Endogenous reproductive hormones and C-reactive protein across the menstrual cycle: the BioCycle Study.
C-reactive protein (CRP) is one of the most commonly used markers of acute phase reaction in clinical settings and predictors of cardiovascular risk in healthy women; however, data on its physiologic regulation in premenopausal women are sparse. The objective of this study was to evaluate the association between endogenous reproductive hormones and CRP in the BioCycle Study (2005-2007). Women aged 18-44 years from western New York were followed prospectively for up to 2 menstrual cycles (n = 259). Serum levels of CRP, estradiol, progesterone, luteinizing hormone, and follicle-stimulating hormone were measured up to 8 times per cycle, timed by fertility monitors. CRP levels varied significantly across the cycle (P < 0.001). More women were classified as being at elevated risk of cardiovascular disease (CRP, >3 mg/L) during menses compared with other phases (12.3% vs. 7.4%; P < 0.001). A 10-fold increase in estradiol was associated with a 24.3% decrease in CRP (95% confidence interval: 19.3, 29.0). A 10-fold increase in luteal progesterone was associated with a 19.4% increase in CRP (95% confidence interval: 8.4, 31.5). These results support the hypothesis that endogenous estradiol might have antiinflammatory effects and highlight the need for standardization of CRP measurement to menstrual cycle phase in reproductive-aged women.
Division of Epidemiology, Statistics, and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, Bethesda, Maryland, USA.
Audrey J
AJ
Gaskins
Machelle
M
Wilchesky
Sunni L
SL
Mumford
Brian W
BW
Whitcomb
Richard W
RW
Browne
Jean
J
Wactawski-Wende
Neil J
NJ
Perkins
Enrique F
EF
Schisterman
D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D002097:C-Reactive Protein / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000097:blood; D004958:Estradiol / Q000097:blood*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D007249:Inflammation / Q000097:blood; D016014:Linear Models; D007986:Luteinizing Hormone / Q000097:blood*; D008597:Menstrual Cycle / Q000097:blood*; D011374:Progesterone / Q000097:blood*; D011446:Prospective Studies; D018570:Risk Assessment; D055815:Young Adult
D015415:Biomarkers; D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D002097:C-Reactive Protein