There is an ongoing controversy as to whether hormone therapy is protective of coronary heart disease. If so, whether this makes a difference to coronary protection if the hormone therapy is started in early menopause, begun years after the menopausal transition, or continued for many years. This is an extraordinarily important issue…Coronary heart disease (CHD) is the leading cause of death among women. According to the American Heart Association 2015 update on heart disease statistics, the annual number of women diagnosed as having a heart attack or fatal CHD is 35 per 1000 among women aged 45 to 54 years, 60 per 1000 women aged 55 to 74 years, and 70 per 1000 among women aged 65 to 74. (Wow! Wouldn’t it be great if we could state that something that reduces bone loss and fractures, improves hot flashes, night sweats and vaginal dryness, and perhaps even confers a level of protection against dementia, would also reduce heart attacks!)
There is a new study from Sweden that was published in the Journal “Menopause” about HT and coronary protection that was somewhat positive (or at least not negative). The authors tried to assess whether hormonal therapy reduces myocardial infarction (MI) risk if initiated early after menopause. They did what is termed a population based case-control study through their Stockholm heart epidemiology program (SHEEP…I love this abbreviation). The study base was composed of postmenopausal women aged 45 to 70 who had not had a previous diagnosis of MI and who were citizens living in Stockholm County between January 1992 and December 1994. They identified 538 women who had a nonfatal heart attack and matched them with 797 control women. After performing the usual complicated statistical analysis, they found that the use of hormone therapy was not significantly associated with risk of MI. They also did not find that the timing of initiation of hormone therapy in relation to onset of menopause nor the duration of therapy were significantly associated with risk.
But could they also state that HT decreased MI risk? Unfortunately, they were not able to do so within the bounds of major statistical significance. Here are the numbers: Initiation of hormone therapy within 10 years of onset of menopause or before age 60 compared with never use was associated with an odds ratio of 0.87 for MI after adjustments for lifestyle factors such as body mass index and socioeconomic status. (That means there was a 13% decrease in risk for those on HT when compared to the women who are not on hormones.) For late initiation of hormone therapy, the odds ratio was -0.97 (this is essentially zero) and for hormone therapy duration of five years or more compared with never use the adjusted odds ratio was 0.64. For hormone therapy duration of less than five years, the odds ratio was 0.97 (also essentially zero). The authors concluded that based on their study “that neither the timing of HT initiation nor the duration of the therapy is significantly associated with the risk of an MI.” However, their results “show some tendencies of inverse relations between hormone therapy and MI”. In other words the longer the use the somewhat lower the risk. They go on to say, as do many authors of other studies, that “the precision of their study is not high enough to draw robust conclusions and further studies are needed on the larger populations, including detailed information on the hormone therapy used and potential confounding factors.”
All in all, it’s one more study that seems to show at least that hormone therapy doesn’t increase risk and perhaps may help decrease the risk of heart attack… Once again, before that reassuring statement can definitively be made and is accepted by all the major medical players, we need more studies. But I thought I would share…