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The sensitivity of reported effects of EMF on childhood leukemia to uncontrolled confounding by residential mobility: a hybrid simulation study and an empirical analysis using CAPS data

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Abstract

Purpose

Residential mobility is considered as a potential source of confounding in studies assessing environmental exposures, including in studies of electromagnetic field (EMF) exposures and childhood leukemia.

Methods

We present a hybrid simulation study where we simulate a synthetic dataset based on an existing study and use it to assess the sensitivity of EMF–leukemia associations to different scenarios of uncontrolled confounding by mobility under two major hypotheses of the infectious etiology of childhood leukemia. We then used the findings to conduct sensitivity analysis and empirically offset the potential bias due to unmeasured mobility in the California Power Line Study dataset.

Results

As expected, the stronger the assumed relationship between mobility and exposure and outcome, the greater the potential bias. However, no scenario created a bias strong enough to completely explain away previously observed associations.

Conclusions

We conclude that uncontrolled confounding by residential mobility had some impact on the estimated effect of EMF exposures on childhood leukemia, but that it was unlikely to be the primary explanation behind previously observed largely consistent, but unexplained associations.

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References

  1. Sahl JD (1994) Viral contacts confound studies of childhood leukemia and high-voltage transmission lines. Cancer Causes Control 5(3):279–283

    Article  CAS  PubMed  Google Scholar 

  2. Kheifets L, Swanson J, Yuan Y, Kusters C, Vergara X (2017) Comparative analyses of studies of childhood leukemia and magnetic fields, radon and gamma radiation. J Radiol Prot 37(2):459–491. https://doi.org/10.1088/1361-6498/aa5fc7

    Article  PubMed  Google Scholar 

  3. Amoon AT, Oksuzyan S, Crespi CM, Arah OA, Cockburn M, Vergara X et al (2018) Residential mobility and childhood leukemia. Environ Res 164:459–466. https://doi.org/10.1016/j.envres.2018.03.016

    Article  CAS  PubMed  Google Scholar 

  4. Urayama KY, Von Behren J, Reynolds P, Hertz A, Does M, Buffler PA (2009) Factors associated with residential mobility in children with leukemia: implications for assigning exposures. Ann Epidemiol 19(11):834–840. https://doi.org/10.1016/j.annepidem.2009.03.001

    Article  PubMed  PubMed Central  Google Scholar 

  5. Hatch EE, Kleinerman RA, Linet MS, Tarone RE, Kaune WT, Auvinen A et al (2000) Do confounding or selection factors of residential wiring codes and magnetic fields distort findings of electromagnetic fields studies? Epidemiology 11(2):189–198

    Article  CAS  PubMed  Google Scholar 

  6. Wartenberg D, Greenberg MR, Harris G (2010) Environmental justice: a contrary finding for the case of high-voltage electric power transmission lines. J Expo Sci Environ Epidemiol 20(3):237–244. https://doi.org/10.1038/jes.2009.11

    Article  PubMed  Google Scholar 

  7. Feychting M, Ahlbom A (1993) Magnetic fields and cancer in children residing near Swedish high-voltage power lines. Am J Epidemiol 138(7):467–481

    Article  CAS  PubMed  Google Scholar 

  8. Vergara XP, Kavet R, Crespi CM, Hooper C, Silva JM, Kheifets L (2015) Estimating magnetic fields of homes near transmission lines in the California Power Line Study. Environ Res 140:514–523. https://doi.org/10.1016/j.envres.2015.04.020

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  9. McCarthy GW, Rohe WM, van Zandt S. The economic benefits and costs of homeownership: A critical assessment of the research. Research Institute for Housing America; 2001

  10. Kinlen LJ (2012) An examination, with a meta-analysis, of studies of childhood leukaemia in relation to population mixing. Br J Cancer 107(7):1163–1168. https://doi.org/10.1038/bjc.2012.402

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Greaves M (2018) A causal mechanism for childhood acute lymphoblastic leukaemia. Nat Rev Cancer 18(8):471–484. https://doi.org/10.1038/s41568-018-0015-6

    Article  CAS  PubMed  Google Scholar 

  12. Greaves M (2006) Infection, immune responses and the aetiology of childhood leukaemia. Nat Rev Cancer 6(3):193–203. https://doi.org/10.1038/nrc1816

    Article  CAS  PubMed  Google Scholar 

  13. Urayama KY, Buffler PA, Gallagher ER, Ayoob JM, Ma X (2010) A meta-analysis of the association between day-care attendance and childhood acute lymphoblastic leukaemia. Int J Epidemiol 39(3):718–732. https://doi.org/10.1093/ije/dyp378

    Article  PubMed  PubMed Central  Google Scholar 

  14. Urayama KY, Ma X, Selvin S, Metayer C, Chokkalingam AP, Wiemels JL et al (2011) Early life exposure to infections and risk of childhood acute lymphoblastic leukemia. Int J Cancer 128(7):1632–1643. https://doi.org/10.1002/ijc.25752

    Article  CAS  PubMed  Google Scholar 

  15. Westergaard T, Andersen PK, Pedersen JB, Olsen JH, Frisch M, Sorensen HT et al (1997) Birth characteristics, sibling patterns, and acute leukemia risk in childhood: a population-based cohort study. J Natl Cancer Inst 89(13):939–947

    Article  CAS  PubMed  Google Scholar 

  16. Amitay EL, Keinan-Boker L (2015) Breastfeeding and childhood leukemia incidence: a meta-analysis and systematic review. JAMA Pediatr 169(6):e151025. https://doi.org/10.1001/jamapediatrics.2015.1025

    Article  PubMed  Google Scholar 

  17. Ma X, Buffler PA, Wiemels JL, Selvin S, Metayer C, Loh M et al (2005) Ethnic difference in daycare attendance, early infections, and risk of childhood acute lymphoblastic leukemia. Cancer Epidemiol Biomarkers Prev 14(8):1928–1934. https://doi.org/10.1158/1055-9965.EPI-05-0115

    Article  PubMed  Google Scholar 

  18. Sudan M, Arah OA, Olsen J, Kheifets L (2016) Reported associations between asthma and acute lymphoblastic leukemia: insights from a hybrid simulation study. Eur J Epidemiol 31(6):593–602. https://doi.org/10.1007/s10654-016-0126-x

    Article  CAS  PubMed  Google Scholar 

  19. Kheifets L, Crespi CM, Hooper C, Oksuzyan S, Cockburn M, Ly T et al (2015) Epidemiologic study of residential proximity to transmission lines and childhood cancer in California: description of design, epidemiologic methods and study population. J Expo Sci Environ Epidemiol 25(1):45–52. https://doi.org/10.1038/jes.2013.48

    Article  PubMed  Google Scholar 

  20. Kheifets L, Crespi CM, Hooper C, Cockburn M, Amoon AT, Vergara XP (2017) Residential magnetic fields exposure and childhood leukemia: a population-based case-control study in California. Cancer Causes Control 28(10):1117–1123. https://doi.org/10.1007/s10552-017-0951-6

    Article  PubMed  PubMed Central  Google Scholar 

  21. Crespi CM, Vergara XP, Hooper C, Oksuzyan S, Wu S, Cockburn M et al (2016) Childhood leukaemia and distance from power lines in California: a population-based case-control study. Br J Cancer 115(1):122–128. https://doi.org/10.1038/bjc.2016.142

    Article  PubMed  PubMed Central  Google Scholar 

  22. McNally RJ, Eden TO (2004) An infectious aetiology for childhood acute leukaemia: a review of the evidence. Br J Haematol 127(3):243–263. https://doi.org/10.1111/j.1365-2141.2004.05166.x

    Article  PubMed  Google Scholar 

  23. Arah OA (2017) Bias analysis for uncontrolled confounding in the health sciences. Annu Rev Public Health 38:23–38. https://doi.org/10.1146/annurev-publhealth-032315-021644

    Article  PubMed  Google Scholar 

  24. Arah OA, Chiba Y, Greenland S (2008) Bias formulas for external adjustment and sensitivity analysis of unmeasured confounders. Ann Epidemiol 18(8):637–646. https://doi.org/10.1016/j.annepidem.2008.04.003

    Article  PubMed  Google Scholar 

  25. Green LM, Miller AB, Agnew DA, Greenberg ML, Li J, Villeneuve PJ et al (1999) Childhood leukemia and personal monitoring of residential exposures to electric and magnetic fields in Ontario, Canada. Cancer Causes Control 10(3):233–243

    Article  CAS  PubMed  Google Scholar 

  26. Kleinerman RA, Linet MS, Hatch EE, Wacholder S, Tarone RE, Severson RK et al (1997) Magnetic field exposure assessment in a case-control study of childhood leukemia. Epidemiology 8(5):575–583

    Article  CAS  PubMed  Google Scholar 

  27. McBride ML, Gallagher RP, Theriault G, Armstrong BG, Tamaro S, Spinelli JJ et al (1999) Power-frequency electric and magnetic fields and risk of childhood leukemia in Canada. Am J Epidemiol 149(9):831–842

    Article  CAS  PubMed  Google Scholar 

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Acknowledgments

We thank Roch Nianogo, Madhuri Sudan, and Yongfu Yu for their assistance with the software coding on this project. This work was supported by the Electric Power Research Institute.

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Authors and Affiliations

  1. Department of Epidemiology, Fielding School of Public Health, University of California, Los Angeles (UCLA), 650 Charles E. Young Drive South, Los Angeles, CA, 90095-1772, USA

    Aryana T. Amoon, Onyebuchi A. Arah & Leeka Kheifets

  2. Department of Statistics, UCLA College of Letters and Science, Los Angeles, CA, USA

    Onyebuchi A. Arah

Authors
  1. Aryana T. Amoon
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  2. Onyebuchi A. Arah
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  3. Leeka Kheifets
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Correspondence to Aryana T. Amoon.

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The authors declare no conflicts of interest.

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CAPS was approved by University of California, Los Angeles Office for the Protection of Research Subjects.

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Amoon, A.T., Arah, O.A. & Kheifets, L. The sensitivity of reported effects of EMF on childhood leukemia to uncontrolled confounding by residential mobility: a hybrid simulation study and an empirical analysis using CAPS data. Cancer Causes Control 30, 901–908 (2019). https://doi.org/10.1007/s10552-019-01189-9

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  • DOI: https://doi.org/10.1007/s10552-019-01189-9

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