Coronary Artery Disease (CAD) is not only the most common form of heart disease, but also the leading cause of death in both men and women[1]. We present a system that is able to automatically predict whether patients develop coronary artery disease based on their narrative medical histories, i.e., clinical free text. Although the free text in medical records has been used in several studies for identifying risk factors of coronary artery disease, to the best of our knowledge our work marks the first attempt at automatically predicting development of CAD. We tackle this task on a small corpus of diabetic patients. The size of this corpus makes it important to limit the number of features in order to avoid overfitting. We propose an ontology-guided approach to feature extraction, and compare it with two classic feature selection techniques. Our system achieves state-of-the-art performance of 77.4% F1 score.

In medical practices, doctors detail patients’ care plan via discharge summaries written in the form of unstructured free texts, which among the others contain medication names and prescription information. Extracting prescriptions from discharge summaries is challenging due to the way these documents are written. Handwritten rules and medical gazetteers have proven to be useful for this purpose but come with limitations on performance, scalability, and generalizability. We instead present a machine learning approach to extract and organize medication names and prescription information into individual entries. Our approach utilizes word embeddings and tackles the task in two extraction steps, both of which are treated as sequence labeling problems. When evaluated on the 2009 i2b2 Challenge official benchmark set, the proposed approach achieves a horizontal phrase-level F1-measure of 0.864, which to the best of our knowledge represents an improvement over the current state-of-the-art.