O038 Obstructive Sleep Apnoea Prevalence and Severity in a Specialist Heart Failure with Preserved Ejection Fraction (HFpEF) Clinic

Heart Failure with Preserved Ejection Fraction (HFpEF) is a debilitating, incurable form of HF associated with a normal left ventricular ejection fraction and elevated ventricular filling pressures. While Obstructive Sleep Apnoea (OSA) is common in HFpEF and OSA treatment may be associated with improved outcomes, the causal role of OSA in the pathophysiology of HFpEF remains unclear. Accordingly, accurate diagnosis and tracking of OSA in HFpEF patients is emerging as a potentially important approach for impacting prognosis. This study sought to identify the prevalence and severity of OSA in consecutive patients referred to a recently established tertiary hospital HFpEF clinic. All patients were confirmed to have HFpEF using standard clinical approaches and completed the Epworth Sleepiness Scale (ESS) to screen for sleep-disordered breathing and a level 2 polysomnogram to confirm OSA presence and severity. To date 28 patients have been assessed for OSA (9M/27F; Age 67±2y; BMI 35.0±1.6kg/m2; BNP 214±64ng/L). All 28 patients (100%) were diagnosed with OSA (AHI≥5 events/h), while 16 (57%) had moderate-severe OSA (AHI≥15 events/h). Average ESS was 7±1, with only 6 patients (21%) identified at risk for sleep-disordered breathing (ESS>9). These preliminary data confirm a very high prevalence of OSA in HFpEF patients when assessed via polysomnography. Furthermore, these patients appear asymptomatic in terms of sleepiness, as measured by the ESS. The nature of the association between OSA and HFpEF and the potential benefit of OSA treatment warrant study. Given that the ESS did not effectively identify OSA risk in HFpEF, alternative screening tools warrant consideration.