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Maria Feychting

Publications and source records attributed to Maria Feychting.

34 records · Page 2Linked to original sources
PubMed2005

p53 Genotypes and risk of glioma and meningioma.

Brain tumors have previously been associated with the Li-Fraumeni syndrome that often is caused by p53 germ line mutations. Therefore, we investigated if polymorphisms of p53 were associated with an increased risk of meningioma and glioma and integrated the polymorphism analyses with detailed information on family history of cancer. In a population-based case-control study, DNA was extracted from 205 glioma and 164 meningioma cases identified during 2000 to 2002 in Sweden and from 374 controls selected randomly from the general population, stratified on age, sex, and geographic region. The Swedish Cancer Registry confirmed a cancer in family members in 86% of cases and controls that reported a family history of cancer. p53 single nucleotide polymorphism (SNP) analyses were done on three SNPs from the promoter region, codon 72 in exon 4, and intron 6. Overall, no associations were found for any of the SNPs. Analyses of the combinations of the three SNPs were also done. The CC-CG-CC-specific polymorphism combination was associated with an odds ratio (OR) of 1.36 [95% confidence interval (95% CI), 0.68-2.72] for glioma and 1.36 (0.64-2.88) for meningioma. When restricting the analyses to cases and controls with a positive family history of cancer, the corresponding results were OR of 3.62 (95% CI, 1.05-12.48) for glioma and 5.69 (1.81-17.96) for meningioma. This study is novel in suggesting an increased risk of brain tumors when the analysis is restricted to those with a history of cancer in the family. However, we cannot rule out the possibility that these results are due to chance.

Brain Neoplasms↗
PubMed2004

Allergic conditions and risk of hematological malignancies in adults: a cohort study.

BACKGROUND: Two contradictory hypotheses have been proposed to explain the relationship between allergic conditions and malignancies, the immune surveillance hypothesis and the antigenic stimulation hypothesis. The former advocates that allergic conditions may be protective against development of cancer, whereas the latter proposes an increased risk. This relationship has been studied in several case-control studies, but only in a few cohort studies. METHODS: The association between allergic conditions and risk of developing leukemia, Hodgkin's disease, non-Hodgkin's lymphoma and myeloma was investigated in a cohort of 16,539 Swedish twins born 1886-1925. Prospectively collected, self-reported information about allergic conditions such as asthma, hay fever or eczema was obtained through questionnaires administered in 1967. The cohort was followed 1969-99 and cancer incidence was ascertained from the Swedish Cancer Registry. RESULTS: Hives and asthma tended to increase the risk of leukemia (relative risk [RR] = 2.1, 95% Confidence Interval [CI] 1.0-4.5 and RR = 1.6, 95% CI 0.8-3.5, respectively). There was also an indication of an increased risk of non-Hodgkin's lymphoma associated with eczema during childhood (RR = 2.3, 95% CI 1.0-5.3). CONCLUSION: In contrast to most previous studies, our results do not indicate a protective effect of allergic conditions on the risk of developing hematological malignancies. Rather, they suggest that allergic conditions might increase the risk of some hematological malignancies.

Adult↗
PubMed2004

Incidence trends of adult primary intracerebral tumors in four Nordic countries.

Brain tumors are some of the most lethal adult cancers and there is a concern that the incidence is increasing. It has been suggested that the reported increased incidence can be explained by improvements in diagnostic procedures, although this has not been totally resolved. The aim of our study was to describe the incidence trends of adult primary intracerebral tumors in four Nordic countries during a period with introduction of new diagnostic procedures and increasing prevalence of mobile phone users. Information about benign and malignant primary intracerebral tumor cases 20-79 years of age was obtained from the national cancer registries in Denmark, Finland, Norway and Sweden for the years 1969-98 and estimates of person-years at risk were calculated from the information obtained from national population registries. Annual age standardized incidence rates per 100,000 person-years were calculated and time trends analyses were carried out using Poisson regression. The overall incidence of all intracerebral tumors ranged from 8.4-11.8 for men and 5.8-9.3 for women, corresponding to an average annual increase of 0.6% for men (95% confidence interval [CI] = 0.4, 0.7) and 0.9% for women (95% CI = 0.7, 1.0). The increase in the incidence was confined to the late 1970s and early 1980s and coinciding with introduction of improved diagnostic methods. This increase was largely confined to the oldest age group. After 1983 and during the period with increasing prevalence of mobile phone users, the incidence has remained relatively stable for both men and women.

Adult↗
PubMed2004

Occupational magnetic field exposure and myocardial infarction incidence.

BACKGROUND: Studies on healthy volunteers have seen reduced heart rate variability after exposure to extremely low-frequency electric and magnetic fields (EMF). Because reduced heart rate variability has been linked to cardiovascular disease risk, it has been hypothesized that exposure to EMF might increase the risk of cardiovascular disease. One epidemiologic study has shown increased mortality from cardiovascular conditions in utility workers with elevated exposure to magnetic fields, but several other epidemiologic studies have failed to confirm this result. We tested the hypothesis that occupational EMF exposure increases the risk of myocardial infarction in a large population-based case-control study of myocardial infarction, with detailed information on potential confounders. METHODS: We used data from the SHEEP study, which is a population-based case-control study of acute myocardial infarction in Stockholm. Occupational EMF exposure was based on job titles 1, 5, and 10 years before diagnosis. We used 2 approaches to classify exposure: first, specific individual job titles with presumed elevated EMF exposure, and second, classification of subjects according to a job-exposure matrix. RESULTS: We found no increased risk of myocardial infarction in subjects classified as having elevated EMF exposure. For the highest exposure category of > or = 0.3 microT according to the job-exposure matrix, the adjusted relative risk was = 0.57 (95% confidence interval = 0.36-0.89). CONCLUSIONS: The results of this study do not support the hypothesis that occupational EMF exposure increases the risk of myocardial infarction.

Acute Disease↗
PubMed2004

Mobile phone use and the risk of acoustic neuroma.

BACKGROUND: Radiofrequency exposure from mobile phones is concentrated to the tissue closest to the handset, which includes the auditory nerve. If this type of exposure increases tumor risk, acoustic neuroma would be a potential concern. METHODS: In this population-based case-control study we identified all cases age 20 to 69 years diagnosed with acoustic neuroma during 1999 to 2002 in certain parts of Sweden. Controls were randomly selected from the study base, stratified on age, sex, and residential area. Detailed information about mobile phone use and other environmental exposures was collected from 148 (93%) cases and 604 (72%) controls. RESULTS: The overall odds ratio for acoustic neuroma associated with regular mobile phone use was 1.0 (95% confidence interval = 0.6-1.5). Ten years after the start of mobile phone use the estimates relative risk increased to 1.9 (0.9-4.1); when restricting to tumors on the same side of the head as the phone was normally used, the relative risk was 3.9 (1.6-9.5). CONCLUSIONS: Our findings do not indicate an increased risk of acoustic neuroma related to short-term mobile phone use after a short latency period. However, our data suggest an increased risk of acoustic neuroma associated with mobile phone use of at least 10 years' duration.

Acoustic Stimulation↗
PubMed2003

Obesity and hormone-dependent tumors: cohort and co-twin control studies based on the Swedish Twin Registry.

Obesity increases the risk of certain cancer types, e.g., cancer of the endometrium, colon and gallbladder. For some other cancer forms, e.g., prostate cancer, the association is less clear. We examined the association between body mass index (BMI) and hormone-dependent tumors, utilizing a cohort of 21,884 Swedish twins born during 1886-1925. Information about BMI at different ages and potential confounding factors was collected prospectively. The Swedish Cancer Registry was used to identify cases of cancer in the prostate (n = 666), breast (n = 607), corpus uteri (n = 150) and ovary (n = 118) during 1969-1997. The material was analyzed as a traditional cohort and with co-twin control analyses that allow for control of genetic influences. Obesity (BMI >/=30 kg/m(2)) at baseline was positively associated with cancer in the corpus uteri [relative risk (RR) = 3.03, 95% confidence interval (CI) 1.82-5.03], as was BMI at age 25, independently of BMI at baseline. Increased risk was also found for breast cancer but only in older women (>/=70 years). Overweight at age 25 was associated with decreased risk of breast cancer (RR = 0.51, 95% CI 0.33-0.78). No association was found for prostate cancer. We conclude that age is an important effect modifier of cancer risk associated with obesity and that obesity and overweight in young adult life may affect cancer risk also later in life.

Adult↗
PubMed2003

Cohort studies of association between self-reported allergic conditions, immune-related diagnoses and glioma and meningioma risk.

An inverse association between self-reported allergies and glioma and meningioma risk, has been previously observed in case-control studies. Approximately 27% (median) of the information on both glioma and meningioma in these studies, however, is collected from proxy respondents. In fact, the odds ratios (OR) among previous brain tumor studies are inversely related to the proportion of proxy respondents (Pearson correlation coefficient = -0.94; 95% CI = -1.00 to -0.65); this correlation suggests bias. We therefore constructed 3 cohorts based on the Swedish Twin, Hospital Discharge, and Cancer Registries. In Cohorts I (14,535 people developed 37 gliomas and 41 meningiomas) and II (29,573 people developed 42 gliomas and 26 meningiomas) median time from self-report of allergies to brain tumor diagnosis was 15.4 years. Cohort III, which overlaps with Cohorts I and II (52,067 people developed 68 gliomas and 63 meningiomas), was linked to the Swedish Hospital Discharge Registry where pre-brain tumor immune-related discharge diagnoses were recorded. Allergies are inversely associated with glioma risk in Cohort I (Hazard ratio [HR] = 0.45; 95% CI = 0.19-1.07) and among high grade (III and IV, HR = 0.45; 95% CI = 0.11-1.92) but not low grade (I and II, HR = 2.60; 95% CI = 0.86-7.81) gliomas in Cohort II. In Cohort III, immune-related discharge diagnoses are also inversely associated with glioma (HR = 0.46; 95% CI = 0.14-1.49). There is no strong evidence against (and some for) the hypothesis that allergies reduce glioma risk.

Adult↗
PubMed2003

Electromagnetic radiation.

Electromagnetic fields (EMF) are ubiquitous in modern society. It is well known that exposure to strong fields can result in acute effects, such as burns; the mechanisms behind such effects are well established. There is, however, also a concern that long-term exposure to weak fields might have health effects due to an as-yet unknown mechanism. Because of the already widespread exposure, even small health effects could have profound public health implications. Comprehensive research efforts are therefore warranted, and are indeed ongoing. The strongest evidence for health risks is from exposure to fields generated in connection with use of electric power. As for fields used by telecommunications technology, there is still considerably fewer data available and for the time being there is only very weak support for the existence of health effects. However, extensive research activities are ongoing and much more data will be available in the near future. This situation of scientific uncertainty and considerable public concern creates dilemmas for decision makers.

Electromagnetic Fields↗
PubMed2003

Occupational magnetic field exposure and neurodegenerative disease.

BACKGROUND: Several studies have identified occupational exposure to extremely low-frequency electromagnetic fields (EMF) as a potential risk factor for neurodegenerative disease, but the evidence is contradictory and inconclusive. METHODS: We conducted a cohort study to explore these associations. We studied all economically active individuals in the Swedish 1980 census (4,812,646 subjects), and followed them for neurodegenerative disease mortality from 1981 through 1995. Information about occupation was available for 1970 and 1980. A job-exposure matrix based on magnetic field measurements was used to assess EMF exposure. RESULTS: An increased risk of Alzheimer's disease mortality was observed among men exposed both in 1970 and 1980 (relative risk = 2.3; 95% confidence interval = 1.6-3.3 for exposure >/=0.5 microT). The associations were most pronounced for early-onset Alzheimer's disease mortality or with follow-up limited to 10 years after the last known occupation. Amyotrophic lateral sclerosis was not associated with EMF exposure, but the risk estimate with "electrical and electronics work" was 1.4 (95% confidence interval = 1.1-1.9). CONCLUSIONS: Our study gives some support to the hypothesis that EMF exposure increases the risk of early-onset Alzheimer's disease, and suggests that magnetic field exposure may represent a late-acting influence in the disease process. Electric shock is an unlikely explanation for the increased risk of amyotrophic lateral sclerosis in "electrical and electronics work" in this study.

Adolescent↗
PubMed2002

Risk of severe cardiac arrhythmia in male utility workers: a nationwide danish cohort study.

To address concern about the potential cardiovascular effects of occupational exposure to electromagnetic fields in the 50- to 60-Hz frequency band, the authors launched an epidemiologic study of the incidence of severe cardiac arrhythmia, as indicated by the need for a pacemaker, in a nationwide cohort of Danish utility workers. The cohort of 24,056 men employed at utility companies between 1900 and 1993 was linked to the nationwide, population-based Danish Pacemaker Register, and the numbers of persons who had undergone pacemaker implantation between 1982 and 2000 were compared with corresponding numbers in the general population. In addition, the data on the utility workers were fitted to a multiplicative Poisson regression model in relation to estimated levels of exposure to 50-Hz electromagnetic fields. Overall, based on 135 men with pacemakers (140 expected), there was no increased risk of severe cardiac arrhythmia among the utility employees; the risk estimate was 0.96 (95% confidence interval: 0.81, 1.14). No clear dose-response pattern emerged with increasing levels of exposure to electromagnetic fields or with duration of employment. These results are largely reassuring, since they do not support the hypothesis of a link between occupational exposure to electromagnetic fields and an excess risk of severe cardiovascular arrhythmia leading to permanent implantation of a pacemaker.

Adolescent↗
PubMed2002

Relative contribution of residential and occupational magnetic field exposure over twenty-four hours among people living close to and far from a power line.

This study sought to estimate the relative contribution of exposure to 50 Hz magnetic fields experienced at home, at work/school, or elsewhere to the total exposure over 24 hr. Personal exposure meters were carried by 97 adults and children in the Stockholm area. About half of the subjects lived close (<50 m) to a transmission line and half far (>100 m) away. Spot measurements and calculations for the residential exposure were also made. For subjects living<50 m from the line, the exposure at home contributed about 80% of the total magnetic field exposure, measured in mT-hours. Adults living far away experienced only 38% of the total exposure at home, but children still received 55%. Subjects with low time-weighted average (TWA) exposure both at home and at work spent 84% of their time in fields <0.1 microT, and those with high TWA at both locations spent 69% of their time in fields > or = 0.2 microT. This contrast was diluted if only exposure at one location was considered. For spot measurements and calculations of the residential exposure, both sensitivity and specificity was good. However, the intermediate field exposure category (0.1-0.19 microT) showed poor correlation to the 24 hr personal measurements.

Adolescent↗
PubMed2002

Childhood leukemia and magnetic fields in infant incubators.

In studies of magnetic field exposure and childhood leukemia, power lines and other electrical installations close to the children's homes constitute the most extensively studied source of exposure. We conducted a study to assess whether exposure to magnetic fields in infant incubators is associated with an increased leukemia risk. We identified all children with leukemia born in Sweden between 1973 and 1989 from the national Cancer Registry and selected at random one control per case, individually matched by sex and time of birth, from the study base. We retrieved information about treatment in infant incubators from medical records. We made measurements of the magnetic fields inside the incubators for each incubator model kept by the hospitals. Exposure assessment was based on measurements of the magnetic field level inside the incubator, as well as on the length of treatment. For acute lymphoblastic leukemia, the risk estimates were close to unity for all exposure definitions. For acute myeloid leukemia, we found a slightly elevated risk, but with wide confidence intervals and with no indication of dose response. Overall, our results give little evidence that exposure to magnetic fields inside infant incubators is associated with an increased risk of childhood leukemia.

Adolescent↗
PubMedDate not supplied

Health effects of static magnetic fields--a review of the epidemiological evidence.

Potential health effects of static magnetic fields have received far less attention than, for example, power frequency or radiofrequency fields. Static fields are found in certain occupational settings, e.g. in the aluminium and chloralkali industries, in arc-welding processes, and certain railways systems. Magnetic resonance imaging (MRI) for medical diagnosis is another source. This paper summarizes the epidemiological evidence of static magnetic field exposure and long-term health effects. There are only a few epidemiological studies available, and the majority of these have focused on cancer risks. There are some reports on reproductive outcomes, and sporadic studies of other outcomes. Overall, few occupational studies have focused specifically on effects of static magnetic field exposure, and exposure assessment have consequently been poor or non-existent. Results from studies that have estimated static magnetic field exposure have not indicated any increased cancer risks, but they are generally based on small numbers of cases and crude exposure assessment. Control of confounding has been limited, and it is likely that the "healthy worker" effect have influenced the results. A few studies have reported results on reproductive outcomes among aluminium workers and MRI operators, but limitations in study designs prevent conclusions. A problem in epidemiological studies of static magnetic fields is that workers in exposed occupations are also exposed to a wide variety of other potentially harmful agents, including some known carcinogens. In conclusion, the available evidence from epidemiological studies is not sufficient to draw any conclusions about potential health effects of static magnetic field exposure.

Fertility↗