To the Editor.
—Whether estrogen replacement therapy (ERT) prevents increases in body fat in postmenopausal women is of significant medical and public health interest. Evidence that ERT does not prevent increases in weight in postmenopausal women was recently reported on the Rancho Bernardo cohort by Drs Kritz-Silverstein and Barrett-Connor.1 However, methodologic approaches may have obscured a real association.In the authors' analysis, body mass index (BMI) was used as the indicator of change in body fat. However, Roubenoff et al2 recently reported BMI to be a biased indicator of body fatness in older women. Further, examining changes in BMI is problematic in aging female populations because women who maintain their weight but lose height show an increase in BMI. Since ERT preserves bone, postmenopausal women who do not use estrogens may lose more height than postmenopausal women who use estrogens. It would be interesting for Kritz-Silverstein and Barrett-Connor
Blackman JA. Estrogen Replacement Therapy and Body Fat. JAMA. 1996;275(13):987. doi:10.1001/jama.1996.03530370025021