Sleep apnea and white matter disease in hypertensive patients: a case series

Obstructive sleep apnea (OSA) is associated with hypertension (HTN) and cardiovascular disease. Transient episodes of hypoxia, hypercapnia, and blood pressure elevation during OSA may lead to neural damage and subsequently white matter disease (WMD). As WMD is usually the result of chronic small vessel ischemia, a relationship between OSA and cerebrovascular disease may exist. This case series aimed to establish a relationship between OSA and WMD. Sixty-two patients without cerebrovascular disease who had both a polysomnogram and brain magnetic resonance imaging were identified. All patients carried the diagnosis of HTN. WMD was evaluated using the age-related white matter changes scale. Although half of the study population had WMD on magnetic resonance imaging, no association was found between WMD with severity of OSA (P=0.9). Our results are limited by the small sample size and by coexistent HTN in all patients. Further studies are needed to elucidate the relationship between OSA and WMD, especially among nonhypertensive patients. Future research should also address if OSA treatment has any effect on WMD.