Wireless phone use in childhood and adolescence and neuroepithelial brain tumours: Results from the international MOBI-Kids study

In recent decades, the possibility that use of mobile communicating devices, particularly wireless (mobile and cordless) phones, may increase brain tumour risk, has been a concern, particularly given the considerable increase in their use by young people. MOBI-Kids, a 14-country (Australia, Austria, Canada, France, Germany, Greece, India, Israel, Italy, Japan, Korea, the Netherlands, New Zealand, Spain) case-control study, was conducted to evaluate whether wireless phone use (and particularly resulting exposure to radiofrequency (RF) and extremely low frequency (ELF) electromagnetic fields (EMF)) increases risk of brain tumours in young people. Between 2010 and 2015, the study recruited 899 people with brain tumours aged 10 to 24 years old and 1,910 controls (operated for appendicitis) matched to the cases on date of diagnosis, study region and age. Participation rates were 72% for cases and 54% for controls. The mean ages of cases and controls were 16.5 and 16.6 years, respectively; 57% were males. The vast majority of study participants were wireless phones users, even in the youngest age group, and the study included substantial numbers of long-term (over 10 years) users: 22% overall, 51% in the 20-24-year-olds. Most tumours were of the neuroepithelial type (NBT; n = 671), mainly glioma. The odds ratios (OR) of NBT appeared to decrease with increasing time since start of use of wireless phones, cumulative number of calls and cumulative call time, particularly in the 15-19 years old age group. A decreasing trend in ORs was also observed with increasing estimated cumulative RF specific energy and ELF induced current density at the location of the tumour. Further analyses suggest that the large number of ORs below 1 in this study is unlikely to represent an unknown causal preventive effect of mobile phone exposure: they can be at least partially explained by differential recall by proxies and prodromal symptoms affecting phone use before diagnosis of the cases. We cannot rule out, however, residual confounding from sources we did not measure. Overall, our study provides no evidence of a causal association between wireless phone use and brain tumours in young people. However, the sources of bias summarised above prevent us from ruling out a small increased risk.

Maternal fetal loss history and increased acute leukemia subtype risk in subsequent offspring: a systematic review and meta-analysis

PURPOSE

History of fetal loss including miscarriage and stillbirth has been inconsistently associated with childhood (0-14 years) leukemia in subsequent offspring. A quantitative synthesis of the inconclusive literature by leukemia subtype was therefore conducted.

METHODS

Eligible studies (N = 32) were identified through the screening of over 3500 publications. Random-effects meta-analyses were conducted on the association of miscarriage/stillbirth history with overall (AL; 18,868 cases/35,685 controls), acute lymphoblastic (ALL; 16,150 cases/38,655 controls), and myeloid (AML; 3042 cases/32,997 controls) leukemia. Sensitivity and subgroup analyses by age and ALL subtype, as well as meta-regression were undertaken.

RESULTS

Fetal loss history was associated with increased AL risk [Odds Ratio (OR) 1.10, 95% Confidence Intervals (CI) 1.04-1.18]. The positive association was seen for ALL (OR 1.12, 95%CI 1.05-1.19) and for AML (OR 1.13, 95%CI 0.91-1.41); for the latter the OR increased in sensitivity analyses. Notably, stillbirth history was significantly linked to ALL risk (OR 1.33, 95%CI 1.02-1.74), but not AML. By contrast, the association of ALL and AML with previous miscarriage reached marginal significance. The association of miscarriage history was strongest in infant ALL (OR 2.34, 95%CI 1.19-4.60).

CONCLUSIONS

In this meta-analysis involving >50,000 children, we found noteworthy associations by indices of fetal loss, age at diagnosis, and leukemia type; namely, of stillbirth with ALL and miscarriage history with infant ALL. Elucidation of plausible underlying mechanisms may provide insight into leukemia pathogenesis and indicate monitoring interventions prior to and during pregnancy.

Maternal screening for early postnatal vulnerability

Research has highlighted the wide impact of maternal mental health problems during and beyond the postpartum period and the public health role of community health professionals in early detection of women who may be at risk. This paper aims to describe, explore and test an a priori hypothesised conceptual model of postnatal experience, identifying the relationships between postnatal mental vulnerability and postnatal adjustment to maternal roles and attitudes, marital/partner-relationship and sense of coherence. Three validated self-report questionnaires (WAST, MAMA, SOC) measuring the variables of the encompassing framework and EPDS were administered in random order. The conceptual models were tested using the software IBM SPSS Statistics and LISREL and the tests performed were: Student's ttest, chi-square tests, Explanatory factor analysis using a Varimax rotation Principal Components Method, Confirmatory analysis -known as structural equation modelling- of principal components. Psychometric scores indicate high correlation between WAST, MAMA, SOC and EPDS. An exploratory factor analysis confirmed the role of SOC, specific MAMA subscales (maternal roles and attitudes, body image, sex, breasts, nausea) and WAST (relationship tension and emotional and physical abuse) subscales (KMO measure of sampling adequacy=0.735 and Bartlett's test of sphericity=184,786, df=36, p<0.0005). The latent variables confirmed with SEM were marital relationship, maternity experience and self-efficacy (Chi-square=28.45, df=24, P-value=0.24, RMSEA=0.046 p<0.05). Marital Relationship (Factor I: Eigenvalue=3.066) concerning lack of or disappointment with partner support, poor marital relationship and emotional/physical abuse has been associated with high levels of postpartum anxiety and depression. Maternity Experience (Factor II: Eigenvalue=1.280) representing postnatal roles and attitudes towards their infant can be as useful as mood changes for evaluation of mothers. Self-Efficacy (Factor III: Eigen- value=3.144) and especially attitudes regarding body image, sex and coping resources and options of dealing with the stressor, has been demonstrated that serve as a mediator or buffer for psychological distress. The results of this study have implications for the prevention and intervention of postnatal adjustment difficulties both of which need to be intensified in order to minimise perinatal mental vulnerability.

History of Maternal Fetal Loss and Childhood Leukaemia Risk in Subsequent Offspring: Differentials by Miscarriage or Stillbirth History and Disease Subtype

BACKGROUND

Despite the putative intrauterine origins of childhood (0-14 years) leukaemia, it is complex to assess the impact of perinatal factors on disease onset. Results on the association of maternal history of fetal loss (miscarriage/stillbirth) with specific disease subtypes in the subsequent offspring are in conflict. We sought to investigate whether miscarriage and stillbirth may have different impacts on the risk of acute lymphoblastic leukaemia (ALL) and of its main immunophenotypes (B-cell and T-cell ALL), as contrasted to acute myeloid leukaemia (AML).

METHODS

One thousand ninety-nine ALL incidents (957 B-ALL) and 131 AML cases along with 1:1 age and gender-matched controls derived from the Nationwide Registry for Childhood Hematological Malignancies and Brain Tumors (1996-2013) were studied. Multivariable regression models were used to assess the roles of previous miscarriage(s) and stillbirth(s) on ALL (overall, B-, T-ALL) and AML, controlling for potential confounders.

RESULTS

Statistically significant exposure and disease subtype-specific associations of previous miscarriage(s) exclusively with AML [odds ratio (OR) 1.67, 95% confidence interval (CI) 1.00, 2.81] and stillbirth(s) with ALL [OR 4.82, 95% CI 1.63, 14.24] and B-ALL particularly, emerged.

CONCLUSION

Differential pathophysiological pathways pertaining to genetic polymorphisms or cytogenetic aberrations are likely to create hostile environments leading either to fetal loss or the development of specific leukaemia subtypes in subsequent offspring, notably distinct associations of maternal miscarriage history confined to AML and stillbirth history confined to ALL (specifically B-ALL). If confirmed and further supported by studies revealing underlying mechanisms, these results may shed light on the divergent leukemogenesis processes.

Socioeconomic disparities in survival from childhood leukemia in the United States and globally: a meta-analysis

BACKGROUND

Despite advancements in the treatment of childhood leukemia, socioeconomic status (SES) may potentially affect disease prognosis. This study aims to evaluate whether SES is associated with survival from childhood leukemia.

METHODS

The US National Cancer Institute Surveillance, Epidemiology and End Results Program (SEER) 1973-2010 data were analyzed; thereafter, results were meta-analyzed along with those from survival (cohort) studies examining the association between SES indices and survival from childhood leukemia (end-of-search date: 31 March 2014). Random-effects models were used to calculate pooled effect estimates (relative risks, RRs); meta-regression was also used.

RESULTS

We included 29 studies yielding 28 804 acute lymphoblastic leukemia (ALL), 3208 acute myeloblastic leukemia (AML) and 27 650 'any' leukemia (denoting joint reporting of all subtypes) cases. According to individual-level composite SES indices, children from low SES suffered from nearly twofold higher death rates from ALL (pooled RR: 1.83, 95% confidence interval 1.00-3.34, based on four study arms); likewise, death RRs derived from an array of lower area-level SES indices ranged between 1.17 and 1.33 (based on 11 study arms). Importantly, the survival gap between higher and lower SES seemed wider in the United States, with considerably (by 20%-82%) increased RRs for death from ALL in lower SES. Regarding AML, poorer survival was evident only when area-level SES indices were used. Lastly, remoteness indices were not associated with survival from childhood leukemia.

CONCLUSION

Children with lower SES suffering childhood leukemia do not seem to equally enjoy the impressive recent survival gains. Special health policy strategies and increased awareness of health providers might minimize the effects of socioeconomic disparities.

Is birth weight associated with childhood lymphoma? A meta-analysis

Several risk factors have been identified for childhood lymphomas. The purpose of this meta-analysis was to synthesize current evidence regarding the association between birth weight with primarily the risk for non-Hodgkin lymphoma (NHL), given its similarity to acute lymphoblastic leukemia, Hodgkin lymphoma (HL) and any category of lymphoma. Two cohort (278,751 children) and seven case-control studies (2,660 cases and 69,274 controls) were included. Effects estimates regarding NHL, HL and any lymphoma were appropriately pooled using fixed or random effects model in two separate analyses: specifically, high was compared to normal or any birth weight. Similarly, low was compared to normal or any birth weight. No statistically significant association was found between high birth weight, as compared to normal birth weight, and risk for NHL plus Burkitt lymphoma (OR = 1.17, 95% CI = 0.76-1.80, random effects), HL (OR = 0.94, 95% CI = 0.64-1.38, fixed effects) or any plus Burkitt lymphoma (OR = 1.09, 95% CI = 0.76-1.56, fixed effects). A null association emerged when low was compared with normal birth weight for NHL plus Burkitt lymphoma (OR = 1.07, 95% CI = 0.71-1.62, random effects), HL (OR = 0.94, 95% CI = 0.54-1.65, fixed effects) or any plus Burkitt lymphoma (OR = 1.02, 95% CI = 0.79-1.33, fixed effects). Accordingly, no association was found when high or low birth weight was compared to any birth weight. Although current evidence suggests no association, birth weight might be a too crude indicator to reveal a genuine association of fetal growth with specific lymphoma categories; hence, there is an emerging need for use of more elaborate proxies, at least those accounting for gestational week.

Maternal smoking during pregnancy and childhood lymphoma: a meta-analysis

Results from epidemiological studies exploring the association between childhood lymphoma and maternal smoking during pregnancy have been contradictory. This meta-analysis included all published cohort (n = 2) and case-control (n = 10) articles; among the latter, the data of the Greek Nationwide Registry for Childhood Hematological Malignancies study were updated to include all recently available cases (-2008). Odds ratios (ORs), relative risks and hazard ratios were appropriately pooled in three separate analyses concerning non-Hodgkin lymphoma (NHL, n = 1,072 cases), Hodgkin lymphoma (HL, n = 538 cases) and any lymphoma (n = 1,591 cases), according to data availability in the included studies. An additional metaregression analysis was conducted to explore dose-response relationships. A statistically significant association between maternal smoking (any vs. no) during pregnancy and risk for childhood NHL was observed (OR = 1.22, 95% confidence interval, CI: 1.03-1.45, fixed effects model), whereas the risk for childhood HL was not statistically significant (OR = 0.90, 95% CI: 0.66-1.21, fixed effects model). The analysis on any lymphoma did not reach statistical significance (OR = 1.10, 95% CI = 0.96-1.27, fixed effects model), possibly because of the case-mix of NHL to HL. No dose-response association was revealed in the metaregression analysis. In conclusion, this meta-analysis points to a modest increase in the risk for childhood NHL, but not HL, among children born by mothers smoking during pregnancy. Further investigation of dose-response phenomena in the NHL association, however, warrants accumulation of additional data.

Childhood leukaemias and lymphomas in Greece (1996-2006): a nationwide registration study

BACKGROUND

Monitoring time trends in the incidence of childhood leukaemias and lymphomas requires efficient and continuous data collecting systems. In countries without official cancer registries, such as Greece, ad hoc nationwide registration of incident childhood leukaemias and lymphomas could help elucidate the underlying aetiology and monitor socioeconomic differentials in health care delivery.

METHODS

We registered all cases and produced age, gender, type and immunophenotype specific figures and overall crude and age adjusted annual incidence rates and secular trends for 863 leukaemia and 311 lymphoma incident cases diagnosed in children <15 years of age across Greece during 1996-2006, namely the first 11 years of the Nationwide Registry for Childhood Hematological Malignancies.

RESULTS

The epidemiological profiles of leukaemias/lymphomas in Greece are similar to those in industrialised countries. No secular trends are observed for either malignancy during the studied period. However, the calculated incidence for leukaemia (46.60 cases per 1 million children annually) is among the highest in the EU-27 (19% higher than average; p<0.001), whereas that for lymphoma (16.8 cases per 1 million children annually) is around the EU-27 average.

CONCLUSIONS

Minimal secular changes in childhood leukaemias/lymphomas have been noted recently in the EU-27, which cannot be easily explained in countries with small populations. Therefore, centralised EU databases such as the Automated Childhood Cancer Information System (ACCIS) should be enlarged to generate sufficient statistical power for monitoring time trends. It would be interesting to explore whether different lifestyle patterns across the EU might be responsible for the observed excess leukaemia incidence in countries such as Greece.

Seroprevalence and risk factors for hepatitis A, B, and C among Roma and non-Roma children in a deprived area of Athens, Greece

The prevalence and risk factors of hepatitis A, B, and C (HAV, HBV, and HCV) markers were compared in non-Roma and Roma children who lived in a deprived suburb of Athens, Greece. The study included 216 children, 118 Roma and 98 non-Roma of 9 years median age (range 5-15 years). Among Roma children 98.3% had detectable antibodies to HAV, compared with 32.7% among non-Romas (P < 0.0001). Regarding HBV, 22% Roma children were identified with evidence of past infection (anti-HBc(+)), among whom five (4% of the total) were chronic carriers (HBsAg(+)), whereas no past infection was detected among the non-Romas (P < 0.0001). Markers of past HBV vaccination (anti-HBs(+), anti-HBc(-)) were detected in only 14% Roma but 96% non-Roma children (P-value < 0.0001). There was some indication for intrafamilial transmission of HAV and HBV in Roma school children. Unfavorable living conditions, frequent residency change, lack of child insurance and primary healthcare delivery were significantly associated with seroprevalence of HBV infection among Romas. No child in either group was found positive for HCV markers. These findings document high socioeconomic differentials with regards to preventable communicable diseases, such as HAV and HBV and underline the need for enhancing health policy action targeting pockets of minority childhood populations. Whereas, uptake of HBV vaccination is rather optimal in this general population, the high seroprevalence of HAV among Romas, also calls for implementing general vaccination for HAV, early in life.

Melanoma risk in association with serum leptin levels and lifestyle parameters: a case-control study

BACKGROUND

Solar radiation has been identified as a principal factor for the causation of melanoma, whereas changing lifestyle patterns associated with obesity and diabetes might also contribute to the increasing incidence of the malignancy. No study has investigated the role of leptin, a hormone whose levels increase in obesity and which has also been related to cancer.

PATIENTS AND METHODS

Fifty-five patients with incident melanomas and 165 age- and gender-matched healthy controls were interviewed on the basis of a questionnaire that covers phenotypic features, sociodemographic and medical history variables, lifestyle habits and frequency of consumption of major food groups. Anthropometrical measures were also recorded and blood samples were obtained for determination of serum leptin levels. Adjusted odds ratios (ORs) for melanoma risk were derived through multiple logistic regression analyses.

RESULTS

An excess melanoma risk was observed for sun sensitive individuals and those with high circulating levels of leptin (OR: 1.56, 95% confidence interval 1.07-2.28, P = 0.02), after controlling for obesity indices, diabetes mellitus and education. Increased physical exercise, lower alcohol consumption and plant food consumption seem to play a protective role against melanoma development.

CONCLUSIONS

Melanoma risk was found to be positively associated with serum leptin levels and inversely with healthy lifestyle factors. The findings need to be confirmed in prospective studies.

Circulating adiponectin levels in relation to melanoma: A case–control study

AIM

Melanoma, a malignancy with steadily increasing prevalence, has been associated not only with sun exposure but also with phenotypic characteristics including obesity. Adiponectin, an adipocyte secreted endogenous insulin sensitizer, has been found to play a protective role in several obesity related cancers but has not yet been studied in relation to melanoma. We investigated the association of circulating adiponectin levels with melanoma in Greece, a country with rather low incidence of the disease and high annual sunshine levels.

METHODS

In the context of a case-control study, we studied over a 22-month period 55 patients with incident, histologically confirmed melanoma cases and 165 healthy controls matched for gender and age.

RESULTS

After controlling for the possible confounding effect of education, body mass index and waist-to-hip ratio in multiple logistic regression analyses, sun sensitive skin type was significantly and positively associated with melanoma risk (OR: 2.48, 95% Confidence Interval: 1.22-5.10, p: 0.01). On the contrary, there was a sizeable, though non-significant, inverse association of serum adiponectin levels with the disease (OR: 0.75, 95% Confidence Interval: 0.52-1.10, p: 0.14).

CONCLUSION

A protective role of adiponectin in the development of melanoma cannot be excluded given the presented empirical evidence (25% reduction per one SD of adiponectin) and the direct anti-neoplastic features of the hormone. The results are intriguing enough to point to the need for further investigation.

Breast cancer risk in relation to most prevalent IgE specific antibodies: a case control study in Greece

BACKGROUND

This study aims to explore the debatable role of allergy in breast cancer (BC) by using country-specific biological markers, namely levels of the most prevalent allergen-specific immunoglobulin E in Greece.

PATIENTS AND METHODS

Blood samples and clinical information were collected over a 30-month period from 103 women with histologically-confirmed BC and 103 controls from two university hospitals in Athens. Allergen-specific IgE, against the 12 prevailing allergens in Greece were determined; thereafter, a score comprising the sum of the individual values for this battery of serological IgE determinations was created. Bivariate and multiple logistic regression analyses were undertaken using case-control status as the outcome and IgE-scores as the predictor variable, controlling for socio-demographic, gynecological and lifestyle confounders.

RESULTS

The serum IgE score seemed to be positively related to BC (OR: approximately 1.73; CI: 0.95-3.14; p-value: 0.07). A positive correlation between serological evidence and allergic history among controls was also found (p-value: 0.06).

CONCLUSION

This investigation suggests an IgE-mediated allergic response among women with BC in comparison to their controls. The finding needs confirmation by immuno-epidemiological investigation to clarify the directionality of this association and whether laboratory-ascertained atopy can be considered as a risk-marker of susceptibility in the development of BC.

Intentional injury mortality in the European Union: how many more lives could be saved?

OBJECTIVE

To explore the scope for reducing the number of intentional injury deaths, hypothesizing that all European Union (EU) countries are able to match the experience of the country with the lowest mortality rate for intentional injuries.

DESIGN

Intentional injury mortality data for the three last available years and denominator population estimates were obtained from the World Health Organisation mortality database for the 22 EU countries with more than one million population. To estimate the potential saving of lives, the yearly average age adjusted injury mortality rates were calculated. This issue done for children (0-14), adults (15-64), and elderly people (65 and over), both including and excluding deaths from undetermined cause.

MAIN OUTCOME MEASURES

Number of lives that might potentially be saved if all EU member states matched the lowest intentional injury rate reported by an EU member state.

RESULTS

Over 73% of all intentional injury deaths could have been avoided if all EU countries matched the country with the lowest intentional injury mortality rate. EU member states would have suffered about 600 fewer intentional injury deaths in children, about 40 000 fewer adult deaths, and over 14 000 fewer intentional injury deaths in the elderly. This amounts to over 55 000 lives in a single year.

CONCLUSIONS

Many lives lost through injury might be saved if all countries were to achieve the lowest intentional injury mortality rates reported in the EU. How this theoretical observation might be translated into practice needs to be further explored as the international variation in intentional injury mortality rates in the EU results from a range of factors.