Hot flushes, heart and brain health – an emerging association

Hot flushes are more than an inconvenience – associations with heart and brain health are now emerging.

For a long time, hot flushes and night sweats were seen mainly as a quality-of-life issue. They can certainly disrupt sleep, cause embarrassment, and make day-to-day life difficult. But in recent years, researchers have been asking whether vasomotor symptoms (VMS) might also be a signal of something more — whether they tell us about a woman’s risk of cardiovascular disease or changes in brain health. The evidence is still evolving, but the message is clear enough to take seriously: persistent or frequent flushes are not just uncomfortable, they may also be a red flag for future health risks.

In cardiovascular research, studies such as the SWAN Heart cohort in the United States have found that women who experience frequent hot flushes across the menopause transition are more likely to show early signs of heart and blood vessel disease. These women had greater coronary artery calcification and poorer endothelial function — in other words, changes in the blood vessels that are known to predict cardiovascular events. Even day-to-day blood pressure monitoring shows that flushes can coincide with higher readings, and while those rises may be small, sustained differences over years add up. It is important to be clear: no study has yet shown that a hot flush directly causes a heart attack. Rather, they seem to travel together, which makes hot flushes a useful clinical cue to check other risks carefully.

When it comes to the brain, a similar story is unfolding. Researchers who measure flushes with physiologic monitors — rather than just self-report — have shown that women with more flushes at night tend to have more white-matter hyperintensities on MRI scans. These are small changes in the brain’s wiring that are associated with later cognitive decline. Laboratory work has also shown that on days when flushes are frequent, verbal memory and attention can be subtly worse. None of this proves that hot flushes cause dementia, but it does suggest that women with heavy symptom burdens deserve careful attention to brain as well as heart health.

Some women are particularly vulnerable. Those who go through early or surgical menopause, without oestrogen replacement, face higher long-term cardiovascular and cognitive risks. Carriers of the APOE ε4 gene variant — the most common genetic risk factor for Alzheimer’s disease — also have higher baseline risk. Intriguingly, some observational studies suggest that APOE ε4 carriers who start menopausal hormone therapy (MHT) earlier may perform better on memory tests, but this remains an area of research rather than clinical guidance. It would not be appropriate to recommend genetic testing or to prescribe MHT solely on this basis, but it is one example of how personalised risk may matter in the future.

For now, the more important message is that many of the key risks are modifiable.

Every woman with significant VMS deserves a proper cardiovascular check-up — in Australia, that means a Heart Health Check with calculation of five-year risk using the Australian CVD Risk Calculator, and tailored advice about blood pressure, lipids and diabetes screening. These checks should also consider history of pregnancy complications such as pre-eclampsia or gestational diabetes, which add to lifetime risk. Lifestyle changes still do much of the heavy lifting: regular physical activity, a plant-rich Mediterranean-style diet, adequate sleep, limiting alcohol, and quitting smoking or vaping if relevant. These strategies reduce cardiovascular and dementia risk (and often improve the severity of hot flushes themselves). Screening for sleep apnoea and mood problems is also worthwhile, as both can worsen symptoms and overall cardiometabolic risk.

On the treatment front, MHT remains the most effective option for bothersome hot flushes and night sweats. For women under 60 or within about ten years of menopause, the benefits usually outweigh the risks when therapy is tailored to the individual. For women who are older, or further from menopause, MHT is not automatically ruled out, but it requires more careful consideration. At these ages, risks related to blood clots, stroke, and dementia appear to be higher, and decisions should be made case by case, with attention to personal history and preferences. Several non-hormonal medications, including SSRIs, SNRIs, gabapentin, clonidine, and the newer neurokinin-3 receptor antagonist fezolinetant (approved in Australia in 2024), can all reduce hot flushes. The choice depends on other medical conditions and what each woman feels comfortable with.

Where the science is strong is in showing that hot flushes line up with changes in the heart and brain. Where the science is still thin is understanding the nature of that relationship (is it correlation, causation or a common mechanism underlying both), in proving whether treating the flushes themselves reduces those long-term risks and furthermore, if using hormonal or non-hormonal treatments makes any difference. We do not yet know the threshold at which flush frequency becomes dangerous, nor whether all women are equally affected. Genes such as APOE probably play a role, but they are not the whole story.

So, if you are experiencing frequent or persistent hot flushes, the safest path is not to worry, but to act. Check your personal risk, seek information about all treatment options and focus on your healthiest self across diet, exercise, and medications. That way, you are not only improving your quality of life now, but also protecting your heart and brain health in the decades ahead.

References

1. El Khoudary SR, et al. Vasomotor Symptoms and Cardiovascular Events in the Study of Women’s Health Across the Nation Heart Study. Journal of the American Heart Association. 2021.

2. Thurston RC, et al. Hot Flashes and Subclinical Cardiovascular Disease: Findings from the SWAN Heart Study. Circulation. 2008.

3. Daube JR, et al. Objective Hot Flashes Are Associated With White Matter Hyperintensities in Midlife Women. Neurology. 2022.

4. Maki PM, et al. Physiologic Hot Flashes Are Associated With Poorer Verbal Memory Performance. Menopause. 2008.

5. The North American Menopause Society (NAMS). The 2022 Hormone Therapy Position Statement of The North American Menopause Society. Menopause. 2022.

6. Saleh RN, et al. APOE ε4 Genotype, Menopausal Hormone Therapy, and Cognitive Performance in Midlife Women: EPAD Cohort Findings. Alzheimer’s Research & Therapy. 2023.

7. National Heart Foundation of Australia and Australian Chronic Disease Prevention Alliance. Australian Guideline for Assessing and Managing Cardiovascular Disease Risk. Medical Journal of Australia. 2023.