Obstructive sleep apnoea and atrial fibrillation: a key omission in guidelines
The National Institute for Health and Care Excellence (NICE) guidelines for atrial fibrillation (AF) and obstructive sleep apnoea (OSA) lack recommendations for the subset of patients with both conditions. There is growing evidence of a bidirectional association between AF and OSA, which we believe is not highlighted in current NICE guidelines. The ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation) cohort study highlighted that about one in five patients with AF also had OSA.1 For this group of patients, screening, diagnosis and treatment are crucial.
AF is the most common cardiac arrhythmia in clinical practice,2 while OSA had an estimated UK prevalence of 1.5 million adults in 2014.3 With the obesity epidemic and demographic changes with an ageing population, the prevalence of both conditions is likely to increase with OSA and AF sharing common independent risk factors, such as age, obesity, smoking status and alcohol intake.4-7
Although the pathophysiological processes for the associated interplay between AF and OSA are complex, and continue to be debated by the scientific community, studies have demonstrated increased prevalence of AF in OSA patients and vice versa.8,9 The Sleep Heart study, comprising of participants with sleep-disordered breathing, found that those with severe OSA had a four-fold risk of AF when compared with those without OSA (adjusted odds ratio [OR] 4.02, 95% confidence interval [CI] 1.03 to 15.74).8 The British Lung Foundation notes that OSA is underdiagnosed,3 and, thus, clinicians could be missing the opportunity for diagnosis by not screening for OSA in AF patients and vice versa.
Patients diagnosed with concurrent AF and OSA without appropriate continuous positive airway pressure (CPAP) therapy may also respond poorly to pharmacological and non-pharmacological treatment of AF.10‑13 The risk of recurrence of AF after cardioversion or ablation was found to be higher in patients with untreated OSA,10 while, in those who had treatment, the risk was similar to patients without OSA.11,12
OSA is an important, yet overlooked, risk factor in AF. At present, there is no reference to the association between OSA and AF in the NICE guidelines for AF and the only reference to this subset is within the OSA guidelines, whereby NICE suggests clinicians assess “any associated conditions”. In contrast, the American Heart Association, American College of Cardiology and Heart Rhythm Society guidelines highlight OSA as a risk factor in AF and recommends a sleep study for AF patients with suspected OSA.14 We would recommend that clinicians screen and test for OSA in AF patients and request that guidelines reconsider including OSA screening as a part of standard practice in AF patients.