Cardiac research: where did all the women go?

2 Jul
Where have all the women gone?
Toronto – Women have successfully broken the glass ceiling in the boardroom, in politics, and on the home front. Is it now time for women to lobby for equal representation in research trials?
According to the Heart and Stroke Foundation, more than 50 per cent of deaths caused by heart disease and stroke – the leading cause of death in Canada – are women.
But that’s a fact you would never guess if you looked at the gender balance in the crucial clinical trials that study cardiovascular disease, Dr. Wendy Tsang told the Canadian Cardiovascular Congress 2008 co-hosted by the Heart and Stroke Foundation and the Canadian Cardiovascular Society.
Dr. Tsang reviewed landmark clinical trials between January 1, 1997 and December 31, 2007 in leading medical journals The Journal of the American Medical Association (JAMA), The Lancet ,and the New England Journal of Medicine.
“These are major trials published in the world’s leading medical journals,” says Dr. Tsang who is a cardiology resident at the University of Toronto. “Trials published in these journals undergo rigorous peer and editorial review.”
Dr. Tsang’s study found that although women comprise 53 per cent of patients in the general population with cardiovascular disease, in clinical trials they represented only 29 per cent of subjects with coronary artery disease, 25 per cent with congestive heart disease, and 34% with arrhythmias. Interestingly, they represented 61 per cent of the subjects in prevention trials.
“Our study shows the proportion of women enrolled in landmark cardiovascular clinical trials is substantially lower than you would find in the general disease population. What is even more of a shock is that this under-representation has not drastically changed over the past decade, “says Dr. Tsang.
“This study shows why it’s important to put a gender lens on research,” says Heart and Stroke Foundation spokesperson Dr. Beth Abramson. “Although women should not get the wrong message − as cardiac care and treatments are proven in female patients − optimally women should be better represented in trials.”
Dr. Abramson adds that in addition to making sure women are well represented in clinical trials, we need ongoing evaluation into possible gender differences in cardiovascular disease and how to address them.
The Heart and Stroke Foundation and CIHR’s multi-provincial GENESIS research initiative − which explores the differences in how men and women experience heart disease − is a good example of how this issue can be addressed.
“A trial may show that a drug or therapy benefits patients enrolled in the trial − but if women are under-represented in the trial, it makes it difficult to tell if the outcomes of the trial can be applied to women,” says Dr. Tsang. She says that the next step in this research is to figure out what factors affect female enrollment in clinical trials in order to help address this issue.
Addressing this issue may be more difficult than it sounds. In the United States in the early 1990s the National Institutes of Health put in place a policy that said there should be a fair representation of women in trials as long as it was reasonable.
“The results of this study are even more surprising because in 1993 in the U.S. Congress passed an act to increase enrollment of women and minorities in trials,” says Dr. Tsang.  “You would have thought that between then and 2007 there would have been a change. But we didn’t find that.”
The under-representation of women in clinical trials could be because they are asked to participate less often than males. Women get heart disease later in life than men and a lot of trials have an age rule that says nobody 70 or over can enroll. However, Dr. Tsang’s research does show women make up 61 per cent of trials that investigate exercise and diet.  Could this be due to gender stereotyping?
That could be next on the research agenda.
To find out more about gender differences in heart disease and stroke visit heartandstroke.ca or thehearttruth.ca.
Statements and conclusions of study authors are solely those of the study authors and do not necessarily reflect Foundation or CCS policy or position. The Heart and Stroke Foundation of Canada and the Canadian Cardiovascular Society make no representation or warranty as to their accuracy or reliability.
The Heart and Stroke Foundation (heartandstroke.ca), a volunteer-based health charity, leads in eliminating heart disease and stroke and reducing their impact through the advancement of research and its application, the promotion of healthy living, and advocacy.

by Carolyn Thomas    @HeartSisters

Here’s a news flash:  women are not just small men (like cardiologist Dr. Nieca Goldberg‘s book of the same title). In almost every area of our health, there are significant differences between men and women’s responses to both disease and treatment.  But because women are not yet equally represented in medical research, our health care professionals have had to assume that diseases and conditions affect both women and men in the same way.  

Medical research has focused on the bikini approach to women’s health: breasts and reproductive organs. And if diagnostic tests and treatments work for men, shouldn’t they also work for women?  Well, darling readers, here are some sobering facts from the Society for Women’s Health Research that show why this may not be the case:

  • women who smoke are up to 70% more likely to develop lung cancer than men who smoke the same amount
  • women are twice as likely as men to contract a sexually transmitted disease after unprotected sex with an infected partner, and 10 times more likely to contract HIV
  • as we age, women lose more bone mass than men do, which is why 80% of people with osteoporosis are women
  • depression is 2-3 times more common in women than in men
  • some pain medications are far more effective in relieving pain in men than in women; others work better in women than in men
  • women are two times more likely than men to have a second heart attack within one year of the first one
  • even common medications like antihistamines and antibiotics can cause different reactions and/or side effects in women compared to men
  • women are more likely to develop autoimmune diseases like rheumatoid arthritis, lupus, scleroderma and multiple sclerosis

Within the past decade, science has uncovered biological and physiological differences between the sexes in virtually every organ and system of the human body.

And that is why women must – let me repeat that – MUST volunteer to participate in the research studies that will help doctors search for ways to improve the health of both men and women.

And, speaking of women not participating in medical research, why aren’t more women represented in cardiac research trials?

According to the Heart and Stroke Foundation, more women than men die each year of heart disease. And this stat has been true since 1984.

But that’s a fact you would never guess if you looked at the gender balance in  crucial clinical trials that study cardiovascular disease, University of Toronto cardiologist Dr. Wendy Tsang told the Canadian Cardiovascular Congress last fall in Toronto.

Dr. Tsang reviewed landmark clinical trials in three medical journals: The Journal of the American Medical Association, The Lancet, and the New England Journal of Medicine. She reported:

“These are major research trials published in the world’s leading medical journals. Trials published in these journals undergo rigorous peer and editorial review.”

But Dr. Tsang’s study found that although women comprise 53% of patients with cardiovascular disease, in clinical trials they represented only:

  • 29% of subjects with coronary artery disease
  • 25% with congestive heart disease
  • 34% with cardiac arrhythmia

In the early 90s in the U.S., the National Institutes of Health implemented sweeping policy changes in research protocol to ensure fair representation of women in cardiac research trials.

But Dr. Tsang explains:

“Our study shows the proportion of women enrolled in landmark cardiovascular clinical trials is substantially lower than you would find in the general disease population.

“What is even more of a shock is that this under-representation has not drastically changed over the past decade.”

So what happened?

The under-representation of women in cardiac clinical trials could be because women are asked to participate far less often than males.

We know that women do volunteer to participate in hormone or breast cancer research trials – both of which are considered women’s issues.  Many women may (mistakenly) believe that heart disease is just a man’s disease. Women also tend to develop heart disease later in life than men do; some trials have age restrictions that limit the enrollment of older participants.

However, Dr. Tsang’s research does show women do make up 61% of heart disease prevention trials that investigate exercise and diet.  Could this be due to gender stereotyping?

And speaking of older women, they are more likely than men to have more chronic illnesses like diabetes and heart disease – yet most of what doctors know about these conditions has come from studies on men under the age of 70.

Heart and Stroke Foundation spokesperson Dr. Beth Abramson adds:

“That’s why it’s important to put a gender lens on heart research. Women must be better represented in research.”

And Dr. Tsang believes that the next step in this research is to figure out what factors affect female enrollment in clinical trials in order to help address this issue.

“A research trial may show that a drug or therapy benefits patients enrolled in the trial − but if women are under-represented in the trial, it makes it difficult to tell if the outcomes of the trial can be applied to women.”

Find out more about gender differences in cardiovascular disease from The Heart Truth.  For more information about the general subject of women and medical research, visit The Society for Women’s Health Research.

© Carolyn Thomas www.myheartsisters.org

Please browse the Cardiac Research list to find clinical trials now recruiting participants.

See also:

 


6 Responses to “Cardiac research: where did all the women go?”

  1. cave76 January 13, 2012 at 12:40 pm #

    Are older adults well‐represented in clinical trials?

    “Unfortunately, despite recent improvements, older adults are significantly underrepresented in clinical drug trials”

    ***Another study published in 2001 in the Journal of the American Medical Association found that the elderly are underrepresented in the clinical trials of acute coronary syndromes (ACS).

    Despite the fact that up to 60% of Myocardial Infarction (MI) deaths occur in patients 75 years of age and older and that elderly patients experience more MI complication including heart failure, shock, and ventricular rupture, the elderly are still under‐enrolled in clinical trials compared to younger individuals. This study found that between 1966 and 1990, only 19% of ACS trials enrolled any patients 75 years of age and older.

    During this time period, the elderly accounted for a mere 2% of all patients enrolled in these trials. Since 1990, enrollment increased to 9% and for those studies published since 1995 enrollment increased to 10%. Despite minor improvements, more than half of ACS trials published from 1996 through 2000 failed to enroll at least one patient 75 or older.***

    One reason, explained in this article:

    *Older adults are also unrepresented because the trials often have exclusion criteria that are most likely to affect older adults, such as exclusions for people who have multiple diseases and take multiple medications.*

    Well, that makes some sense—– because the mixing of different drugs/conditions does not make for a neat and easily defined ‘Conclusion’.

    So what to do?

    Like

    • Carolyn Thomas January 13, 2012 at 12:57 pm #

      Thanks for this link, Cave – these appear to be the same kind of limitations that have excluded women from many cardiac studies (e.g. women’s fluctuating hormones might skew study results!)

      cheers,
      C.

      Like

  2. Bemused September 25, 2011 at 11:51 am #

    Interesting – we sign up for hormone and breast cancer studies but not heart research. NO WONDER our cardiac outcomes are comparatively bleak compared to males, when diagnostic tests and procedures are determined based on what works best for men, not for us.

    Like

  3. Townie September 23, 2011 at 8:13 pm #

    Where indeed? The less willing women are to participate in heart research, the more we’ll continue to be misdiagnosed and under-treated compared to men, based on cardiac diagnostic tools and procedures that were researched on men.

    Like

Trackbacks/Pingbacks

  1. Catherine Morgan - November 26, 2013

    […] Health Research has some interesting answers to this question. I wrote an article in 2009 called Cardiac Research: Where Did All The Women Go? on my blog Heart Sisters, including a link to compelling […]

    Like

  2. tuijianke - July 3, 2009

    I have put a link to this article from my website. Thanks.

    Like

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