Hypertension, as a cardiovascular risk factor, is a public health issue for which many clinical practice guidelines (CPGs) are published. In order to build the knowledge base of a clinical decision support system for the management of hypertension, we analysed three contemporary (2013) CPGs written in French on hypertension in a knowledge modelling perspective. We developed a semi-automated method using natural language processing called term extraction. Relevant candidate terms have been mapped to medical concepts to produce the conceptual coverage of each CPG. Only 53% of the 88 identified concepts were shared by the three guidelines. While sharing concepts does not warrantee that CPGs contents are similar, this also emphasizes guideline specificities. Such specificities could enrich the knowledge base of decision support systems by broadening their scope.