Embolic Stroke of Undetermined Source- is OSA a causal factor?

Title: Embolic Stroke of Undetermined Source- is OSA a causal factor?
Author(s): S Toland K McEvoy L Stewart A McGowan P Guilfoyle E Dolan L Cormican
Institution: Connolly Hospital, Blanchardstown
Poster: Click to view poster
Category: Sleep
Abstract: Embolic stroke of Undetermined Source (ESUS) is a type of ischaemic stroke defined as a non-lacunar brain infarct without proximal arterial stenosis or cardioembolic sources. ESUS accounts for about 1 in 6 ischemic strokes. Obstructive sleep apnoea, a form of sleep-disordered breathing, is associated with multiple major stroke risk factors including hypertension and atrial fibrillation, but it is also an independent risk factor for stroke.

We conducted a prospective study assessing 11 patients in Connolly Hospital admitted with a diagnosis of ESUS who underwent sleep studies between January and August 2021. All of these patients underwent a full stroke workup prior to their sleep study including CT brain, MRI brain, Echocardiogram, Carotid dopplers, Holter monitor and a full blood panel.

Of the 11 patients, 7 (63.6%) of the patients were female with a median age of 63. All 11 patients (100%) had an AHI (Apnoea-Hypopnoea Index) on their sleep study consistent with Obstructive Sleep Apnoea (OSA). The median AHI observed was 16.5, with 4 patients (36%) in the mild category (AHI 5-15/hour), 4 (36%) in the medium category (AHI 15-30/hour) and 3 (27.2%) falling into the severe category (AHI >30/hour).