Lonn S, Ahlbom A, Hall P, Feychting M, and the Swedish Interphone study group (2005)
This study was part of the INTERPHONE study, an international case-control study examining cell phones and cancer risk. It was conducted in Sweden from September 2000 to August 2002. Cases of glioma and meningioma were identified continuously from hospital clinics, and cancer registries were also searched for additional cases. The authors identified 499 glioma cases and 320 meningioma cases. Controls were randomly selected from the same geographical areas as the cases, and were stratified on age (5-year groups), gender, and residential area. A total of 956 controls were identified. All cases and controls were approached as soon as possible after identification and asked to participate in a personal interview. Some information was obtained from proxy respondents, some by phone interview (4% cases, 4% controls), and a few by mailed questionnaire. Information was obtained on regular use of a cell phone, quantity and duration of use, and type of phone used. Medical records were examined for information about type, histopathology, site, and laterality of the tumour. In the analysis of a possible association of laterality of phone use and laterality of tumours, left- and right-side tumours were studied separately. The controls were randomly assigned to two separate control groups - one for right-side tumours and one for left-side tumours. If individuals used both hands for phone use they were defined as ipsilateral use. In the statistical analysis, adjustments were made for age, gender, residential area, and education.
Participation rates were 74% (n=371) for glioma cases, 85% (n=273) for meningioma cases, and 71% (n=674) for controls. Reasons for nonparticipation included refusal, illness, and failure to reach the person.
The odds ratio (OR) did not vary between men and women and their results were combined. For regular cell phone use, regardless of duration, the OR was 0.8 (95% CI 0.6, 1.0) for glioma, and 0.7 (0.5, 0.9) for meningioma. The OR did not increase with duration of use. There were no increased ORs for any subcategories of glioma, and there was no association with self-reported laterality of phone use and tumour laterality. The ORs increased among glioma and meningioma cases for ipsilateral cell phone use of at least 10 years duration, but the results were not statistically significant. In addition the corresponding results for contralateral phone use showed a decreased OR, also with wide confidences intervals. This suggests that recall bias may have affected the results. Also, there were no increased ORs for ipsilateral phone use when the analysis was restricted to the temporal or parietal lobes - the areas where the exposure from mobile phones is highest.
The authors conclude that their data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma.