Risk for Glioma Triples With Long-Term Cell Phone Use
Pauline Anderson, Medscape Public Health and Prevention, Jan 14, 2015
|Phone Use||Odds Ratio (95% Confidence Interval)|
|Mobile phone use > 1 year||1.3 (1.1 - 1.6)|
|Cordless phone use > 1 year||1.4 (1.1 - 1.7)|
|Mobile phone use > 25 years||3.0 (1.7 - 5.2)|
- The investigators pooled data from 2 case-control studies of malignant brain tumors from patients diagnosed in Sweden during 1997 to 2003 (diagnosis at ages 20 - 80 years) and 2007 to 2009 (ages 18 - 75 years).
- The investigators included only cases in which the tumor was confirmed by histopathologic examination.
- Population-based control participants were matched for age and gender.
- Questionnaires allowed determination of exposures to cell and cordless phone use.
- Unconditional regression analysis used the entire reference group, with adjustment for gender, age, year of diagnosis, and socioeconomic index.
- Response rates were 89% for patients (n = 1498) and 87% for control participants (n = 3530).
- Among the patients, 92% had glioma, of which 50.3% of these tumors were highly malignant glioblastoma multiforme (astrocytoma grade 4).
- Overall, mobile phone use was associated with a 30% increased risk for glioma (OR, 1.3; 95% CI, 1.1 - 1.6).
- For mobile phone use in the latency group of more than 25 years, the risk for glioma was tripled that in the control participants (OR, 3.0; 95% CI, 1.7 - 5.2).
- Use of cordless phones was associated with an overall 40% increased risk for glioma (OR, 1.4; 95% CI, 1.1 - 1.7), with risk increased further to 70% in the latency group of 15 to 20 years (OR, 1.7; 95% CI, 1.1 - 2.5).
- There were statistically significant increases in OR both per 100 hours of cumulative use, and per year of latency for mobile and cordless phone use.
- The risk was greatest for ipsilateral glioma (OR, 1.8 for mobile phone use; 95% CI, 1.4 - 2.2 and OR, 1.7 for cordless phone use; 95% CI, 1.3 - 2.1).
- In terms of location, the risk was greatest for glioma in the temporal and overlapping lobes, corresponding to the region of highest RF-EMF exposure.
- Beginning mobile or cordless phone use before age 20 years was associated with a higher risk for glioma compared with mobile or cordless phone use beginning at later ages.
- Although glioma risk was higher with use of 3G mobile phones, this was based on short latency and a small sample of exposed cases.
- Limitations of this study include possible recall bias or observational bias and relatively small numbers of patients and control participants in certain subgroups.
- Possible precautions to limit RF-EMF exposure during mobile or cordless phone use include using hands-free phones with a loud speaker and text messaging instead of telephoning.
- The risk for glioma is increased with cell and cordless phone use, based on an analysis of pooled case-control studies in Sweden.
- The risk associated with cell and cordless phone use is especially increased for ipsilateral glioma of the temporal and overlapping lobes, particularly for longer exposure starting at younger ages.
Joel M. Moskowitz, Ph.D., Director
Center for Family and Community Health
School of Public Health
University of California, Berkeley
Electromagnetic Radiation Safety
News Releases: http://pressroom.prlog.org/