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Published on: December 11, 2016
Drug-Wide Association Study (DWAS): Challenges and Opportunities
Youjin Wang1, Shahinaz M Gadalla2
1Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, Maryland. youjin.wang@nih.gov.
Abstract:
Cancer risk associations with commonly prescribed medications have been mainly evaluated in hypothesis-driven studies that focus on one drug at a time. Agnostic drug-wide association studies (DWAS) offer an alternative approach to simultaneously evaluate associations between a large number of drugs with one or more cancers using large-scale electronic health records. Although cancer DWAS approaches are promising, a number of challenges limit their applicability. This includes the high likelihood of false positivity; lack of biological considerations; and methodological shortcomings, such as inability to tightly control for confounders. As such, the value of DWAS is currently restricted to hypothesis generation with detected signals needing further evaluation. In this commentary, we discuss those challenges in more detail and summarize the approaches to overcome them by using published cancer DWAS studies, including the accompanied article by Støer and colleagues. Despite current concerns, DWAS future is filled with opportunities for developing innovative analytic methods and techniques that incorporate pharmacology, epidemiology, cancer biology, and genetics.See related article by Støer et al., p. 682.
Insights
Drug-wide association studies (DWAS) can identify potential cancer risks from medications using electronic health records. However, challenges like false positives and confounding factors require further research and validation for reliable findings.
Area of Science:
- Pharmacology
- Oncology
- Epidemiology
Background:
- Traditional studies on medication and cancer risk focus on one drug at a time.
- Agnostic drug-wide association studies (DWAS) offer a broader approach using electronic health records.
Purpose of the Study:
- To discuss the challenges and potential solutions for cancer DWAS.
- To highlight the future opportunities for improving DWAS methodology.
Main Methods:
- Utilizing large-scale electronic health records for DWAS.
- Reviewing published cancer DWAS studies and their methodologies.
Main Results:
- Cancer DWAS can simultaneously evaluate numerous drugs for cancer associations.
- Current DWAS approaches face challenges including false positivity and confounding.
Conclusions:
- DWAS are valuable for hypothesis generation but require further validation.
- Future DWAS development needs to integrate pharmacology, epidemiology, cancer biology, and genetics.
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