Experts in Europe say assessment tools are underestimating risk—how does Australia’s calculator stack up.

Incidence and mortality rates of atherosclerotic cardiovascular disease are rising globally, and the fastest relative increase in mortality is occurring in middle-aged women.

This has prompted an urgent call to action from the European Atherosclerosis Society, which published a position statement calling for earlier assessment and treatment of modifiable cardiovascular risk factors in women—especially those with female-specific risk factors such as PCOS, gestational diabetes, pre-eclampsia, and early menopause or premature ovarian insufficiency.

The European Atherosclerosis Society notes that:

• Missed or delayed diagnosis and undertreatment all play a role
• Women are less likely to be prescribed guideline-recommended preventative treatment for hyperlipidaemia than men
• Pregnancy, breastfeeding and menopause can all impact lipids, and lipid profiles worsen after menopause
• Lipoprotein(a) increases in pregnancy and from the onset of menopause

Meanwhile fewer than 1% of eligible women are getting heart health checks, longitudinal research published in the Medical Journal of Australia last month suggests.

Between January 2013 and August 2021, just 44 women out of 10,162 women who were born between 1973 and 1978 in the Australian Longitudinal Study on Women’s Health had a heart health check, and just 10% had at least one general health check.

The authors of the position statement point to genetic and hormonal factors specific to women that impact on their risk. These include the genetic variant that predisposes women to familial hypercholesteremia, as well as hormonal changes around menopause that effect cholesterol levels, particular, lipoprotein(a).

As a result, they say current cardiovascular risk prediction models are biased against women, resulting in an under-estimate of the actual risk, and that the focus should change from a 10-year focus to a lifetime focus.

“Women-specific risk factors are rarely incorporated when developing cardiovascular risk prediction models, given limited supportive evidence. Thus, the concepts of lifetime cardiovascular risk and treatment benefit are promising approaches to tailoring ASCVD prevention in women,” the position statement argues.

How does the new CVD tool stack up?

So, where does Australia’s recently updated cardiovascular risk assessment tool stand? The Heart Foundation’s Healthcare Programs Manager Natalie Raffoul is confident it’s up to the job.

“Overall, the algorithm that we’ve developed is pretty robust,” she says. “It’s our first risk equation that has been modified and recalibrated for the Australian population.”

She says the new calculator has more variables, including diabetes specific variables that support a more accurate assessment of risk in people with diabetes.

It also includes “reclassification factors” that GPs can consider to help either bump up or bump down the risk category for that individual.

“These are things like whether or not you have a coronary artery calcium score available and what that score is, your ethnicity, your family history, your renal function, presence of severe mental illness—all of these things can be factored in,” Raffoul explains.

When it comes to specifics like preeclampsia, PCOS or premature ovarian insufficiency, she says that “there’s not enough evidence right now to say that they need to be factored into formal calculations independently, as the algorithm will automatically pick up on their risk once their blood pressure is entered.”

“There’s not enough evidence right now to say that they need to be factored into your formal calculation of cardiovascular risk in your patients. It’s something that I think we probably need a bit more data on,” she says, but “they certainly should be screened earlier.”

Lipoprotein(a) and menopause

The European Atherosclerosis Society is also calling for changes in the way we monitor lipoprotein(a) around the menopause.

It says lipoprotein(a) rises in pregnancy and again around menopause and may increase a woman’s heart disease risk, so “repeat measurement may be indicated”.

But again, Raffoul says there’s not enough evidence to suggest retesting specifically for it, though she agrees that keeping an eye on lipids in general in post-menopausal women is wise.

“Definitely in women over 50, menopause really plays around with lipids. Not only is lipoprotein(a) elevated in women over 50, particularly post menopause, but the lipid profile overall changes. Your total cholesterol, your LDL, your HDL – all of that worsens after menopause as well. So, it is absolutely a good idea to keep an eye on a woman’s lipid levels when she’s approaching menopause and afterwards. It’s another reason to keep having more regular checks with women that are experiencing menopause symptoms or even premature menopause or early menopause.”

The Heart Foundation has developed data templates that general practices can use to go through their clinical records and identify women that may have been diagnosed with certain conditions that increase their risk, for example, gestational diabetes so they can be called in for a heart health check.

Raffoul says Australia does quite well at blood pressure management in patients who are engaged with the health system— she says generally aiming for a systolic blood pressure of under 140mmhg is fine, but in people who are at higher risk we should be aiming to get that somewhere between 120-130mmhg.

One area where Raffoul would like to see improvement is in cholesterol management.

“We know that the majority of people do not meet their lipid targets, even when they are on medication, or even in the secondary prevention setting. So, there’s a lot of work that we have to do to not only to screen people and assess them really well but then manage them more appropriately,” she says.

One group the European Atherosclerosis Society mentioned as requiring close attention was women with familial hypercholesterolemia.

“This paper certainly is drawing out that women could be at higher risk of the burden of familial hypercholesterolemia compared to men,” but she says GPs will have already screened patients at risk and should be monitoring them closely already.

Raffoul says the Heart Foundation has been working hard to raise awareness of the unique risk-factors and the different ways heart disease presents in and effects women, and this will continue.

Resources:
https://www.heartfoundation.org.au/Bundles/For-Professionals