Mobile phone use and risk of acoustic neuroma: results of the Interphone case–control study in five North European countries

Abstract

There is public concern that use of mobile phones could increase the risk of brain tumours. If such an effect exists, acoustic neuroma would be of particular concern because of the proximity of the acoustic nerve to the handset. We conducted, to a shared protocol, six population-based case -control studies in four Nordic countries and the UK to assess the risk of acoustic neuroma in relation to mobile phone use. Data were collected by personal interview from 678 cases of acoustic neuroma and 3553 controls. The risk of acoustic neuroma in relation to regular mobile phone use in the pooled data set was not raised (odds ratio (OR) ¼ 0.9, 95% confidence interval (CI): 0.7 -1.1). There was no association of risk with duration of use, lifetime cumulative hours of use or number of calls, for phone use overall or for analogue or digital phones separately. Risk of a tumour on the same side of the head as reported phone use was raised for use for 10 years or longer (OR ¼ 1.8, 95% CI: 1.1 -3.1). The study suggests that there is no substantial risk of acoustic neuroma in the first decade after starting mobile phone use. However, an increase in risk after longer term use or after a longer lag period could not be ruled out.

Mobile Phones and Head Tumours: A Critical Analysis of Case-Control Epidemiological Studies

“…significant time use, continuity of use or latency of at least 10 years, and ipsilateral tumour detection -showed a rise often s.s. > 100% of malignant brain tumour risk [5,22,24,32] -the same being observed for acoustic neuromas [6,29,31] and parotid gland tumours [16,26] (Table 2).…”

“…• the Interphone protocol considers cordless phone users as not exposed, while it is documented that the rf radiation emitted by cordless can even exceed the intensity of a cell phone [34], so much so that Hardell documents s.s. increases in the risk of meningiomas and acoustic nerve neuromas also in people using only cordless [1][2][3][4] [30], more than 90% [22,33], more than 80% [18,19,24,25,32], more than 70% [20,21,23], and the probability of this asymmetric distribution of risk values -which seems to indicate a protective effect -being chance is very low in some of these studies [21,23,26,27,30,31], while in other studies [19,22,24,25,32,33], as in the overall data, is practically zero. In Hardell's studies, over 90% of the risk values are above 1 (with 37% s.s.), and the probability of this distribution -supporting a carcinogenic effect due to MP use -being due to chance is almost zero.…”

“…It is possible too that the interval between introduction of mobile phones and occurrence of the tumour we studied was too short to observe an effect, if there is one, as acoustic neuroma is usually a slowly growing tumour". In addition, the previous Interphone data regarding the s.s. increased risk of ipsilateral acoustic neuromas in those using cellphones for at least 10 years [29,31] (Table 2) are not highlighted, and their weight is cancelled out since they are buried in the overall data of this study. Finally, of Hardell's articles on acoustic neuromas only three are cited; these are among the least significant (not quoted in the present review) and are discarded in a simple comment: "these results are not compatible with our findings", without further explanation.…”

“…The editorial of Cardis and Sadetzki takes further the remarks by Saracci and Samet, and leaves little doubt about the relevance of our criticisms, which we document on as follows ( Table 1): • of the 17 Interphone studies [16,[18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33], fewer than 10% of the exposed cases and controls had completed at least 10 years of cellphone latency or continued use, which means that over 90% had an inadequate exposure time. Since in most of the tumours 95%CI superior limit < 1 for OR<1, and 95%CI inferior limit > 1 for OR>1; 2 ORs decrease together with the increase of exposition and/or latency; n.r.…”

“…These data obviously are barely significant relative to today's intense use of cellphones, especially by those adopting them for work purposes. In Hardell's studies, MP use is reported to be more than 1000 hours for 194 cases and more than 2000 hours for 85 cases over at least 10 years, so that the average use of MPs ranges from over 16 to just more than 32 minutes per day for at least 10 years [1-4]; • in Interphone, the participation of the identified cases or controls in the study is low: 50% [24,30,31], 60% [18,20,28,32,33], 70% [16,19,21,23,25]. In Hardell's studies, participation is always much higher (88-90%) for both cases and controls [1,2]; • owing to the non-blind Interphone protocol, there is often a reduced participation in the study by the nonmobile users initially selected -in particular controls who are not affected by tumours, naturally less interested in the aims of the research than regular users, especially cases affected by tumours -and this represents a further factor of "dilution" of risk estimates.…”