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Disease latency bias and the protective effect of metformin against age-related macular degeneration

Eye (2024)Cite this article

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In recent years, there has been an increase in the publication of epidemiologic studies in the area of ophthalmology using Big Data. Advances in epidemiologic methodology along with access to large health claims databases has allowed researchers to address important vision related questions. However, observational studies using Big Data also pose unique methodologic challenges. Some of these challenges include controlling for confounders or examining other well-established biases such as measurement error and selection bias [1, 2]. Here we introduce another important bias that might affect ocular epidemiologic studies, disease latency bias (DLB).

DLB occurs when early symptoms of a disease can affect exposure before the disease is diagnosed. A good example is age-related macular degeneration (AMD) where visual deficits can occur years prior to disease diagnosis [3]. To better describe DLB we will use the example of the effect of metformin on the risk of AMD.

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Fig. 1: Disease latency bias in patients on metformin diagnosed with AMD.

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Data sharing is not applicable to this article as no datasets were generated or analysed during the current study.

References

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Authors and Affiliations

  1. Department of Ophthalmology and Visual Sciences, Faculty of Medicine, University of British Columbia, Vancouver, BC, Canada

    Jennifer Y. M. Ling & Mahyar Etminan

  2. Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran

    Mohammad A. Mansournia

Authors
  1. Jennifer Y. M. Ling
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  2. Mohammad A. Mansournia
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  3. Mahyar Etminan
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Contributions

JYML – study concept, analysis, manuscript preparation; MAM – analysis, manuscript preparation; ME – study concept, analysis, manuscript preparation. All authors have reviewed and approved the final version of this manuscript.

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Correspondence to Mahyar Etminan.

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The authors declare no competing interests.

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Ling, J.Y.M., Mansournia, M.A. & Etminan, M. Disease latency bias and the protective effect of metformin against age-related macular degeneration. Eye (2024). https://doi.org/10.1038/s41433-024-02993-7

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  • DOI: https://doi.org/10.1038/s41433-024-02993-7

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