Sleep apnea and pulmonary hypertension: A riddle waiting to be solved

Obstructive sleep apnea (OSA) is an under-recognized yet highly prevalent disease that has major implications to cardiovascular health. Pulmonary hypertension (pH) is less common but none the less a fatal condition. The association of OSA and PH is a known but not well understood phenomenon. Furthermore, the relationship appears to be bi-directional with limited understanding of the mechanism(s) driving the processes. PH in OSA has real time consequences as it has been shown to increase mortality. Limited data suggests that treatment with continuous positive pressure therapy may be beneficial and reduce pulmonary pressure. In this review, we discuss current data on prevalence of PH in OSA and vice versa. We also explore the pathophysiology of this relationship and a proposed mechanism for their connection. Finally, we address the treatment of OSA with CPAP and its impact on pulmonary pressures. Gaps in knowledge and future research potential are illustrated and discoursed.