There is concern about potential effects of radiofrequency fields generated by mobile phones on cancer risk. Most previous studies have found no association between mobile phone use and acoustic neuroma, although information about long-term use is limited.
We conducted a population-based, nation-wide, case-control study of acoustic neuroma in Sweden. Eligible cases were persons aged 20 to 69 years, who were diagnosed between 2002 and 2007. Controls were randomly selected from the population registry, matched on age, sex, and residential area. Postal questionnaires were completed by 451 cases (83%) and 710 controls (65%).
Ever having used mobile phones regularly (defined as weekly use for at least 6 months) was associated with an odds ratio (OR) of 1.18 (95% confidence interval = 0.88 to 1.59). The association was weaker for the longest induction time (≥10 years) (1.11 [0.76 to 1.61]) and for regular use on the tumor side (0.98 [0.68 to 1.43]). The OR for the highest quartile of cumulative calling time (≥680 hours) was 1.46 (0.98 to 2.17). Restricting analyses to histologically confirmed cases reduced all ORs; the OR for ≥680 hours was 1.14 (0.63 to 2.07). A similar pattern was seen for cordless land-line phones, although with slightly higher ORs. Analyses of the complete history of laterality of mobile phone revealed considerable bias in laterality analyses.
The findings do not support the hypothesis that long-term mobile phone use increases the risk of acoustic neuroma. The study suggests that phone use might increase the likelihood that an acoustic neuroma case is detected and that there could be bias in the laterality analyses performed in previous studies.
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From the aInstitute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden; bDepartment of Clinical Neuroscience, Karolinska Hospital, Stockholm, Sweden; cDepartment of Neurosurgery, Umeå University, Umeå, Sweden; dDepartment of Otorhinolaryngology, Sahlgrenska University Hospital, Göteborg, Sweden; eDepartment of Otorhinolaryngology, Linköping University Hospital, Linköping, Sweden; fDepartment of Neurosurgery, Uppsala University Hospital, Uppsala, Sweden; and gDepartment of Neurosurgery, Skåne University Hospital, Lund, Sweden.
Supported by fund from the Swedish Council for Working Life and Social Research.
M.F. is co-investigator of the COSMOS cohort study, funded by the Swedish Research Council, the Swedish Council for Working Life and Social Research, AFA Insurance, and VINNOVA (The Swedish Governmental Agency for Innovation Systems). VINNOVA received funds for this purpose from TeliaSonera, EricssonAB, and Telenor. The provision of funds to the COSMOS study investigators via VINNOVA is governed by agreements that guarantees COSMOS’ complete scientific independence. M.F. is vice chairman of the International Commission on Non-Ionizing Radiation Protection, an independent body setting guidelines for nonionizing radiation protection. She serves as advisor to a number of national and international public advisory and research steering groups concerning the potential health effects of exposure to nonionizing radiation. The other authors have no conflicts to report.
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Correspondence: Maria Feychting, Karolinska Institutet, Institute of Environmental Medicine, Box 210, 171 77 Stockholm, Sweden. E-mail: firstname.lastname@example.org.