title: Effect of age on the exercise response in normal postmenopausal women during estrogen replacement therapy.
abstract: Postmenopausal estrogen replacement therapy (ERT) has been associated with a reduced risk of coronary artery disease (CAD). Whether this apparent cardioprotective effect is mediated by a cardiovascular benefit during exercise, however, has not been clearly defined. To evaluate rest and exercise variables with and without ERT, a randomized crossover trial was conducted in 23 postmenopausal women, ranging in age from 44 to 75 years, mean age 57+/-8 years. The rest and exercise variables were compared on ERT and during a drug-free period. The baseline measure was compared to the effects after 4 weeks of ERT and after 4 drug-free weeks. Echocardiographic treadmill exercise variables of heart rate (HR), blood pressure, rate-pressure product (RPP), and cardiac dimensions were determined at baseline and at the end of each treatment period. In response to ERT, there was a decrease in low-density lipoprotein (LDL) cholesterol (drug-free: 142+/-40 mg/dl, ERT: 124+/-34 mg/dl) and an increase in high-density lipoprotein (HDL) cholesterol (drug-free: 52+/-14 mg/dl, ERT: 62+/-15 mg/dl, both p<0.01). At rest, the study population had no overall significant change in HR, blood pressure, RPP, or left ventricular end-systolic and end-diastolic diameters when ERT was compared to the drug-free period. However, subjects with the fastest baseline resting HR had the greatest decrease in HR with ERT relative to the drug-free period (p<0.05). During exercise, ERT effected no change in peak HR, blood pressure, or RPP, although end-systolic diameter decreased slightly (p<0.05). With ERT, subject age correlated negatively with systolic blood pressure (p<0.05) and RPP (p<0.01); both blood pressure and RPP decreased in older subjects. In conclusion, ERT has differential effects dependent on baseline HR and age.
authors.affiliation: Center for Women's Health, Department of Medicine, College of Physicians & Surgeons, Columbia University, New York, New York, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Seminario
authors.forename: R R
authors.initials: RR
authors.lastname: Sciacca
authors.forename: M R
authors.initials: MR
authors.lastname: DiTullio
authors.forename: S
authors.initials: S
authors.lastname: Homma
authors.forename: E G
authors.initials: EG
authors.lastname: Giardina
mesh_terms: D000328:Adult; D000368:Aged; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D003327:Coronary Disease / Q000000981:diagnostic imaging / Q000517:prevention & control*; D018592:Cross-Over Studies; D004452:Echocardiography / Q000187:drug effects*; D015914:Estrogen Replacement Therapy; D004966:Estrogens, Conjugated (USP) / Q000008:administration & dosage* / Q000009:adverse effects; D005080:Exercise Test / Q000187:drug effects*; D005260:Female; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D008875:Middle Aged; D017698:Postmenopause; D012307:Risk Factors; D016037:Single-Blind Method
chemical_list: D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D004966:Estrogens, Conjugated (USP)