Cross-sectional studies have linked sleep-disordered breathing, like obstructive sleep apnea (OSA), to cardiovascular disease (CVD) including coronary artery disease, congestive heart failure, and stroke. The most frequent assumption is that OSA increases the risk of CVD.
HA Chami et al studied the association of incident cardiovascular disease (iCVD) with worsening of OSA. In this study, the iCVD refers to the number of cardiovascular disease diagnoses over a five year period. The study authors wanted to determine if iCVD causes or worsens OSA. The study was published in the journal Circulation.
The results showed that iCVD was associated with worsening of OSA after adjusting for age, sex, race, site, chagne in body-mass index, cahnge in neck circumference, and difference in percent sleep time spent in teh supine position and with further adjustment for baseline blood pressure, cholesterol, smoking, and change in medication use. The results did not show that iCVD could bring on OSA where it did not previously exist.
The authors concluded that OSA is a risk factor for OSA and also that CVD can potentially worsen (but not cause) OSA. The mechanism is not understood, but it could be related to instability in how we control our breathing while asleep. Cardiac disease could contribute to breathing instability, which could then worsen OSA.
These findings reinforce the complex relationship between heart health and sleep health, and how important it is for cardiac patients to discuss their sleep with their cardiologists and primary care physicians.