title: Lp(a) lipoprotein: relationship to cardiovascular disease risk factors, exercise, and estrogen.
abstract: OBJECTIVE
  Lp(a) lipoprotein is a distinct lipoprotein particle that recently has been found to be associated with cardiovascular disease. A study was conducted to assess the influence of cardiovascular disease risk factors on levels of Lp(a) and to evaluate the effects of age, exercise, and estrogen on these levels.
  
  
  METHODS
  Two studies, a cross-sectional study of older men (n = 105) and women (n = 75) (mean age 76 years) and a prospective study of younger postmenopausal women (mean age 48 years), were carried out. Lp(a) and other lipoproteins were measured in the two studies and differences were sought by statistical analysis.
  
  
  RESULTS
  In the cross-sectional study, serum Lp(a) was similar in men and women and was not influenced by age. Lp(a) levels in men and women were higher when there was more than one cardiovascular disease risk factor present (p less than 0.028). We could not demonstrate such a relationship with other lipid and lipoprotein measurements. In the prospective study exercise alone had no influence on Lp(a) levels. Oral estrogen decreased Lp(a) levels marginally (p = 0.08). The decrease in Lp(a) with oral estrogen was associated with increases in triglycerides (p less than 0.01) and very-low-density lipoprotein (p less than 0.06).
  
  
  CONCLUSIONS
  These data confirm that elevated Lp(a) levels are an independent risk factor for cardiovascular disease. Lp(a) levels are primarily influenced by genetic factors and it appears estrogen may have a minor influence on its hepatic synthesis.
authors.affiliation: Department of Obstetrics and Gynecology, University of Southern California School of Medicine, Los Angeles, CA 90033.
authors.forename: R A
authors.initials: RA
authors.lastname: Lobo
authors.forename: M
authors.initials: M
authors.lastname: Notelovitz
authors.forename: L
authors.initials: L
authors.lastname: Bernstein
authors.forename: F Y
authors.initials: FY
authors.lastname: Khan
authors.forename: R K
authors.initials: RK
authors.lastname: Ross
authors.forename: W L
authors.initials: WL
authors.lastname: Paul
mesh_terms: D000375:Aging / Q000097:blood; D002318:Cardiovascular Diseases / Q000209:etiology*; D002784:Cholesterol / Q000097:blood; D004967:Estrogens / Q000494:pharmacology*; D015444:Exercise; D005260:Female; D006801:Humans; D002546:Ischemic Attack, Transient / Q000097:blood; D017270:Lipoprotein(a); D008074:Lipoproteins / Q000097:blood*; D008297:Male; D008593:Menopause / Q000097:blood; D008875:Middle Aged; D012307:Risk Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D004967:Estrogens; D017270:Lipoprotein(a); D008074:Lipoproteins; D014280:Triglycerides; D002784:Cholesterol