Experts grapple with how heart disease affects women

Editor’s Note: This is the first of a two-part series having to do with women and heart disease or, to put a positive spin on it, heart health.

This first half will outline the emerging knowledge of how cardiac physiology is different in men and women and how this difference influences the development of heart disease in women. The second installment will have more to do with the need to apply different methods of assessing heart health in women and subsequent treatment when and if necessary.

Physiologically speaking, the differences between women and men begin at conception. Sex hormones influence physiologic development through all ages from infancy, puberty, the reproductive years and beyond.

A man and a woman can both become body builders, but the differences in each one’s musculature, skeletal physiology or neurologic physiology will remain different.

One of the most interesting new bits of knowledge is the greater understanding that even cardiovascular (having to do with the heart and blood vessels) physiology is different between men and women.

A greater awareness is coming about that when a woman is involved, she may not only experience the symptoms of heart disease differently than her male counterpart, but her symptoms may differ from what was once thought to be universally recognizable cardiac symptoms. Women may recover differently after cardiac surgery, and women may develop different late effects of heart disease – all this because of the different cardiac physiology. Heart disease in men typically involves the larger blood vessels of the heart, whereas for women, heart disease may only involve the smaller vessels of the heart.

The average life span of a woman exceeds the average life span of a man even with heart disease being the No. 1 killer in our society.

The female sex hormone, estrogen, had been assumed for many years to serve a protective function for the woman against the development of heart disease. And because of this theory, prescribers believed that continuing the heart’s exposure to this hormone in the way of hormone replacement therapy even post-menopause (that period of a women’s life when her ovaries no longer produce this hormone) would continue to protect.

This practice was based on the fact that pre-menopausal women simply did not experience heart disease at the same rate as same age-matched males. Besides helping a post-menopausal woman to deal with hot flashes, irritability, fatigue and vaginal dryness, the prescribing of hormone replacement therapy was assumed to offer secondary gains of continued protection against the development of heart disease.

As medical science gained greater understanding of the subsets of cholesterol metabolism known as HDL (“good cholesterol”) and LDL (“bad cholesterol”) we learned that LDL levels tend to rise as women begin to lose their estrogen.

In a sense, post-menopausal women are dealt a double whammy in that they no longer have estrogen to protect their hearts; they now also have higher LDL levels to contribute to the development of heart disease. It would seem to make sense to continue estrogen replacement in pill form for post-menopausal women indefinitely.

Unfortunately, this practice has fallen out of favor recently for a variety of reasons, one of which is that we now know that it’s cardio-protective benefits beyond five years of therapy no longer exerts such an influence and in fact may be detrimental to the woman’s health for a variety of other reasons. The dilemma, however, is that we cannot allow the atherosclerotic (“hardening of the arteries”) effects of elevated LDL levels to go un-checked, either.

Post-menopausal women whose LDL levels have risen over the years without being addressed are at risk for developing heart disease on a par with age-matched males. Yet, while women seem to be catching up to men in the development of heart disease, they are not being discovered or treated at the same rates as men. More about this in the second installment.

Agnes Oblas is a nurse practitioner with a private practice and residence in Ahwatukee Foothills. For questions, or if there is a topic you would like her to address, call her at (602) 405-6320 or e-mail her at agirnnp@cox.net. Her Web site is www.newpathshealth.com.