title: Association of high-density lipoprotein cholesterol with incident cardiovascular events in women, by low-density lipoprotein cholesterol and apolipoprotein B100 levels: a cohort study.
abstract: BACKGROUND
  Prior studies have found inverse associations between high-density lipoprotein cholesterol (HDL-C) or apolipoprotein A-I levels and cardiovascular disease (CVD). Whether this observation is consistent across low-density lipoprotein cholesterol (LDL-C) levels or total atherogenic particle burden (apolipoprotein B100) is less well-studied, particularly in women.
  
  
  OBJECTIVE
  To determine the association between HDL-C or apolipoprotein A-I level and CVD across a range of LDL-C and apolipoprotein B100 values.
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  The Women's Health Study, a cohort of U.S. female health professionals.
  
  
  METHODS
  26,861 initially healthy women, aged 45 years or older at study entry (1992-1995), who were followed for a mean of approximately 11 years.
  
  
  METHODS
  Baseline lipids were measured directly, and apolipoproteins were measured with immunoassays. Outcomes were incident total CVD (n = 929), coronary events (n = 602), and stroke (n = 319).
  
  
  RESULTS
  In multivariable analyses, HDL-C and apolipoprotein A-I levels were inversely associated with CVD and coronary events but not stroke. Adjusted coronary hazard ratios for decreasing quintiles of HDL-C were 1.00 (reference), 1.23 (95% CI, 0.85 to 1.78), 1.42 (CI, 0.98 to 2.06), 1.90 (CI, 1.33 to 2.71), and 2.19 (CI, 1.51 to 3.19) (P for linear trend < 0.001); corresponding hazard ratios for apolipoprotein A-I were 1.00 (reference), 0.98 (CI, 0.71 to 1.35), 1.02 (CI, 0.72 to 1.44), 1.37 (CI, 0.98 to 1.90), and 1.58 (CI, 1.14 to 2.20) (P for linear trend = 0.005). Consistent inverse associations were found for HDL-C with coronary events across a range of LDL-C values, including among women with low LDL-C levels. No associations were noted for HDL-C or apolipoprotein A-I among women with low apolipoprotein B100 values (<0.90 g/L).
  
  
  CONCLUSIONS
  Participants were at low risk for CVD, the number of events in the lowest apolipoprotein B100 stratum was small, only a single baseline measurement was obtained, and residual confounding may have occurred.
  
  
  CONCLUSIONS
  Consistent inverse associations were found for HDL-C with incident coronary events among women with a range of LDL-C values. Among women with low total atherogenic particle burden (apolipoprotein B100 level <0.90 g/L), few events occurred and no associations were seen.
  
  
  BACKGROUND
  Merck & Co. and the National Heart, Lung, and Blood Institute and National Cancer Institute, National Institutes of Health.
authors.affiliation: Center for Cardiovascular Disease Prevention, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts 02215, USA. smora@partners.org
authors.forename: Samia
authors.initials: S
authors.lastname: Mora
authors.forename: Julie E
authors.initials: JE
authors.lastname: Buring
authors.forename: Paul M
authors.initials: PM
authors.lastname: Ridker
authors.forename: Yadong
authors.initials: Y
authors.lastname: Cui
mesh_terms: D016632:Apolipoprotein A-I / Q000097:blood*; D053299:Apolipoprotein B-100 / Q000097:blood*; D002318:Cardiovascular Diseases / Q000097:blood*; D008076:Cholesterol, HDL / Q000097:blood*; D008078:Cholesterol, LDL / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008875:Middle Aged; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors
chemical_list: D016632:Apolipoprotein A-I; D053299:Apolipoprotein B-100; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL