Background: Obstructive sleep apnea (OSA) is a major cause of secondary hypertension.
Moreover, a considerable proportion of patients with essential hypertension have OSA. OSA
also appears to increase the risk for cardiovascular disease and all-cause mortality. Continuous positive
airway pressure (CPAP) treatment substantially reduces daytime somnolence and improves
quality of life in patients with OSA. However, the effects of CPAP treatment on blood pressure
(BP) are questionable. The aim of the present review is to summarize the evidence regarding the
association between OSA with hypertension and the effects of CPAP treatment on BP in patients
with OSA. The severity of OSA directly correlates with the increase in BP. Moreover, patients with
OSA are at increased risk for developing hypertension. However, CPAP treatment does not result in
substantial reductions in BP in unselected patients with OSA with moderate adherence to this
treatment. Nevertheless, these effects are more pronounced in patients with more severe hypertension,
more severe OSA and more importantly, in those who adhere to CPAP treatment.
Conclusion: Therefore, it is essential to improve the adherence to CPAP treatment in order to optimally
manage this important cause of hypertension.