Proceedings of the Twenty-Ninth AAAI Conference on Artificial Intelligence Clustering Longitudinal Clinical Marker Trajectories from Electronic Health Data: Applications to Phenotyping and Endotype Discovery Peter Schulam Fredrick Wigley Suchi Saria Department of Computer Science Division of Rheumatology Department of Computer Science Johns Hopkins University Johns Hopkins School of Medicine Department of Health Policy & Mgmt. 3400 N. Charles St. 733. N. Broadway Johns Hopkins University Baltimore, MD 21218 Baltimore, MD 21205 3400 N. Charles St.
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[email protected] Abstract more thorough retrospective or prospective study to confirm their existence (e.g. Barr et al. 1999). Recently, however, Diseases such as autism, cardiovascular disease, and the au- literature in the medical community has noted the need for toimmune disorders are difficult to treat because of the re- markable degree of variation among affected individuals. more objective methods for discovering subtypes (De Keu- Subtyping research seeks to refine the definition of such com- lenaer and Brutsaert 2009). Growing repositories of health plex, multi-organ diseases by identifying homogeneous pa- data stored in electronic health record (EHR) databases tient subgroups. In this paper, we propose the Probabilis- and patient registries (Blumenthal 2009; Shea and Hripc- tic Subtyping Model (PSM) to identify subgroups based on sak 2010) present an exciting opportunity to identify disease clustering individual clinical severity markers. This task is subtypes in an objective, data-driven manner using tools challenging due to the presence of nuisance variability— from machine learning that can help to tackle the problem variations in measurements that are not due to disease of combing through these massive databases.