May 2004

Drug companies failed to make HRT risks public

Drug companies and researchers funded by them knew of the risks of hormone replacement years before the information was released to the public, according to an article that appeared in the BMJ (formerly, the British Medical Journal). As a result, women were needlessly exposed to an increased risk of heart disease, said Drs. Klim McPherson and Elina Hemminki, co‑authors of the BMJ report.

In 2002, a large research trial by the Women's Health Initiative trial was halted after it showed an increased risk of cardiovascular events from combined hormone replacement therapy.

However, well before the Women's Health Initiative trial was published, McPherson and Hemminki had analyzed 23 small trials of hormone replacement therapies and found that, contrary to claims by the drug makers, HRT did not prevent coronary disease. Instead, the research often showed that certain HRT therapies actually increased the risk of heart disease.

Yet, many of these trials were done by pharmaceutical companies to obtain drug

licenses and were not made available to the public or the medical community. In fact, the BMJ authors had to get a court order to allow them to have access to some of the data needed for their research. When they did make their report, they were criticized, since their conclusions were not supported by published research. They recalled: "When we published these findings in 1997, we were ridiculed. 'For one, I shall continue to tell my patients that hormone replacement therapy is likely to help prevent coronary disease,' asserted one expert commentator."

Only after the Women's Health Initiative trial were their findings validated. "Reliably assessing the safety of drugs, however, is fraught with problems such as rare events, long follow up, strong vested interests, and biased reporting," they explained, adding that "At least 200 trials had studied the impact of hormones on physiological phenomena, laboratory values, osteoporosis, symptoms, or various health problems but few fully reported adverse effects." Many of the studies were not publicly available.

The authors called for new regulations that would force drug companies to include data on risks, side effects and ineffectiveness ‑ and make all findings publicly accessible. "This is not a great deal to ask, given the importance of the questions," they concluded. "How long will it take us to learn? How many women were needlessly exposed to an increased risk of cardiovascular disease?"

SOURCE: "Synthesising licensing data to assess drug safety," by Klim McPherson and Elina Hemminki, BMJ, February 2004.

NOTE: This article appeared in the World Chiropractic Alliance Health Watch electronic newsletter. To receive this free newsletter each week, sign up at Health Watch.