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Analytic Choices Shape Genomic Risk Estimates from Electronic Health Records: Coronary Heart Disease in eMERGE IV
Jingheng H Chen1, Sarah A Knerr1,2, David L Veenstra3
1Institute of Public Health Genetics, University of Washington, Seattle, WA, USA.
Analytic choices in electronic health records (EHR) studies impact coronary heart disease (CHD) risk estimates. Case definition affects relative risk, while EHR entry time influences cumulative incidence, not hazard ratios.
Area of Science:
- Genomic epidemiology
- Biostatistics
- Health informatics
Background:
- Electronic health records (EHR) are crucial for genomic studies.
- Challenges exist in accurately identifying cases and observation start times within EHR data.
- The eMERGE IV study investigated these challenges in coronary heart disease (CHD) research.
Purpose of the Study:
- To evaluate how analytical assumptions on case ascertainment and EHR entry time influence genetic risk estimations for CHD.
- To compare different methods of defining CHD cases using EHR and self-report data.
- To assess the impact of varying observation start times on time-to-event analyses.
Main Methods:
- Compared EHR-phenotyped CHD cases with survey-ascertained cases.
- Utilized multivariate relative risk regression for monogenic and polygenic risk scores (PRS) under three case definitions.
- Performed time-to-event analyses using Kaplan-Meier and Cox proportional hazards models with three entry time specifications.
Main Results:
- Agreement between EHR and self-reported CHD cases was 37.2%, with EHR showing higher accuracy.
- High PRS was associated with significantly higher relative risk (RR) for EHR-defined (2.05), self-reported (1.49), and combined (1.66) CHD.
- Alternative EHR entry times affected cumulative incidence but minimally impacted hazard ratios.
Conclusions:
- The selection of case definition significantly influences relative risk estimates in EHR and survey-based genetic studies.
- EHR entry time specifications impact absolute cumulative incidence but have minimal effect on hazard ratios.
- These findings underscore the importance of analytical choices in EHR data utilization for genomic research.
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