Palpitations, breathlessness or chest pain are sometimes dismissed around the time of the menopause as stress or ‘just part of the process’. In this advance extract from De overgang: Een nieuwe fase, the new book from the Foundation for Biosciences and Society, cardiologist Janneke Wittekoek describes why the years around the menopause represent a crucial turning point for the heart and blood vessels.
Cardiovascular disease is the leading cause of death in women worldwide. The risk of cardiovascular disease generally increases with age, but the menopause plays an additional role. The years around the menopause represent a crucial turning point for the female heart.
The menopause as a turning point
Oestrogen has a protective effect on blood vessels. As levels of the hormone decline during the years around the menopause, that protection diminishes. Blood vessels become stiffer and more susceptible to dysregulation. This does not make the menopause the starting point of disease, but it does act as an accelerator of processes that have often been under way for some time, such as problems with blood pressure or lipid metabolism.
In women, cardiovascular problems often begin more subtly than in men. The blood vessels gradually start to function less well. They relax less easily, respond more strongly to stimuli and can even go into temporary spasm. We call these functional vascular problems. There is no clear blockage at this stage, but blood flow to the heart is nonetheless disrupted. It is precisely in this phase that symptoms often first appear, such as chest pain, breathlessness or extreme fatigue. In men, the risk of cardiovascular disease develops differently. In them, we more often see the classic picture of a narrowing in a coronary artery – a ‘blocked’ vessel on the outer surface of the heart. We call this obstructive vascular disease. This pattern also occurs in women, but typically arises later in the disease process.
Physical changes
The inner lining of blood vessels
The inner lining of the blood vessels (the endothelium) plays an essential role in regulating vascular function. It enables blood vessels to adapt to changes in the oxygen and nutritional demands of organs and tissues. Oestrogen assists in this process. It allows blood vessels to relax more readily and protects them against damage. After the menopause, this protection is lost. The blood vessels become stiffer and respond less effectively. Sometimes they even contract briefly. This occurs particularly in the smallest blood vessels of the heart – and those are precisely the ones that are most difficult to examine.
Women often describe a pressing or constricting sensation in the chest, pain between the shoulder blades, a feeling that their bra is too tight, difficulty breathing deeply or a sense of not being able to take a full breath. These symptoms are not always accompanied by visible narrowing of the coronary arteries. As a result, they are regularly missed or misinterpreted.
Blood pressure
Many women develop higher blood pressure after the menopause. Resistance in the now-stiffer vessels increases, meaning the heart has to work harder to pump blood around the body. The body also responds differently to hormones and stress.
Cholesterol
Although cholesterol levels can change gradually as we age, in women there is often a marked acceleration around the menopause. Oestrogen influences the way in which the liver processes cholesterol and helps to remove LDL cholesterol from the blood. When oestrogen levels fall, LDL cholesterol often rises and the number of harmful LDL particles can also increase. At the same time, the protective effect of HDL cholesterol diminishes. This increases the likelihood that cholesterol will accumulate in the vessel wall and that atherosclerosis will develop.
Fat distribution
After the menopause, the way in which the body stores fat also changes. Abdominal fat often increases, and this has a direct impact on health and on the risk of cardiovascular disease. It can lead to greater inflammatory responses, reduced insulin sensitivity and higher cholesterol.
Head, heart and hormones belong together
The heart does not function in isolation. There is a strong connection between the heart, the brain and various hormones. Together they form a system that is constantly ‘in conversation’ with itself. When hormones change, so does the way in which the body responds to stress and the way in which blood vessels function. The reverse is also true: stress can have a direct effect on the heart and blood vessels.
The brain sends signals to the heart and blood vessels via the nervous system. During stress, for example, the heart rate rises and blood vessels constrict. This is a normal response. But when stress is frequent or prolonged, this system remains, as it were, switched ‘on’. Oestrogen helps to keep this system in balance. It allows blood vessels to relax more easily and dampens the body’s stress response.
After the menopause, this brake is partly removed. The body responds more quickly and more strongly to stimuli such as stress, emotions or exertion. As a result, blood vessels can go into spasm more readily, and a shortage of oxygen in the heart muscle can develop more easily – even in the absence of any narrowing.
This explains why symptoms such as those mentioned earlier (pain or pressure in the chest, pain between the shoulder blades, and so on) can sometimes be difficult to place in women. These symptoms often vary in intensity and occur not only during exertion but also in response to stress, emotions or even at rest. Sometimes the symptoms seem inexplicable – but they are not. They simply do not always fit the classic picture of a blocked coronary artery. The problem then lies not in the lumen of the blood vessel, but in the function and regulation of the blood vessels themselves.
The female heart across a lifetime
The risk of cardiovascular disease does not arise suddenly. It builds up, step by step, over the years. Female-specific factors from earlier in life can increase the risk of cardiovascular disease in later years. Risk factors vary considerably from person to person. Some examples:
– migraine
– recurrent miscarriages
– high blood pressure during pregnancy
– pre-eclampsia or HELLP syndrome
– endometriosis and adenomyosis
These are not isolated problems. They may be indicators that the blood vessels are more susceptible. Around the menopause, this susceptibility can become more apparent.
What can you do yourself?
Fortunately, an elevated cardiovascular risk after the menopause does not mean that cardiovascular disease is inevitable. This stage of life in particular offers considerable scope for benefit through timely recognition and prevention. A good first step is knowing your key risk factors: blood pressure, cholesterol, blood sugar, weight and waist circumference. In addition, always discuss menopausal symptoms, palpitations, shortness of breath, chest pain or a decline in fitness with your doctor – especially if these are new or worsening.
Where there are indications of an elevated risk, further investigations can be carried out, such as blood tests, an exercise stress test, a CT scan of the coronary arteries or specialist assessment of the function of the small blood vessels of the heart.
Treatment depends on the cause of the symptoms and the individual risk profile. Sometimes lifestyle measures are sufficient – such as increased physical activity, a healthy diet, stopping smoking, adequate sleep and stress reduction. In other cases, treatment of high blood pressure, elevated cholesterol or diabetes may be necessary. In some women with menopausal symptoms, hormone replacement therapy (HRT) may form part of the treatment, provided it is carefully tailored to the individual’s personal situation (see box: ‘Hormone replacement therapy – many misconceptions’).
The most important message is that symptoms should not be dismissed as ‘part of the menopause’. The menopause is an important moment to take a fresh look at cardiovascular health and, where necessary, to intervene in good time. The menopause is not a disease, but it is a significant cardiovascular turning point.
Hormone replacement therapy – many misconceptions
Hormone replacement therapy (HRT) long had a poor reputation with regard to cardiovascular disease. This was due largely to the publication of the Women's Health Initiative study in 2002. In this large American trial, HRT was associated with an increased risk of cardiovascular disease and stroke, among other conditions. The findings caused widespread concern about the safety of HRT worldwide.
Later, however, it emerged that the women studied had an average age of 63 and had often only begun HRT many years after the menopause. Many of them also already had risk factors for cardiovascular disease. The study population therefore differed considerably from the women who start HRT in everyday clinical practice because of menopausal symptoms, usually around the time of the menopause.
We now know that timing is of great importance. When HRT is started around the menopause – before the age of 60, or within ten years of the last menstrual period – the cardiovascular risk appears to be low for most healthy women. Some studies even suggest that early treatment may have beneficial effects on the blood vessels. Oestrogen supports several processes that are important for healthy vascular function.
That does not mean HRT is suitable for every woman. It is not a straightforward choice between taking or not taking HRT, but a matter of tailoring treatment to the individual. Age, time since the menopause, symptoms, personal preferences, and cardiovascular risk profile all play a role.
For some women, HRT is inadvisable or requires extra caution. Where the heart and blood vessels are concerned, factors such as a previous venous thrombosis or pulmonary embolism, a recent stroke, or established cardiovascular disease must be taken into account. In such situations, the benefits and risks must be weighed carefully.
Not just a women's complaint
De overgang: Een nieuwe fase addresses a phase of life that has long been brushed aside as a private inconvenience, even though its consequences can affect the heart, brain, bones, sex life, work, and care. Edited by Monique Brood-van Zanten, Dorenda van Dijken, and Susana Chuva de Sousa Lopes, the book brings together specialists and personal accounts to map out what changes hormonally, physically, and socially around the menopause. The book is at times explicitly educational in tone, but that is precisely what makes it useful: it corrects persistent misconceptions about HRT, the female heart, sexuality, and 'hormonal balance'. In doing so, it makes clear that the menopause is not some vague women's complaint, but a phase of life with biological consequences that are still too often underestimated. (SvS)