importance of promoting mental well-being, especially among girls. The result also implies the importance of strengthening well-being in the large group without flourishing mental health since the latter can also provide a buffer against mental illness.