Endothelial function and cardiovascular risk stratification in menopausal women

Abstract

Background Peripheral arterial, endothelium-dependent, flow-mediated reactive hyperemia is reduced in individuals with atherosclerosis. This study tested the hypothesis that digital tonometry, as a surrogate of endothelial function, is useful to stratify cardiovascular risk in recently menopausal women who are asymptomatic for cardiovascular disease.

Methods Women undergoing screening for the Kronos Early Estrogen Prevention Study (KEEPS) were evaluated for conventional risk factors, flow-mediated reactive hyperemia by digital tonometry (RHI), carotid intima-media thickness (CIMT) by ultrasound, and coronary arterial calcium (CAC) by 64-slice CT scanner.

Results One hundred and two non-diabetic Caucasian women (53.0 ± 2.3 years old, 18.0 ± 9.0 months past their last menses) participated; 72% were never-smokers. Fourteen women had positive CAC scores (range 0.5–133 Agatston units); CIMT ranged from 0.57 to 1.06 mm. RHI ranged from 1.26 to 5.44. RHI did not correlate with time past menopause, CAC, CIMT, total cholesterol or low density lipoprotein cholesterol. The significant negative correlation of RHI with body mass index (r = −0.21, p = 0.031) was lost in non-smokers (r = − 0.17, p = 0.14). There was also a negative correlation of high density lipoprotein cholesterol with CAC, both in the overall group and non-smokers (ρ = −0.20, p = 0.05 and ρ = −0.27, p = 0.02, respectively).

Conclusions RHI varies widely in healthy women within the first 3 years of menopause. RHI was not associated with standard risk assessment algorithms, CAC or CIMT. RHI may indicate an additional, independent component and non-invasive tool to further stratify cardiovascular risk in recently menopausal women. As KEEPS continues, data on RHI will provide information regarding hormonal therapy, endovascular biology and atherosclerotic risk.

Key words:

• ATHEROSCLEROSIS
• CORONARY DISEASE
• ENDOTHELIUM
• HORMONES

Acknowledgements

The authors thank the women participating in this study and the study staff who are part of the KEEPS team.

Conflict of interest  The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Source of funding  The Kronos Early Estrogen Prevention Study (KEEPS) is funded by the Kronos Longevity Research Institute, Phoenix, AZ, USA. This ancillary study was made possible by funding from the Division of Cardiovascular Diseases, Department of Internal Medicine, Mayo Clinic. (KEEPS; NCT00154180) http://www.clinicaltrials.gov/show/NCT00154180