OSA course showed dynamic changes, and increased AHI was associated with higher cardiovascular risk, while a reduction in AHI in patients with OSA may not signify complete remission of cardiovascular risk, particularly among men.
Key Findings
Results
A substantial proportion of participants experienced changes in OSA status over approximately five years, with new onset and reversion both occurring.
Total of 2653 participants were included, 45.9% men.
364 (19.6%) participants without OSA at baseline developed OSA by the second polysomnogram.
258 (32.6%) participants with OSA at baseline reverted to a non-OSA state.
OSA was defined as apnoea-hypopnoea index (AHI) ≥15 events/hour.
The two polysomnograms were performed approximately five years apart.
Results
Women were more likely to have stable AHI over time compared to men.
The proportion of women with stable AHI was higher than that of men (59.3% vs. 46.0%, p < 0.001).
This sex difference in OSA trajectory stability was statistically significant.
Results
In men, new-onset OSA (non-OSA to OSA group) was associated with significantly increased risk of MACCE compared to stable non-OSA.
Absolute risk (AR) of MACCE in the non-OSA to OSA group was 35.5%.
Hazard ratio was 1.52 (95% CI, 1.00–2.30) compared with the stable non-OSA group.
MACCE included cardiovascular death, heart failure, myocardial infarction, revascularization, and stroke.
Results
In men, reversion from OSA to non-OSA status was still associated with significantly elevated MACCE risk compared to stable non-OSA.
AR of MACCE in the OSA to non-OSA group was 42.3%.
Hazard ratio was 1.54 (95% CI, 1.03–2.38) compared with the stable non-OSA group.
This finding suggests that reduction in AHI does not signify complete remission of cardiovascular risk in men.
Results
In men, persistent (stable) OSA was associated with the highest MACCE risk among the OSA trajectory groups.
AR of MACCE in the stable OSA group was 44.9%.
Hazard ratio was 1.70 (95% CI, 1.20–2.41) compared with the stable non-OSA group.
This was the highest hazard ratio among the three at-risk trajectory groups in men.
Results
AHI gain over time was associated with higher risk of MACCE and mortality specifically in men.
AHI gain (increase in AHI between the two polysomnograms) was analyzed as a continuous or categorical exposure.
The association between AHI gain and adverse outcomes was observed for both MACCE and mortality outcomes.
This association was specific to men and was not observed in women.
Results
No significant association between OSA trajectory groups and MACCE risk was observed in women.
Unlike men, none of the OSA change groups (non-OSA to OSA, OSA to non-OSA, or stable OSA) showed a statistically significant increase in MACCE risk compared to stable non-OSA in women.
The sex-specific analyses were pre-specified given clinical characteristics and outcomes were examined overall and by sex.
This sex difference was a key conclusion of the study.
What This Means
This research used data from the Sleep Heart Health Study to examine how obstructive sleep apnea (OSA) — a condition where breathing repeatedly stops during sleep — changes over time and how those changes affect heart health. Among 2,653 adults who had their sleep monitored twice about five years apart, roughly one in five people who initially did not have OSA developed it, while about one in three people who had OSA no longer met the criteria at the second assessment. Women were more likely than men to have stable sleep apnea status over time.
The study found important differences by sex in how OSA changes relate to heart and stroke outcomes (collectively called MACCE — major adverse cardiovascular and cerebrovascular events). In men, having new-onset OSA, persistent OSA, or even OSA that apparently resolved were all linked to meaningfully higher risks of serious cardiovascular events compared to men who never had OSA. The group whose OSA resolved still had a 54% higher relative risk than those who never had OSA, suggesting that past OSA leaves a lasting cardiovascular impact in men. Worsening sleep apnea scores over time were also tied to higher cardiovascular and mortality risk in men. Notably, none of these associations were found in women.
This research suggests that OSA is not a static condition — it can develop, persist, or improve over a few years — and that in men, even apparent improvement in OSA may not eliminate the elevated cardiovascular risk that comes with having had the condition. The lack of similar findings in women raises questions about whether OSA affects cardiovascular health differently by sex, which may have implications for how sleep apnea monitoring and treatment are approached in clinical practice.
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Wenlong Zhao, Jiaqi Du, Yixiang Liu, Yun Zhou, Zekun Zhang, Siyi Li, et al.. (2026). Longitudinal changes of obstructive sleep apnea and its impact on cardiovascular outcomes: Results from the Sleep Heart Health Study.. Pulmonology. https://doi.org/10.1080/25310429.2026.2640670