@article {BocquillonP69, author = {Victor Bocquillon and Renaud Tamisier and Marie Destors and Muriel Salvat and Elisabeth Borrel and Jean-Louis P{\'e}pin}, title = {Prevalence and contributing factors for daytime and nocturnal hypoxia in chronic heart failure patients}, volume = {3}, number = {suppl 1}, elocation-id = {P69}, year = {2017}, doi = {10.1183/23120541.sleepandbreathing-2017.P69}, publisher = {European Respiratory Society}, abstract = {Despite clinical optimization of chronic heart failure (CHF), many CHF patients remain symptomatic. Oxygen-therapy is often prescribed in the most severe patients, but no evidence exists regarding the prevalence of patterns of hypoxia and their mechanisms.183 stable CHF patients, with optimized medical treatment, were enrolled. They underwent a cardiorespiratory sleep recording, a complete pulmonary function test and arterial blood gazes.86.3\% were men with a mean age of 67 years and BMI 27kg/m2. They were mainly in class II-III NYHA, with a mean LVEF of 38\%. Patients exhibited multiple comorbidities and airflow obstruction was present in 35.06\%. 4.37\% patients were hypoxic during both daytime and sleep but as many as 82.5\% were hypoxic during sleep. Nocturnal hypoxia was found in 87\% of patients and was explained by the presence of sleep disorder breathing (SDB) in all but 3 patients. SDB were either obstructive sleep apnea (OSAS) (59\%) or central sleep apnea (39\%) syndrome with a mean AHI of 29.59/h, Oxygen Desaturation Index of 27.09/h, time below 90\% of saturation of 18min with a mean nocturnal saturation of 93\%. Univariate analysis found that nocturnal hypoxia was associated with higher BMI and LVEF (\<35\%). In multivariate analysis, only SAS severity (p\<0.001) and diurnal PaO2 were significantly correlated with nocturnal hypoxia. In stable CHF patients, daytime hypoxia is rare but always associated with a worsening of hypoxia during sleep due to the presence of SDB. Nocturnal hypoxia is highly prevalent and always associated with the presence of SDB with a majority of OSAS. These distinct phenotypes particularly non-OSAS are important to better design Long term oxygen therapy studies in this population.}, URL = {https://openres.ersjournals.com/content/3/suppl_1/P69}, eprint = {https://openres.ersjournals.com/content}, journal = {ERJ Open Research} }