As documented in our previous post (Menopause and the Metabolic Pathway), menopause has been linked to increased risk of cardiovascular disease (CVD). Women die more of strokes and other CVD conditions than men and it is important to establish ways to minimise risk. Rebecca Thurston and her group have been looking at the relationship with CVD further to see if experience of vasomotor symptoms (VMS) impacted risk.
More than 70% of women experience VMS during transition and 30 % experience severe or frequent symptoms which can last for 7-10 years or longer. Although VMS symptoms don’t always occur at the same time in women, they can be extremely bothersome when they do. Literature has also shown that menopause transition has been seen to occur directly before onset of cardiovascular disease.
So the first question is, are VMS associated with adverse CVD risk factors such as blood pressure, lipids, insulin resistance and inflammation? The WHI study points to VMS among older women leading to a higher number of CVD events. However it should be noted that highly symptomatic women were left out of this study. The HERS study has also suggested that women with baseline VMS have a higher CVD risk with MHT use.
So does estrogen play a part in the VMS associated CVD risk? Data suggests it doesn’t, so when risk factors and estradiol are controlled what is the result? Data from the SWAN and the SWAN Heart studies measured flow mediated dilation which is a marker of endothelial dysfunction and IMT (thickness of intimal and medial layers of artery). Results show the more days women reported VMS the higher their IMT. Bechlioulis et al. also showed that severe hot flushes resulted in poor FMT whilst Ozkaya et al. demonstrated higher IMT in women with increased VMS.
This data suggested VMS might be associated with poor cardiovascular health. However there are some key limitations; patients were asked to report VMS weeks after they had occurred so memory bias may have been introduced into data reported. Thurston et al. 2016 also showed that increased VMS was directly linked to increase in IMT in a very dose-dependent relationship. Whilst more recent data from the same group demonstrated in younger women with VMS that the more VMS they experience the lower their FMT, they also presented results showing that early onset led to higher VMS and IMT with early VMS leading to low FMT and higher CVD mortality risk later in life, suggesting VMS has an impact on CVD risk even when risk factors and estrogen are controlled.
Research by Rebecca’s group shows that VMS starts earlier and lasts longer than initially thought and maybe a midlife marker of CVD risk. More research needs to be done to elucidate underlying mechanism and the impact of age and time. For now the question of whether treating VMS will impact vascular health remains unanswered….
We look forward to hearing from Rebecca’s group when they have an update on the answer!