Longitudinal changes of obstructive sleep apnea and its impact on cardiovascular outcomes: Results from the Sleep Heart Health Study.

BACKGROUND

Little is known about the longitudinal change in OSA and its impact on cardiovascular outcomes. This study aimed to investigate the association between the OSA changes and cardiovascular outcomes.

METHODS

In the Sleep Heart Health Study (SHHS), participants who underwent two polysomnograms, approximately five years apart, were included. OSA was defined as apnoea-hypopnoea index (AHI) ≥15 events/hour. Clinical characteristics and outcomes were examined overall and by sex. The primary outcome was major adverse cardiovascular and cerebrovascular events (MACCE), including cardiovascular death, heart failure, myocardial infarction, revascularization and stroke.

FINDINGS: A total of 2653 participants (45.9% men) were included. Of them, 364 (19.6%) participants without OSA developed OSA, and 258 (32.6%) participants with OSA reverted to a non-OSA state. The proportion of women with stable AHI was higher than that of men (59.3% vs. 46.0%, p < 0.001). In men, increased risk of MACCE was observed in the non-OSA to OSA group (absolute risk [AR], 35.5%; hazard ratio [HR], 1.52 [95% CI, 1.00-2.30]), OSA to non-OSA group (AR, 42.3%; HR, 1.54 [95% CI, 1.03-2.38]), and stable OSA group (AR, 44.9%; HR, 1.70 [95% CI, 1.20-2.41]), compared with the stable non-OSA group, but not in women. AHI gain was associated with a higher risk of MACCE and mortality in men.

CONCLUSIONS

OSA course showed dynamic changes. Increased AHI was associated with higher cardiovascular risk, and a reduction in AHI in patients with OSA may not signify complete remission of cardiovascular risk, particularly among men. No such association was observed in women.