Association of sleep apnea with clinically silent microvascular brain tissue changes in acute cerebral ischemia

Abstract

The aim of this study was to determine the importance of sleep apnea in relation to clinically silent microvascular brain tissue changes in patients with acute cerebral ischemia. Patients with acute cerebral ischemia prospectively underwent nocturnal respiratory polygraphy within 5 days from symptom-onset. Sleep apnea was defined as apnea-hypopnea-index (AHI) ≥5/h. Experienced readers blinded to clinical and sleep-related data reviewed brain computed tomography and magnetic resonance imaging scans for leukoaraiosis and chronic lacunar infarctions. Ischemic lesions were considered clinically silent when patients did not recall associated stroke-like symptoms. Functional outcome was assessed with modified Rankin Scale at discharge, 6 and 12 months. Fifty-one of 56 (91 %) patients had sleep apnea of any degree. Patients with moderate-tosevere leukoaraiosis (Wahlund score ≥5) were found to have higher mean AHI than those with none or mild leukoaraiosis (34.4 vs. 12.8/h, p < 0.001). Moderate-to-severe sleep apnea (AHI >15/h) was found to be an independent predictor of moderate-to-severe leukoaraiosis (adjusted OR 6.03, 95 % CI 1.76-20.6, p = 0.0042) and of moderate-to-severe leukoaraiosis associated with clinically silent chronic lacunar infarctions (adjusted OR 10.5, 95 % CI 2.19-50.6, p = 0.003). The higher the Wahlund score and the AHI, the more likely unfavorable functional outcome resulted over time (p = 0.0373). In acute cerebral ischemia, sleep apnea is associated with clinically silent microvascular brain tissue changes and may negatively influence functional outcome. Routine sleep apnea screening and further investigation of possible long-term effects of non-invasive ventilatory treatment of sleep apnea appear warranted in this at-risk population.

Pathological Effects of Obstructive Apneas During the Sleep Cycle in an Animal Model of Cerebral Small Vessel Disease

“…Given that this cascade has similarities to the risk factors associated with CSVD (12;13;17;29), we tested the hypothesis that apneas during the sleep cycle exacerbate hypertension and accelerate pathological changes that occur with CVSD. The specific neuropathological changes included neuroinflammation, BBB integrity, white matter integrity, and cognitive function.…”

Obstructive sleep apnea and retinal microvascular characteristics: a brief review

“…Cerebral small vessel disease was represented by white matter changes or lacunar infarcts in brain magnetic resonance imaging (MRI) or computed tomography studies. There were no consistent results for a positive relationship between moderate to severe OSA classified by AHI or RDI and cerebral small vessel disease [30][31][32][33][34][35][36][37][38]. The results were also uncertain for the association of intermittent hypoxemia with cerebral small vessel disease [31].…”

“…Obstructive sleep apnea and retinal microvascular characteristics: a brief review Review Gen-Min Lin were performed [30][31][32][33][34][35][36][37][38]. Cerebral small vessel disease was represented by white matter changes or lacunar infarcts in brain magnetic resonance imaging (MRI) or computed tomography studies.…”

An update in sleep neurology: the latest bedtime stories

“…Those who deal with inpatients acutely and particularly those who see anyone with cerebrovascular disease need to again remember the bidirectional relationship between large and small vessel stroke and sleep-related breathing problems. Small vessel disease and cardioembolic disease are most strongly associated with coexistent sleep apnoea [14]. Sleep apnoea is increasingly recognised as an independent risk factor for stroke and on the stroke unit itself it can contribute to a worse outcome and increased mortality.…”