ABSTRACT
Background Sleep-disordered breathing (SDB) has a potential association with the pathogenesis of congestive heart failure (CHF). We assessed the prevalence and patterns of obstructive sleep apnea (OSA) in patients presenting with CHF. Method This was a prospective, observational, all-comers study of consecutive 77 confirmed cases of CHF. All these patients were clinically assessed and evaluated for OSA with sleep study after routine blood testing, electrocardiogram (ECG), chest X-ray, and echocardiography. Results Of 77 patients with CHF 38 (49.4%) had apnea-hypopnea index (AHI) <5 while 39 (50.6%) had AHI >5. Of these 39, 37 (94.8%) patients showed the clinical features of OSA. The majority (64.9%) of them were males. The majority of OSA (64.9%) had coronary artery disease (CAD) (p<0.05) as the etiology of CHF, followed by dilated cardiomyopathy (32.4%) and valvular heart disease (2.7%). The prevalence of OSA was higher amongst New York Heart Association (NYHA) class 2 (51.4%) as compared to NYHA class 3 (37.8%) and NYHA class 4 (10.8%). There were 12 (32.8%) patients, each having OSA with a heart rate between 71 and 80 bpm and 81 and 90 bpm. Twenty-two (59.5%) had systolic blood pressure (BP) more than 120 mmHg and 20 (54.1%) had diastolic BP more than 80 mmHg. The majority (64.9%) patients had the lowest O2 saturation between 80% and 90%. A significantly large number of patients (62.2%) had ejection fraction 21%-30% (p<0.05). The majority (62.16%) of patients with OSA had AHI between 5 and 15. With 5-15 AHI, 20 (87%) patients with OSA had a snoring, tiredness, observed apnea, high BP, BMI, age, neck circumference, and male gender (STOP-Bang) score between 3 and 7 with AHI 5-15 (p<0.05). Conclusions In our cohort, the prevalence of OSA in CHF was 50.6%. Predictors of OSA in CHF were left ventricular ejection fraction (LVEF) 20%-30% and NYHA class 2. The majority had AHI between 5 and 15. Sleep apnea screening should be routinely implemented in the evaluation and follow-up of heart failure patients.
