Research
Hot Flashes and Cardiovascular Health: The Association
Women who report frequent or persistent hot flashes and night sweats, together called vasomotor symptoms (VMS), tend to have worse scores on early, subclinical markers of cardiovascular disease, and a higher rate of later cardiovascular events, than women with few or no such symptoms. In the Study of Women's Health Across the Nation (SWAN), persistent frequent VMS were associated with a roughly 77% higher rate of subsequent cardiovascular events. This is an association, not proof that hot flashes cause heart disease. The researchers themselves say the causal nature is unknown. This page summarizes the verified figures and what they do and do not mean.
By the Sweat Explained Editorial Team · Published 2026-07-13 · Last reviewed 2026-07-13 · Educational information, not medical advice.
Key statistics at a glance
HR 1.51
rate of incident CVD events for frequent VMS (≥6 days/2 weeks) at baseline vs infrequent, 95% CI 1.05–2.17 (SWAN, adjusted)
Thurston 2021, JAHA
HR 1.77
rate of incident CVD events for persistently frequent VMS across the transition, 95% CI 1.33–2.35 (SWAN, adjusted)
Thurston 2021, JAHA
231 events
cardiovascular events observed over up to 22 years in 3,083 SWAN women
Thurston 2021, JAHA
~half
of women in the MsHeart study had carotid plaque; more frequent objectively measured VMS tracked with more plaque and thicker carotid walls
Thurston, MsHeart
association
the researchers state any causal link between VMS and cardiovascular health is currently unknown
Thurston 2024 review
What the research actually shows
Over the past decade, work led by the SWAN and MsHeart/MsBrain investigators has repeatedly found that women with more frequent or more persistent hot flashes score worse on early, pre-symptomatic markers of cardiovascular disease. These markers include poorer endothelial function (how well the artery lining relaxes, measured by brachial-artery flow-mediated dilation), greater thickness of the carotid artery wall (carotid intima-media thickness, or IMT), more carotid plaque, and greater calcification in the aorta and coronary arteries.
The pattern also extends to hard outcomes. In SWAN, women who reported frequent vasomotor symptoms, and especially those who reported them persistently across the menopause transition, went on to have more heart attacks, strokes, and other cardiovascular events during long-term follow-up. Crucially, these relationships are associations: the studies show that VMS and cardiovascular risk travel together, not that one causes the other.
Frequent and persistent VMS track with more later CVD events
In SWAN, 3,083 women were followed for up to 22 years, during which 231 cardiovascular events occurred. After adjustment for demographics, medications, and standard CVD risk factors, frequent hot flashes at baseline, and persistent frequent hot flashes over time, were associated with a higher rate of events. Values are hazard ratios (a hazard ratio of 1.0 means no difference; 1.5 means a 50% higher rate).
| Group | Value |
|---|---|
| VMS 1–5 days/2 wks (vs none) | 1.02 (95% CI 0.75–1.39, not statistically significant) |
| Frequent VMS ≥6 days at baseline | 1.51 (95% CI 1.05–2.17) |
| Persistently frequent VMS | 1.77 (95% CI 1.33–2.35) |
Source: Thurston RC, et al., J Am Heart Assoc 2021;10:e017416. Chart is an original rendering of the cited data.
Associations across subclinical cardiovascular markers
Beyond events, several SWAN and MsHeart analyses link VMS to earlier, subclinical measures of vascular health. These are cross-sectional or longitudinal associations, adjusted for standard risk factors and in several cases for sex hormone levels.
Associations reported after adjustment for demographic and cardiovascular risk factors, and in several analyses for endogenous sex hormones. Association is not proof of cause.
Why this is an association, not a proven cause
It is tempting to read these findings as "hot flashes damage your heart," but that is not what the evidence establishes. The SWAN and MsHeart investigators are explicit: as they put it, the precise nature of these relationships, and particularly any causal link between vasomotor symptoms and cardiovascular health, is currently unknown.
Several explanations are plausible and not mutually exclusive. Underlying vascular changes could give rise to both more bothersome hot flashes and higher cardiovascular risk. A third, shared factor (such as autonomic nervous-system function) could drive both. Or the relationship could run in more than one direction. Because these are observational cohort studies, they can establish that the two travel together and rule out some confounders, but they cannot prove which, if anything, causes which.
The bigger midlife picture
This research sits inside a broader shift in how the menopause transition is viewed. A 2020 scientific statement from the American Heart Association describes the menopause transition as a time of accelerating cardiovascular risk, marked by adverse changes in body-fat distribution, lipids and lipoproteins, and vascular structure and function, and identifies midlife as a window for earlier cardiovascular prevention. Vasomotor symptoms are one signal among several that researchers are studying in this context.
For an individual, the practical reading is modest: frequent, persistent hot flashes may be a marker worth noting alongside standard cardiovascular risk factors, not a diagnosis or a reason for alarm. Questions about personal cardiovascular risk, hot-flash burden, and any treatment are best discussed with a clinician who can look at the whole picture.
Methodology and limitations
This page draws on primary SWAN and MsHeart/MsBrain publications (Thurston 2021, J Am Heart Assoc, on incident CVD events; Thurston 2016, Stroke, on VMS trajectories and carotid IMT), a review by the primary investigator summarizing the SWAN and MsHeart/MsBrain program, and the 2020 American Heart Association scientific statement on the menopause transition and CVD risk. Each headline figure was traced to its source and confirmed.
Limitations: these are observational cohort studies. They show associations between vasomotor symptoms and cardiovascular markers or events after statistical adjustment, but they cannot prove that hot flashes cause cardiovascular disease; the investigators state the causal nature is unknown. Hazard ratios come from a specific cohort and set of adjustments and may not transfer to every population. "Frequent" and "persistent" VMS are defined differently across analyses (self-reported ≥6 days in 2 weeks in SWAN; objectively measured in MsHeart). Nothing here is a diagnosis or medical advice.
Frequently asked questions
- Do hot flashes cause heart disease?
- The research does not show that. It shows that frequent and persistent hot flashes are associated with worse early cardiovascular markers and more later cardiovascular events. The SWAN and MsHeart investigators state that any causal link is currently unknown. The two travel together, but cause has not been proven.
- How much higher was the cardiovascular event rate in SWAN?
- After adjustment, women with frequent hot flashes (6+ days in 2 weeks) at baseline had about a 51% higher rate of cardiovascular events (hazard ratio 1.51, 95% CI 1.05–2.17). Those with persistently frequent hot flashes had about a 77% higher rate (HR 1.77, 95% CI 1.33–2.35), across 231 events over up to 22 years.
- Do occasional hot flashes carry the same association?
- In the SWAN event analysis, women reporting hot flashes on only 1–5 days in 2 weeks did not have a statistically significant increase (HR 1.02, 95% CI 0.75–1.39). The associations were seen mainly with frequent and persistent symptoms.
- What are 'subclinical' cardiovascular markers?
- They are early, measurable signs of vascular change before any symptoms or events: for example, how well the artery lining relaxes (endothelial function), the thickness of the carotid artery wall, the presence of carotid plaque, and calcium buildup in the aorta or coronary arteries. Frequent VMS have been associated with worse scores on these.
- Should frequent hot flashes change how I think about my heart health?
- They may be worth mentioning to a clinician alongside standard risk factors like blood pressure, cholesterol, and family history, not as a diagnosis or cause for alarm. A clinician can assess overall cardiovascular risk and discuss any hot-flash treatment in that fuller context.
Sources
Primary peer-reviewed studies and official sources first, then reviews and institutional framing (secondary).
- Thurston RC, Aslanidou Vlachos HE, Derby CA, et al. Menopausal Vasomotor Symptoms and Risk of Incident Cardiovascular Disease Events in SWAN. J Am Heart Assoc. 2021;10(3):e017416. HR 1.51 (frequent), 1.77 (persistent); 231 events, N=3,083. PubMed
- Thurston RC, El Khoudary SR, Tepper PG, et al. Trajectories of Vasomotor Symptoms and Carotid Intima Media Thickness in the Study of Women's Health Across the Nation. Stroke. 2016;47(1):12–17. PubMed
- El Khoudary SR, Aggarwal B, Beckie TM, et al. Menopause Transition and Cardiovascular Disease Risk: Implications for Timing of Early Prevention. A Scientific Statement From the American Heart Association. Circulation. 2020;142(25):e506–e532. PubMed
- Thurston RC. Vasomotor symptoms and cardiovascular health: findings from the SWAN and the MsHeart/MsBrain studies. Review summarizing endothelial function, carotid IMT and plaque, calcification, and event findings; states causal nature is unknown. (secondary) Full text
How to cite this page
Sweat Explained. Hot Flashes and Cardiovascular Health: The Association. Published 2026-07-13; last reviewed 2026-07-13. Available at: https://sweatexplained.com/research/hot-flashes-and-cardiovascular-health-research
Please cite the original studies for the underlying figures. Journalists are welcome to link to this page; the charts are original renderings of the cited data.