Epidemiological study (observational study)

Pituitary tumor risk in relation to mobile phone use: A case-control study epidem.

By: Shrestha M, Raitanen J, Salminen T, Lahkola A, Auvinen A

Published in: Acta Oncol 2015; 54 (8): 1159-1165

Aim of study (acc. to author)

A case-control study was conducted in Finland to evaluate the association between pituitary tumor risk and mobile phone use.

Further details

The study sample represents a subset of the Finnish Interphone study. Regular use of a mobile phone was defined as at least once a week for at least six months.

Endpoint/type of risk estimation

brain tumor: pituitary tumor

Type of risk estimation:

incidence

(odds ratio (OR))

Exposure

- mobile communications
- analog mobile phone
- digital mobile phone
- GSM
- NMT

Assessment

interview: use of mobile phones including start and end dates, frequency of use, types of phone, use of hands-free devices
calculation: cumulative hours of use calculated from the average number and duration of calls

Exposure groups

Group	Description
Reference group 1	ever use of mobile phone: no
Group 2	ever use of mobile phone: yes
Reference group 3	never or nonregular use
Group 4	regular use
Group 5	years since first use: 1.5 - 4.9
Group 6	years since first use: 5.0 - 9.9
Group 7	years since first use: ≥ 10
Group 8	total duration of use: 1.5 - 4.9 years
Group 9	total duration of use: 5.0 - 9.9 years
Group 10	total duration of use: ≥10 years
Group 11	cumulative number of calls: < 3170
Group 12	cumulative number of calls: 3170 - 13769
Group 13	cumulative number of calls: > 13769
Group 14	cumulative use: < 214 hours
Group 15	cumulative use: 214 - 867 hours
Group 16	cumulative use: > 867 hours
Group 17	cumulative number of calls by time since first use: < 10 years
Group 18	cumulative number of calls by time since first use: ≥ 10 years (< 2190 calls)
Group 19	cumulative number of calls by time since first use: ≥ 10 years (≥ 2190 calls)
Group 20	cumulative hours of use by time since first use: < 10 years
Group 21	cumulative hours of use by time since first use: ≥ 10 years (< 188 hours)
Group 22	cumulative hours of use by time since first use: ≥ 10 years (≥ 188 hours)

Population

Group:
- men
- women
Age: 20–69 years
Observation period: 2000 - 2002
Study location: Finland

Case group

Characteristics: pituitary tumor, histologically confirmed or based on unequivocal diagnostic imaging
Data source: neurosurgery departments of all five university hospitals in Finland

Control group

Selection:
- population-based
Matching:
- sex
- age
- area
- case:control = 1:3

Study size

	Cases	Controls
Eligible	85	-
Evaluable	80	240

Statistical analysis method:

conditional logistic regression

Results (acc. to author)

A reduced odds ratio was seen among regular mobile phone users (OR 0.39, CI 0.21-0.72) compared to never/non-regular users, possibly reflecting methodological limitations. The pituitary tumor risk was not increased in relation to duration of use, cumulative hours of use, or cumulative number of calls.
The authors conclude that no excess pituitary tumor risk associated with short- or medium-term use of mobile phones was observed.

Study funded by

Academy of Finland
Emil Aaltonen Foundation, Finland
European Union (EU)/European Commission
GSM Association, UK/Ireland
Mobile Manufacturers Forum (MMF), Belgium
Quality of Life and Management of Living Resources program of European Union
University of Tampere, Finland

Leng L et al. (2016): Etiology of Pituitary Tumors: A Case Control Study
Benson VS et al. (2013): Mobile phone use and risk of brain neoplasms and other cancers: prospective study
Myung SK et al. (2009): Mobile phone use and risk of tumors: a meta-analysis
Schoemaker MJ et al. (2009): Risk of pituitary tumors in cellular phone users: a case-control study
Takebayashi T et al. (2008): Mobile phone use, exposure to radiofrequency electromagnetic field, and brain tumour: a case-control study