Small apolipoprotein(a) size predicts mortality in end-stage renal disease: The CHOICE study

Circulation. 2002 Nov 26;106(22):2812-8. doi: 10.1161/01.cir.0000038946.91899.bb.

Abstract

Background: The high mortality rate in end-stage renal disease has engendered interest in nontraditional atherosclerotic cardiovascular disease (ASCVD) risk factors that are more prevalent in end-stage renal disease, such as elevated lipoprotein(a) [Lp(a)] levels. Previous studies suggest that high Lp(a) levels and small apolipoprotein(a) [apo(a)] isoform size are associated with ASCVD, but none have investigated the relationship between Lp(a) level, apo(a) size, and mortality.

Methods and results: An inception cohort of 864 incident dialysis patients was followed prospectively. Lp(a) was measured by an apo(a) size-independent ELISA and apo(a) size by Western blot after SDS-agarose gel electrophoresis. Comorbid conditions were determined by medical record review. Time to death was ascertained through dialysis clinic and Health Care Financing Administration follow-up. Survival analyses were performed with adjustment for baseline demographic, comorbid conditions, albumin, and lipids. Median follow-up was 33.7 months, with 346 deaths, 162 transplantations, and 10 losses to follow-up during 1999 person-years of follow-up. Cox regression analysis showed no association between Lp(a) level and mortality. However, an association between small apo(a) isoform size and mortality was found (hazard ratio, 1.36; P=0.004) after adjusting for age, race, sex, comorbidity score, cause of renal disease, and congestive heart failure. The association was somewhat lower in white patients (hazard ratio 1.34; P=0.019) than in black patients (1.69; P=0.04). No interaction by age, race, sex, diabetes, ASCVD, or Lp(a) level was present.

Conclusions: Small apo(a) size, but not Lp(a) level, independently predicts total mortality risk in dialysis patients.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Aged
  • Apolipoproteins / blood*
  • Apolipoproteins / chemistry
  • Apoprotein(a)
  • Biomarkers / blood
  • Biomarkers / chemistry
  • Black People
  • Black or African American
  • Blotting, Western
  • Cohort Studies
  • Enzyme-Linked Immunosorbent Assay
  • Female
  • Humans
  • Kidney Failure, Chronic / blood*
  • Kidney Failure, Chronic / mortality*
  • Lipoprotein(a) / blood*
  • Lipoprotein(a) / chemistry
  • Male
  • Middle Aged
  • Particle Size
  • Predictive Value of Tests
  • Proportional Hazards Models
  • Prospective Studies
  • Risk Factors
  • Survival Rate
  • United States / epidemiology
  • White People

Substances

  • Apolipoproteins
  • Biomarkers
  • Lipoprotein(a)
  • Apoprotein(a)