There is no link between the menopause and increased risk of fatal heart attack, say Johns Hopkins researchers who report their findings in the 6 September online issue of the British Medical Journal, BMJ. They found that the increasing number of deaths from heart attack as women get older is not due to the menopause but aging alone and not hormonal changes. They were also surprised to find evidence suggesting that something biological happens to young men up to the age of 45 that raises their heart risk and propose we should be paying more attention to that.

Instead of the long-held belief that cardiovascular risk in women spikes just after the menopause, the Johns Hopkins research points towards the risk rising at a constant rate over the whole lifespan.

Study leader Dr Dhananjay Vaidya, an assistant professor of medicine at the Johns Hopkins University School of Medicine, told the press:

“Our data show there is no big shift toward higher fatal heart attack rates after menopause.”

“What we believe is going on is that the cells of the heart and arteries are aging like every other tissue in the body, and that is why we see more and more heart attacks every year as women age. Aging itself is an adequate explanation and the arrival of menopause with its altered hormonal impact does not seem to play a role,” he added.

The implications are that perhaps more attention should be paid to women’s heart health before the menopause, since this study suggests that is not negligible, as previously thought.

The researchers are not saying that menopause has no effect in the risks of other diseases. For instance, the rate of breast cancer deaths goes down faster at menopause, probably because of the changes in hormone levels, said Vaidya.

For their study, the researchers analyzed rates of death among people born in England, Wales and the USA between 1916 and 1945.

They followed the trends among groups of similar people as they aged and found that around the age of the menopause in each group, there was no rise in deaths among women over and above the steady curve expected from aging.

Vaidya said the death rate curve increases annually in a similar way to compound interest: the rate stays steady at 8% a year, but the risk accumulates, getting bigger as each year goes by.

Absolute mortality, said Vaidya, increases at all ages with no abrupt change at the time of the menopause.

What the team also found surprising were what they saw in the curves for men. We have known for some time that the risk of dying from heart disease hits men earlier in life than women, but what Vaidya and colleagues found was that the mortality curve for men under 45 years of age went up by 30% a year, and only slowed down after the age of 45 to around 5% a year.

Overall, this was similar to the rate throughout the lifetime for women (thus coming back to the compound interest analogy, after around midlife, assuming both invested the same capital sum, both men and women will have accrued the same amount of interest, or risk, just women at a steady rate of 8% and men at a fast rate of 30% followed by 5% after the age of 45).

This suggests something biological is happening in younger men that could be putting their hearts at risk.

“Instead of looking at menopause, what we should be looking at is what is happening biologically to men over time,” urged Vaidya, explaining that they don’t have an answer, it’s just that “good research always creates more questions.”

One possible explanation is there are differences between men and women in terms of what happens to their telomeres. These are the ends of chromosomes that protect important genes (think of the hard plastic ends of shoelaces that stop them fraying). Every time DNA is copied, a bit of telomere is lost. This happens each time cells divide, until the point is reached where genes get damaged, and that is the damaging effect of aging on cells.

We know that while male and female babies have the same telomere lengths, by the time the male babies reach young adulthood, these will be significantly shorter than that of their female couterparts, but then later in life, the rate of them getting shorter is about the same in both sexes. The researchers wonder if this might account for the higher risk of death from heart disease at younger ages for men, and then both sexes having similar heart disease mortality rates later in life.

The data revealed some good news too: comparing groups according to the year they were born, each successive group had lower total and heart disease death rates over their lifetime, which the researchers said was most likely because of better nutrition, better quality of life, preventive medical care, drugs and other treatments for heart disease.

Vaidya urged doctors to ensure that they assess cardiovascular health in their female patients from an early age, and make sure they follow healthy heart habits.

“Special attention should be paid to heart health in women due to their overall lifetime risk – not just after the time of menopause,” said Vaidya.

Written by Catharine Paddock PhD