As many people suffer from milder forms of sleep apnea, they may not take warnings about the dangers of untreated apnea as seriously as those with more severe sleep apnea. These people are partially justified, as severe obstructive sleep apnea (OSA) sometimes causes more issues than milder forms. However, there has been debate about whether even mild sleep apnea can have a negative effect on blood pressure. Recently, a study set out to investigate just that.
In this study, the investigation team wanted to know whether sleep apnea treatment lowers the blood pressure of those with mild OSA as it does of those with more severe forms of apnea. This study was a meta-analysis, meaning the results from many studies were combined to make one ultra-study. These types of analyses are beneficial because they provide a sample size that is much, much larger than usual. In this case, 968 subjects were used. Blood pressure was compared before and after the initiation of OSA treatment in this sample. Subjects being treated with PAP devices were compared with control groups, whose “treatment” included sham (fake) CPAP and placebo pills.
Results found an overall decrease in blood pressure in the subjects who had undergone real OSA treatment. Results also showed that subjects with uncontrolled hypertension (defined as 140/90 before treatment) had the greatest reduction in blood pressure. Amazingly, when controlling for OSA severity, this decrease in blood pressure remained, suggesting that the relationship between the decrease in blood pressure and PAP treatment is independent of apnea severity1.
The large population available for analysis in this study allows researchers to take many health factors into consideration. For example, this research team was able to control for obesity, which is often itself associated with both OSA and high blood pressure, and they were also able to control for sleep apnea severity. In doing this, they are able to create a group that reflects a “normal” population of subjects with sleep apnea. This study makes a great case for sleep apnea treatment, even in those with milder forms of sleep apnea. The proof is in the PAP – get treated and stick with it!
1. Online pre-publication: Journal of Clinical Sleep Medicine: Blood Pressure Improvement with Continuous Positive Airway Pressure is Independent of Obstructive Sleep Apnea Severity