Chronic intermittent hypoxia and hypertension: a review of systemic inflammation and Chinese medicine.

Obstructive sleep apnea syndrome (OSAS) and hypertension commonly coexist. Clinical studies indicate that OSAS plays a key role in increasing the risk of prevalent hypertension. Chronic intermittent hypoxia (CIH) is the core pathological mechanism of OSAS, and has a close relationship with systemic inflammation. Growing evidence shows that CIH and hypertension are strongly related, involving markers or pathways indicative of systemic inflammation, such as high-sensitivity C-reactive protein (hs-CRP), interleukin-6, nuclear factor-kappa B, tumor necrosis factor-α, interleukin-8 and p38 mitogen-activated protein kinase (MAPK)-dependent pathways. Oxidative stress also plays an important role in this process, including in the activation of polymorphonuclear neutrophils. However, the pathophysiological and clinical significance of systemic inflammation in CIH and hypertension is not proven. This review article highlights the relationship between CIH and hypertension through systemic inflammation and the current interventions available in Chinese medicine, to offer a background for the future treatment of OSAS-related hypertension with integrative medicine.