Clinical Knowledge Extraction via Sparse Embedding Regression (KESER) with Multi-Center Large Scale Electronic Health Record Data

ObjectiveThe increasing availability of Electronic Health Record (EHR) systems has created enormous potential for translational research. Even with a working knowledge of EHR, it is difficult to know all the relevant codes related to a phenotype due to the large number of codes available. Traditional data mining approaches often require the use of patient-level data, which hinders the ability to share data across institutions to establish a cooperative and integrated knowledge network. In this project, we demonstrate that multi-center large-scale code embeddings can be used to efficiently identify relevant features related to a disease or condition of interest. MethodWe constructed large-scale code embeddings for a wide range of codified concepts, including diagnosis codes, medications, procedures, and laboratory tests from EHRs from two large medical centers. We developed knowledge extraction via sparse embedding regression (KESER) for feature selection and integrative network analysis based on the trained code embeddings. We evaluated the quality of the code embeddings and assessed the performance of KESER in feature selection for eight diseases. Besides, we developed an integrated clinical knowledge map combining embedding data from both institutions. ResultsThe features selected by KESER were comprehensive compared to lists of codified data generated by domain experts. Additionally, features identified automatically via KESER used in the development of phenotype algorithms resulted in comparable performance to those built upon features selected manually or identified via existing feature selection methods with patient-level data. The knowledge map created using an integrative analysis identified disease-disease and disease-drug pairs more accurately compared to those identified using single institution data. ConclusionAnalysis of code embeddings via KESER can effectively reveal clinical knowledge and infer relatedness among diseases, treatment, procedures, and laboratory measurement. This approach automates the grouping of clinical features facilitating studies of the condition. KESER bypasses the need for patient-level data in individual analyses providing a significant advance in enabling multi-center studies using EHR data.