The results of another arm of the definitive government study known as the Women's Health Initiative finds that combined HRT in women 65 and older doesn't prevent dementia – it may cause it, reports CBS News Medical Correspondent Elizabeth Kaledin.
"What we found is that women in the combination hormone replacement therapy had twice the risk of developing dementia as compared to women on placebo," said the study's lead investigator, Dr. Sally Shumaker of the Wake Forest University School of Medicine.
The study followed more than 4,500 women over four years, testing the theory that the estrogen/progestin cocktail might help stave off the dementia and memory loss that often accompanies old age.
But Shumaker says what they found "was exactly the opposite – that combination therapy significantly increased harm."
Seventy-six-year-old Natalie Gordon has participated in the study since 1998, filing away every letter and document. She signed up hoping the HRT would prevent osteoporosis. Now, instead of worrying about strong bones, she'll be second-guessing the strength of her mind.
"I'm not certain that I am seeing a certain breakdown but I watch for it all the time," says Gordon.
The new study comes less than a year after another major report finding that HRT also increases risks for heart disease, blood clots, strokes and breast cancer, leaving many to wonder if anyone should be taking these drugs at all.
The answer, surprisingly enough, is yes. Many doctors say short-term in low doses, the drugs do help younger women suffering debilitating menopausal symptoms. But for anyone older the message should by now be crystal clear:
"If you're a woman 65 and older there's absolutely no reason I could imagine why you'd take combination hormone therapy," says Shumaker.
When it comes to weighing risks and benefits of hormone replacement therapy, the guess work is over.