Role of Sympathetic Nervous System in the Metabolic Syndrome and Sleep Apnea

This article will review the role of the sympathetic nervous system in the pathogenesis of metabolic syndrome and sleep apnea and the pathophysiological link between these two clinical conditions. Several indices of adrenergic tone have all shown an increase in the different conditions clustering in the metabolic syndrome. The adrenergic overdrive appears to be potentiated in the metabolic syndrome and contributes at the cardiovascular, structural, and functional alterations typical of this condition. Several mechanisms, supporting the hyperadrenergic state in metabolic syndrome, are also present in another pathophysiological condition, such as obstructive sleep apnea, which contributes to determining the increased cardiovascular risk of these patients. The data reviewed herein support the relevance of the sympathetic nervous system in the pathogenesis of the metabolic syndrome and sleep apnea and highlight the importance of the sympathomodulation as a specific aim of therapeutic intervention to reduce the cardiovascular risk and the morbidity of these pathophysiological conditions.