Neurocognitive outcomes are not improved by 17β-estradiol in postmenopausal women undergoing cardiac surgery

Background and Purpose - Neurocognitive dysfunction is an important source of patient morbidity and mortality after cardiac surgery that may disproportionately affect postmenopausal women. 17 beta-Estradiol limits the extent of ischemic neuronal injury in a variety of experimental models. The purpose of this study was to evaluate whether perioperative administration of 17 beta-estradiol to postmenopausal women reduces the frequency of neurocognitive dysfunction after cardiac surgery. Methods - One hundred seventy-four postmenopausal women not on estrogen replacement therapy who were undergoing primary coronary artery bypass graft surgery and/or valve surgery with cardiopulmonary bypass were prospectively randomized to receive in a double-blinded manner either 17 beta-estradiol or placebo beginning the day before surgery and continuing for 5 days postoperatively. The patients were evaluated before and after surgery with the National Institutes of Health Stroke Scale and a psychometric test battery. Results - There were no differences in the frequency of neurocognitive dysfunction (primary outcome) between patients randomized to perioperative 17 beta-estradiol (n = 86) and those randomized to placebo (n = 88) 4 to 6 weeks after surgery (17 beta-estradiol, 22.4% versus placebo, 21.4%, P = 0.45). The mean scores on tests of psychomotor speed were worse in women in the 17 beta-estradiol group than in the placebo group at the 4- to 6-week (P = 0.005) postoperative testing sessions. Conclusions - Perioperative treatment with 17 beta-estradiol did not result in improved neurocognitive outcomes in postmenopausal women undergoing cardiac surgery.