Obstructive sleep apnea (OSA) affects roughly 17 percent of U.S. adults and is associated with an increased risk for cardiovascular diseases and overall mortality. Two studies released today in The Journal of the American Medical Association address the topic of OSA, particularly in terms of treatment with continuous positive airway pressure (CPAP) therapy which is known to decrease overall cardiovascular rest.
The first study looks at the ability of CPAP to prevent new-onset hypertension. The findings from the study suggest that when compared with patients without OSA, "untreated OSA is associated with an increased risk for developing new-onset hypertension and that long-term CPAP therapy is associated with a reduction in such risk." Data also suggest that weight gain over a longer period of time does not appear to diminish a protective association of CPAP therapy against development of new-onset hypertension in OSA. "Our observational findings suggest that OSA appears to be a modifiable risk factor for new-onset hypertension," the study authors report.
The second study looked at the effect of CPAP treatment on the incidence of hypertension or cardiovascular events in a cohort of OSA patients without daytime sleepiness. According to the study authors, the benefits of CPAP therapy for all patients with sleep-disordered breathing, regardless of daytime symptoms, is currently unclear. The results from the study indicate there is not a statistically significant reduction in the incidence of hypertension or cardiovascular events in non-sleepy OSA patients using CPAP therapy versus usual care. However, the authors do note that this particular study may have limited ability to detect a significant difference: "A post hoc analysis suggested that CPAP treatment may reduce the incidence of hypertension or cardiovascular events in patients with CPAP adherence of four h/night or longer."