OSA is a syndrome caused by recurrent episodes of partial or complete pharyngeal collapse
during sleep. It is a common and progressive chronic disease that is responsible for a high
number of comorbidities and it is related to an increase in mortality, including a rise in the
rate of sudden cardiac death. OSA affects millions of people worldwide; it is a
heterogeneous condition with distinct phenotypes, varying from lean young adults with
maxillofacial abnormalities and limited IH, to obese middle aged OSA patients with
metabolic syndrome, obesity hypoventilation syndrome or overlap syndrome (i.e. a
combination of OSA and COPD). Two-thirds of HF patients exhibit CSA or OSA. OSA is
highly prevalent in specific populations, such as those with hypertension, stroke, coronary
heart disease and patients exhibiting arrhythmias. Sleep fragmentation and chronic IH, the
markers of OSA, induce intermediate mechanisms, such as oxidative stress, sympathetic
nervous system activation and systemic inflammation, responsible for symptoms and
This issue of the ERS Monograph begins by addressing the pathogenesis of OSA, with new
insights from animal models and integrated physiology. These chapters provide new clues
to understanding OSA-related cardiovascular morbidity, as well as ways of phenotyping
patients for better prediction of their response to different therapeutic modalities. Leg fluid
volume shift from the legs to the neck during the night, a recently demonstrated
mechanism that may precipitate UA collapse, is also put into clinical perspective. Another
recent hot topic is the link between OSA and cancer; the excess mortality associated with
OSA has not only been attributed to cardio-metabolic consequences but also to cancer.
This was first suggested in animal studies that demonstrated an association between IH,
carcinogenesis and the acceleration of tumour growth; this has recently been confirmed in
clinical and epidemiological studies.
The individual populations in which OSA is highly prevalent are considered in subsequent
chapters. Specific diagnostic strategies are necessary because OSA recognition modifies risk
stratification and requires therapeutic intervention. The authors provide state-of-the art
updates on various clinical scenarios, including OSA in children, during pregnancy, in
overlap and obesity hypoventilation syndromes and in patients undergoing bariatric surgery.
Copyright ©ERS 2015. Print ISBN: 978-1-84984-059-0. Online ISBN: 978-1-84984-060-6. Print ISSN: 2312-508X. Online ISSN: 2312-5098.
Correspondence: Jean-Louis Pépin, Laboratoire EFCR, CHU de Grenoble, BP217X, 38043 Grenoble cedex 09, France.
Dept, Hospital Universitari Arnau de Vilanova and Santa Maria, IRB Lleida, Lleida, Spain.
Biomédica en Red de Enfermedades Respiratorias (CIBERES), Madrid, Spain.
Alpes University, HP2 Laboratory, Grenoble,
U1042, Grenoble, France.
Universitaire de Physiologie et Sommeil, Pôle Thorax et Vaisseaux, Hôpital
A. Michallon, Grenoble, France.
viii ERS Monogr 2015; 67: viii–ix. DOI: 10.1183/2312508X.10000615