Study type: Epidemiological study (observational study)

Combined risk estimates for two German population-based case-control studies on residential magnetic fields and childhood acute leukemia. epidem.

Published in: Epidemiology 1998; 9 (1): 92-94

Aim of study (acc. to author)

To evaluate the risk for childhood acute leukemia and residential magnetic fields in a pooled analysis of two case-control studies (publication 975) in different German regions.

Further details

Exposure to magnetic fields were estimated by two different methods of exposure assessment: measurement of the magnetic field over a period of 24 hours in the child's bedroom at the residence where the child had been living for the longest period before date of diagnosis, and spot measurements at all residences where the child had been living for more than one year. Exposure was categorized in high (0.2 µT and more) and low ( below 0.2 µT).

Endpoint/type of risk estimation

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

Exposure

Assessment

Exposure groups

Group Description
Reference group 1 median of 24h-measurement in the child's bedroom: < 0.2 µT
Group 2 median of 24h-measurement in the child's bedroom: ≥ 0.2 µT
Reference group 3 mean of 24h-measurement in the child's bedroom: < 0.2 µT
Group 4 mean of 24h-measurement in the child's bedroom: ≥ 0.2 µT
Reference group 5 median during night: < 0.2 µT
Group 6 median during night: ≥ 0.2 µT
Reference group 7 mean of medians of 24h-measurements in the child's bedroom and livingroom: < 0.2 µT
Group 8 mean of medians of 24h-measurements in the child's bedroom and livingroom: ≥ 0.2 µT
Reference group 9 spot measurement at residence where the child lived longest: < 0.2 µT
Group 10 spot measurement at residence where the child lived longest: ≥ 0.2 µT
Reference group 11 maximum of spot measurement at all residences where the child lived for > 1 year: < 0.2 µT
Group 12 maximum of spot measurement at all residences where the child lived for > 1 year: ≥ 0.2 µT

Population

Case group

Control group

Study size

Cases Controls
Eligible 283 -
Evaluable 176 414
Statistical analysis method: (adjustment: )

Conclusion (acc. to author)

11.5 % of the children in East-Berlin, 4.9 % in West-Berlin, and 1.5 % in Lower Saxony were exposed to median magnetic fields above 0.2 µT.
A non-significantly evelated risk for childhood leukemia and a median of the 24h-measurement in the child's bedroom above 0.2 µT was observed. Significant associations were observed for younger children (≤ 4 years) and for children exposed to magnetic fields above 0.2 µT during the night. The results of this study based on measured magnetic field strengths gave some support to the hypothesis that evalated exposure to magnetic fields may be associated with childhood leukemia.

Limitations (acc. to author)

The participation rate of eligble subjects, especially in Berlin, was low.

Study funded by

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