title: Effect of postmenopausal hormone therapy on lipoprotein(a) concentration. PEPI Investigators. Postmenopausal Estrogen/Progestin Interventions.
abstract: BACKGROUND
  Postmenopausal hormone therapy has been reported to decrease levels of lipoprotein (Lp)(a) in cross-sectional studies and small or short-term longitudinal studies. We report findings from a large, prospective, placebo-controlled clinical trial that allows a broad characterization of these effects for four regimens of hormone therapy.
  
  
  RESULTS
  The Postmenopausal Estrogen/Progestin Interventions study was a 3-year, placebo-controlled, randomized clinical trial to assess the effect of hormone regimens on cardiovascular disease risk factors in postmenopausal women 45 to 65 years of age. The active regimens were conjugated equine estrogens therapy at 0.625 mg daily, alone or in combination with each of three regimens of progestational agents: medroxyprogesterone acetate (MPA) at 2.5 mg daily (ie, continuous MPA), MPA at 10 mg days 1 to 12 (ie, cyclical MPA), and micronized progesterone at 200 mg days 1 to 12. Plasma levels of Lp(a) were measured at baseline (n = 366), 12 months (n = 354), and 36 months (n = 342). Assignment to hormone therapy resulted in a 17% to 23% average drop in Lp(a) concentrations relative to placebo (P<.0001), which was maintained across 3 years of follow-up. No significant differences were observed among the four active arms. Changes in Lp(a) associated with hormone therapy were positively correlated with changes in LDL cholesterol, total cholesterol, apolipoprotein B, and fibrinogen levels and were similar across subgroups defined by age, weight, ethnicity, and prior hormone use.
  
  
  CONCLUSIONS
  Postmenopausal estrogen therapy, with or without concomitant progestin regimens, produces consistent and sustained reductions in plasma Lp(a) concentrations.
authors.affiliation: Section on Biostatistics, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, NC 27157-1063, USA. mespelan@rc.phs.bgsm.edu
authors.forename: M A
authors.initials: MA
authors.lastname: Espeland
authors.forename: S M
authors.initials: SM
authors.lastname: Marcovina
authors.forename: V
authors.initials: V
authors.lastname: Miller
authors.forename: P D
authors.initials: PD
authors.lastname: Wood
authors.forename: C
authors.initials: C
authors.lastname: Wasilauskas
authors.forename: R
authors.initials: R
authors.lastname: Sherwin
authors.forename: H
authors.initials: H
authors.lastname: Schrott
authors.forename: T L
authors.initials: TL
authors.lastname: Bush
mesh_terms: D000368:Aged; D002318:Cardiovascular Diseases / Q000209:etiology / Q000517:prevention & control; D003430:Cross-Sectional Studies; D015914:Estrogen Replacement Therapy; D004967:Estrogens / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000097:blood*; D017258:Medroxyprogesterone Acetate / Q000008:administration & dosage*; D008875:Middle Aged; D017698:Postmenopause / Q000097:blood*; D011374:Progesterone / Q000008:administration & dosage*; D045167:Progesterone Congeners / Q000008:administration & dosage*; D012307:Risk Factors; D016896:Treatment Outcome
chemical_list: D004967:Estrogens; D017270:Lipoprotein(a); D045167:Progesterone Congeners; D011374:Progesterone; D017258:Medroxyprogesterone Acetate