Sleep apnea in patients with exacerbated heart failure and overweight

Abstract

Abstract Background Exacerbated heart failure is a condition with a high frequency of hospitalizations and mortality, especially in overweight patients. Screening and treatment for sleep apnea can be helpful in these patients. Purpose To determine the frequency and the phenotypic characteristics and of sleep apnea in patients with overweight and exacerbated heart failure. To assess systolic and diastolic function in patients with obstructive and central sleep apnea. To follow patients for one year and to assess hospitalization and mortality. Methods We conducted a single-centre, prospective cohort study form 120 consecutive patients hospitalized for exacerbation heart failure in the cardiology department. 70 patients meet inclusion criteria – Apnea-Hypopnea index (AHI) > 5, Epworth Sleepiness Scale (ESS) > 6, NTproBNP>900 pg/ml, and Body mass index(BMI) >25. All patients receiving optimal medical treatment. The follow-up period was 1 year. The primary endpoint was death for any reason. Sleep apnea screening was performed with ApneaLinkTM. Echocardiographic assessment of left ventricular ejection fraction (LVEF) and the E/e‘m ratio. Results From 70 with sleep apnea 73% (n=51) has obstructive sleep apnea (OSA) and 27% (n=19) has central sleep apnea (CSA). Detected significant changes in LVEF between the OSA group and CSA group (EF% 49.7±8.5vs43.3±9.6.4;p=0.008). Statistically significant changes there was about E/e’m ratio (E/e’m-17.01±3.7 vs 19.3±2.73; p=0.015) and BMI (BMI-38.2±6.5 vs 32.2±3.6; p<0.001). We found a moderate reverse correlation between the LVEF and the number of central sleep apnea events (r=-0,34;p=0,003). Simple linear regression was used to test if the left ventricular ejection fraction significantly predicted the number of central apnea events. The overall regression was statistically significant (R2 = 0.120, F(1,68) = 9.26, p = .003). It was found that the left ventricular ejection fraction significantly predicted the number of central apnea events (β = -0.06, p = .003). Patients from both groups were followed up regarding first hospitalization for heart failure and mortality over a period of 12 months. First hospitalization in patients with CSA occurs significantly sooner than in patients with OSA. The average number of months without hospitalization for HF in patients with CSA was 6.7 months versus 9.7 months in patients with OSA (Log Rank (Mental-Cox) p=0.012). The OSA group had a median survival of 10.5 months versus 9.3 months in the CSA group (Log Rank (Mental-Cox) p=0.026). Conclusion Sleep apnea is a common comorbidity in patients with exacerbated heart failure and overweight. OSA occurs to a greater extent than CSA. Patients with reduced systolic function are at higher risk of central sleep apneas events. Low LVEF% can be used as a prognostic factor regarding the occurrence of central sleep apnea events. Controlling sleep apnea can reduce patient readmissions and mortality.