Menopause is a natural biological process that marks the end of a woman’s reproductive years, typically between 45 and 55. As women approach or experience menopause, common “change of life” concerns include hot flushes, sweats and mood swings, brain fog and fatigue.

But many women may not be aware of the long-term effects of menopause on the heart and blood vessels that make up the cardiovascular system. Heart disease accounts for 35% of deaths in women each year – more than all cancers combined.

What should women – and their doctors – know about these risks?

Hormones protect hearts – until they don’t

As early as 1976, the Framingham Heart Study reported more than twice the rates of cardiovascular events in postmenopausal than pre-menopausal women of the same age. Early menopause (younger than age 40) also increases heart risk.

Before menopause, women tend to be protected by their circulating hormones: oestrogen, to a lesser extent progesterone and low levels of testosterone.

These sex hormones help to relax and dilate blood vessels, reduce inflammation and improve lipid (cholesterol) levels. From the mid-40s, a decline in these hormone levels can contribute to unfavourable changes in cholesterol levels, blood pressure and weight gain – all risk factors for heart disease.

4 ways hormone changes impact heart risk

1. Dyslipidaemia– Menopause often involves atherogenic changes – an unhealthy imbalance of lipids in the blood, with higher levels of total cholesterol, triglycerides, and low-density lipoprotein (LDL-C), dubbed the “bad” cholesterol. There are also reduced levels of high-density lipoprotein (HDL-C) – the “good” cholesterol that helps remove LDL-C from blood. These changes are a major risk factor for heart attack or stroke.

2. Hypertension – Declines in oestrogen and progesterone levels during menopause contribute to narrowing of the large blood vessels on the heart’s surface, arterial stiffness and raise blood pressure.

3. Weight gain – Females are born with one to two million eggs, which develop in follicles. By the time they stop ovulating in midlife, fewer than 1,000 remain. This depletion progressively changes fat distribution and storage, from the hips to the waist and abdomen. Increased waist circumference (greater than 80–88 cm) has been reported to contribute to heart risk – though it is not the only factor to consider.

4. Comorbidities – Changes in body composition, sex hormone decline, increased food consumption, weight gain and sedentary lifestyles impair the body’s ability to effectively use insulin. This increases the risk of developing metabolic syndromes such as type 2 diabetes.

While risk factors apply to both genders, hypertension, smoking, obesity and type 2 diabetes confer a greater relative risk for heart disease in women.

So, what can women do?

Every woman has a different level of baseline cardiovascular and metabolic risk pre-menopause. This is based on their genetics and family history, diet, and lifestyle. But all women can reduce their post-menopause heart risk with:

• regular moderate intensity exercise such as brisk walking, pushing a lawn mower, riding a bike or water aerobics for 30 minutes, four or five times every week
• a healthy heart diet with smaller portion sizes (try using a smaller plate or bowl) and more low-calorie, nutrient-rich foods such as vegetables, fruit and whole grains
• plant sterols (unrefined vegetable oil spreads, nuts, seeds and grains) each day. A review of 14 clinical trials found plant sterols, at doses of at least 2 grams a day, produced an average reduction in serum LDL-C (bad cholesterol) of about 9–14%. This could reduce the risk of heart disease by 25% in two years
• less unhealthy (saturated or trans) fats and more low-fat protein sources (lean meat, poultry, fish – especially oily fish high in omega-3 fatty acids), legumes and low-fat dairy
• less high-calorie, high-sodium foods such as processed or fast foods
• a reduction or cessation of smoking (nicotine or cannabis) and alcohol
• weight-gain management or prevention.

What about hormone therapy medications?

Hormone therapy remains the most effective means of managing hot flushes and night sweats and is beneficial for slowing the loss of bone mineral density.

The decision to recommend oestrogen alone or a combination of oestrogen plus progesterone hormone therapy depends on whether a woman has had a hysterectomy or not. The choice also depends on whether the hormone therapy benefit outweighs the woman’s disease risks. Where symptoms are bothersome, hormone therapy has favourable or neutral effects on coronary heart disease risk and medication risks are low for healthy women younger than 60 or within ten years of menopause.

Depending on the level of stroke or heart risk and the response to lifestyle strategies, some women may also require medication management to control high blood pressure or elevated cholesterol levels. Up until the early 2000s, women were underrepresented in most outcome trials with lipid-lowering medicines.

The Cholesterol Treatment Trialists’ Collaboration analysed 27 clinical trials of statins (medications commonly prescribed to lower cholesterol) with a total of 174,000 participants, of whom 27% were women. Statins were about as effective in women and men who had similar risk of heart disease in preventing events such as stroke and heart attack.

Every woman approaching menopause should ask their GP for a 20-minute Heart Health Check to help better understand their risk of a heart attack or stroke and get tailored strategies to reduce it.

Treasure McGuire, Assistant Director of Pharmacy, Mater Health SEQ in conjoint appointment as Associate Professor of Pharmacology, Bond University and as Associate Professor (Clinical), The University of Queensland

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Microplastics and nanoplastics are everywhere in our environment – including in our oceans and lakes, farmland, and even Arctic ice algae.

Microplastics have also been found inside of us – with studies detecting them in various tissues including in the lungs, blood, heart and placenta. Understandably, concern is rising about the potential risks of microplastics on our health.

However, while a growing body of research has focused on microplastics and nanoplastics, there’s still a lack of direct evidence that their presence in human tissues is harmful to our health – and it’s uncertain if they are related to particular diseases.

A new study has uncovered a correlation between microplastics and heart health, though. The researchers found that people who had detectable microplastics and nanoplastics in the plaque in their arteries had a higher risk of heart attack, stroke and death.

Heart health

The researchers looked at 257 people altogether. All of the patients were already undergoing preventative surgery to remove plaque from their carotid arteries (the main arteries that supply the brain with blood). This allowed the researchers to collect plaque samples and perform a chemical analysis. They then followed up with participants 34 months later.

Of the 257 participants, 150 were found to have the presence of microplastics and nanoplastics in their arterial plaque – mainly fragments of two of the most commonly used plastics in the world, polyethylene (used in grocery bags, bottles and food packaging) and polyvinyl chloride (used in flooring, cladding and pipes).

A statistical analysis of this data found that patients with microplastics and nanoplastics in their plaque had a higher risk of suffering a heart attack, stroke or death from any cause, compared with those who had no microplastics or nanoplastics in their plaque.

The researchers also analysed the macrophages (a type of immune cell that helps remove pathogens from the body) in the patients’ arteries. They found that participants who’d had microplastics and nanoplastics in their plaque also had evidence of plastic fragments in their macrophages.

They also looked at whether certain genes associated with inflammation (which can be a sign of disease) were switched on in the participants. They found that the participants who’d had microplastics and nanoplastics in their plaque also had signs of inflammation in their genes.

These results may suggest an accumulation of nanoplastics and microplastics in carotid plaque could partly trigger inflammation. This inflammation may subsequently change the way plaque behaves in the body, making it less stable and triggering it to form a blood clot – which can eventually block blood flow, leading to heart attacks and strokes.

Interestingly, the researchers also found the presence of nanoplastics and microplastics was more common in participants who had diabetes and cardiovascular disease. This raises a lot of questions which have yet to be answered – such as why microplastics were more common in these participants, and if there may be a correlation between other diseases and the presence of microplastics in the body.

Other health risks

This study only focused on patients who had carotid artery disease and were already having surgery to remove the build-up of plaque. As such, it’s unclear whether the findings of this study can be applied to a larger population of people.

However, it isn’t the first study to show a link between microplastics and nanoplastics with poor health. Research suggests some of this harm may be due to the way microplastics and nanoplastics interact with proteins in the body.

For example, some human proteins adhere to the surface of polystyrene nanoplastics, forming a layer surrounding the nanoparticle. The formation of this layer may influence the activity and transfer of nanoplastics in human organs.

Another study suggested that nanoplastics can interact with a protein called alpha-synuclein, which in mouse studies has been shown to play a crucial role in facilitating communication between nerve cells. These clumps of nanoplastics and protein may increase the risk of Parkinson’s disease.

My published PhD research in chicken embryos found that nanoplastics may cause congenital malformations due to the way they interact with a protein called cadherin6B. Based on the interactions myself and fellow researchers saw, these malformations may affect the embryo’s eyes and neural tube, as well as the heart’s development and function.

Given the fact that nanoplastics and microplastics are found in carotid plaque, we now need to investigate how these plastics got into such tissues.

In mice, it has been demonstrated that gut macrophages (a type of white blood cell) can absorb microplastics and nanoplastics into their cell membrane. Perhaps a similar mechanism is taking place in the arteries, since nanoplastics have been identified in samples of carotid plaque macrophages.

The findings from this latest study add to a growing body of evidence showing a link between plastic products and our health. It is important now for researchers to investigate the specific mechanisms by which microplastics and nanoplastics cause harm in the body.

Meiru Wang, Postdoctoral Researcher, Molecular Biology and Nanotoxicology, Leiden University

This article is republished from The Conversation under a Creative Commons license. Read the original article.