title: Prognostic value of fasting versus nonfasting low-density lipoprotein cholesterol levels on long-term mortality: insight from the National Health and Nutrition Examination Survey III (NHANES-III).
abstract: BACKGROUND
  National and international guidelines recommend fasting lipid panel measurement for risk stratification of patients for prevention of cardiovascular events. However, the prognostic value of fasting versus nonfasting low-density lipoprotein cholesterol (LDL-C) is uncertain.
  
  
  RESULTS
  Patients enrolled in the National Health and Nutrition Examination Survey III (NHANES-III), a nationally representative cross-sectional survey performed from 1988 to 1994, were stratified on the basis of fasting status (≥8 or <8 hours) and followed for a mean of 14.0 (±0.22) years. Propensity score matching was used to assemble fasting and nonfasting cohorts with similar baseline characteristics. The risk of outcomes as a function of LDL-C and fasting status was assessed with the use of receiver operating characteristic curves and bootstrapping methods. The interaction between fasting status and LDL-C was assessed with Cox proportional hazards modeling. Primary outcome was all-cause mortality. Secondary outcome was cardiovascular mortality. One-to-one matching based on propensity score yielded 4299 pairs of fasting and nonfasting individuals. For the primary outcome, fasting LDL-C yielded prognostic value similar to that for nonfasting LDL-C (C statistic=0.59 [95% confidence interval, 0.57-0.61] versus 0.58 [95% confidence interval, 0.56-0.60]; P=0.73), and LDL-C by fasting status interaction term in the Cox proportional hazards model was not significant (Pinteraction=0.11). Similar results were seen for the secondary outcome (fasting versus nonfasting C statistic=0.62 [95% confidence interval, 0.60-0.66] versus 0.62 [95% confidence interval, 0.60-0.66]; P=0.96; Pinteraction=0.34).
  
  
  CONCLUSIONS
  Nonfasting LDL-C has prognostic value similar to that of fasting LDL-C. National and international agencies should consider reevaluating the recommendation that patients fast before obtaining a lipid panel.
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: Bethany
authors.initials: B
authors.lastname: Doran
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: Yu
authors.initials: Y
authors.lastname: Guo
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Xu
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: Howard
authors.initials: H
authors.lastname: Weintraub
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: Samia
authors.initials: S
authors.lastname: Mora
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.).
authors.forename: David J
authors.initials: DJ
authors.lastname: Maron
authors.affiliation: From New York University School of Medicine, New York, NY (B.D., Y.G., J.X., H.W., S.B.); Brigham and Women's Hospital, Boston, MA (S.M.); and Stanford University School of Medicine, Department of Medicine, Stanford, CA (D.J.M.). sripalbangalore@gmail.com.
authors.forename: Sripal
authors.initials: S
authors.lastname: Bangalore
mesh_terms: D000328:Adult; D002318:Cardiovascular Diseases / Q000097:blood* / Q000175:diagnosis / Q000401:mortality*; D015331:Cohort Studies; D005215:Fasting / Q000097:blood*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008077:Lipoproteins, LDL / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009026:Mortality / Q000639:trends; D009749:Nutrition Surveys / Q000639:trends; D011379:Prognosis; D013997:Time Factors
chemical_list: D008077:Lipoproteins, LDL
keywords: cholesterol; mortality