Epidemiological study (observational study)

Cellular phones, cordless phones, and the risks of glioma and meningioma (Interphone Study Group, Germany).

Published in: Am J Epidemiol 2006; 163 (6): 512-520

Aim of study (acc. to author)

To examine whether the risk of glioma and meningioma is associated with the use of cellular phones or cordless phones, a population-based case-control study was conducted in Germany.

Further details

This study is part of the INTERPHONE project.
Regular use of cellular phone was defined as at least one incoming or outgoing call per week for 6 months or more.

Endpoint/type of risk estimation

Type of risk estimation:
  • incidence
(odds ratio (OR))

Exposure

Assessment

  • interview: use of cellular phone, type, starting and cessation date, numbers of call made and received, duration of calls, use of hands-free devices, use of analog or DECT cordless phone, type, starting and stopping dates, location of base station within house
  • calculation: lifetime number of calls and lifetime hours of cellular phone use

Exposure groups

Reference group 1 regular cellular phone use: never
Group 2 regular cellular phone use: ever
Group 3 time since first regular use: never, < 1 year
Group 4 time since first regular use: 1-4 years
Group 5 time since first regular use: ≥ 5 years
Group 6 time since first regular use: 5-9 years
Group 7 time since first regular use: ≥ 10 years
Reference group 8 lifetime number of calls: never use
Group 9 lifetime number of calls: ≤ 1176
Group 10 lifetime number of calls: > 1176 ≤ 4350
Group 11 lifetime number of calls: > 4350
Reference group 12 lifetime duration of calls: never use
Group 13 lifetime duration of calls: ≤ 44
Group 14 lifetime duration of calls: > 44 ≤ 195
Group 15 lifetime duration of calls: > 195
Reference group 16 intensity of use: never
Group 17 intensity of use: < 30 minutes/day
Group 18 intensity of use: ≥ 30 minutes/day
Reference group 19 duration of calls ≥ 5 years before reference date: never
Group 20 duration of calls ≥ 5 years before reference date: < 5 years
Group 21 duration of calls ≥ 5 years before reference date: ≥ 5 years, ≤ 34.5 hours
Group 22 duration of calls ≥ 5 years before reference date: ≥ 5 years, > 34.5 hours
Reference group 23 cordless phone use: no
Group 24 cordless phone use: yes (at home or at work)
Group 25 cordless phone use: yes, at work only
Group 26 cordless phone use: yes, at home only
Group 27 cordless phone use: yes, at home and at work
Reference group 28 time since first cordless phone use: no use or < 5 years
Group 29 time since first cordless phone use: 1-4 years
Group 30 time since first cordless phone use: ≥ 5 years
Reference group 31 time since first use (cordless and/or cellular phones): no use or < 1 year
Group 32 time since first use (cordless and/or cellular phones): 1-4 years
Group 33 time since first use (cordless and/or cellular phones): ≥ 5 years

Population

  • Group:
    • men
    • women
  • Age: 30–69 yr
  • Observation period: October 2000 - October 2003
  • Study location: Germany (3 study regions)

Case group

  • Characteristics: glioma and meningioma, histologically confirmed
  • Data source: neurosurgical clinics in Bielefeld, Heidelberg, Mainz and Mannheim, Germany
  • Exclusion criteria: no histological confirmation, recurrent tumors, insufficient knowledge of the German language, main residence outside the study region

Control group

  • Selection:
    • population-based
  • Matching:
    • sex
    • age
    • area
    • case:control = 1:2
  • Exclusion criteria: moved out of study region, insufficient knowledge of the German language, main residence outside the study region

Study size

Cases Controls
Eligible 891 2,449
Participants 747 1,535
Participation rate 84 63
Other: glioma: 460 cases eligible, 366 participating; meningioma: 431 cases eligible, 381 participating
Statistical analysis method:
  • conditional logistic regression
( adjustment:
  • age
  • sex
  • socioeconomic status
  • study center, living in a city (≥ 100,000 inhabitants vs. < 100,000)
)

Conclusion (acc. to author)

The results did not indicate an overall increased risk of glioma or meningioma among regular cellular telephone users. An elevated risk of glioma was observed among persons who had used cellular phones for 10 or more years, but based on small numbers. No association between cordless telephone use and the risks of glioma or meningioma was found. An increased risk of high-grade glioma was observed for women, which might be a chance finding.

Limitations (acc. to author)

The number of cellular phone users for 10 years or more was low and effects of recall bias cannot to be ruled out.

Study funded by

  • Bundesamt für Strahlenschutz (BfS; Federal Office for Radiation Protection), Salzgitter, Germany
  • European Union (EU)/European Commission
  • Deutsches Mobilfunk Forschungsprogramm (DMF; German Mobile Phone Research Programme) at Federal Office for Radiation Protection (BfS)
  • MAIFOR Program (Mainzer Forschungsförderungsprogramm) of the University of Mainz, Germany
  • GSM Association, UK/Ireland
  • Mobile Manufacturers Forum (MMF), Belgium
  • Ministerium für Umwelt und Verkehr, Baden-Württemberg (Ministry for the Environment and Traffic of the state of Baden-Württemberg), Germany
  • Ministerium für Umwelt und Naturschutz, Landwirtschaft und Verbraucherschutz, Nordrhein-Westfalen (Ministry for the Environment of the state of North Rhine-Westphalia), Germany
  • Bundesministerium für Umwelt, Naturschutz und Reaktorsicherheit (Federal Ministry of the Environment, Nature Conservation, and Nuclear Safety), Germany
  • International Union against Cancer (UICC; Union Internationale Contre le Cancer), Switzerland

Comments on this article

  • Morgan LL (2006): Re: "Cellular phones, cordless phones, and the risks of glioma and meningioma (Interphone Study Group, Germany)".

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