Predicting HRT response still not a reality. (Beyond One-Size-Fits-All Therapy).

NEW ORLEANS -- Research has along way to go before physicians will be able to predict how an individual woman's circulating hormone levels will respond to a specific hormone replacement therapy regimen, Dr. Elizabeth Barrett-Connor said at the annual meeting of the North American Menopause Society.

Endogenous estrogen levels at baseline and adiposity offer some dues as to who may need estrogen. Thin women and older women tend to have low endogenous estrogen levels and are easy to identify as treatment candidates. But moving away from a one-size-fits-all approach to hormone replacement therapy (HRT) and figuring out how each woman's hormone profile will respond to a specific regimen and dosage--and having therapeutic targets to shoot for--are all still goals for researchers rather than the reality of everyday practice, said Dr. Barrett-Connor, professor and chief of the division of epidemiology at the University of California, San Diego.

In a study aimed at investigating the determinants of change in estrogen levels in response to various HRT regimens, Dr. Barrett-Connor and her colleagues examined data from 823 participants in the Postmenopausal Estrogen/Progestin Interventions trial.

All participants in Dr. Barrett-Connor's analysis had their estrone, estradiol, and bioavailable levels of estradiol measured at baseline and again 24 months after starting one of five therapies. The therapies included placebo, estrogen alone, or one of three estrogen plus progestin HRT regimens as part of the randomized controlled trial funded by the National Institutes of Health.

At baseline, factors associated with low levels of endogenous estrogen included being at least 55 years old, having a low body mass index (BMI), and smoking. Smokers had higher levels ...