Lipoprotein[a] as a risk factor for preclinical atherosclerosis.
Elevated mean levels of lipoprotein[a] (Lp[a]) have been associated with symptomatic cardiovascular diseases such as clinically manifest myocardial infarction (MI), coronary artery disease, restenosis of coronary artery vein grafts after bypass, and a family history of MI. Associations of Lp[a] with arterial wall thickening in asymptomatic individuals previously have not been addressed and are evaluated in this report among participants of the Atherosclerosis Risk in Communities (ARIC) Study. Intima-media wall thickening in the extracranial carotid arteries was assessed noninvasively with B-mode ultrasonography; Lp[a] was measured as its total protein component. Individuals with wall thickening > or = 90th percentile of the population maximum far-wall thickness were pair matched to participants < 75th percentile of wall thickness by race, gender, center, 10-year age group, and time of examination. These selection criteria yielded 492 matched pairs, with 395 white pairs and 97 black pairs. The mean Lp[a] protein level for all black participants was 174.6 micrograms/mL compared with 77.8 micrograms/mL for whites. Conditional logistic regression analysis for the association of Lp[a] with case-control status yielded a statistically significant prevalence odds ratio (OR) estimate of 1.49, based on a 1-SD difference in Lp[a] protein, after adjusting for age, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, fibrinogen, hypertension, and cigarette smoking. None of these risk factors significantly altered the OR, in agreement with reports that Lp[a] is unaffected by environmental influences. In addition, no differential effect of Lp[a] protein on case-control status (effect modification) was observed by race, gender, low-density lipoprotein cholesterol, or fibrinogen in this population.(ABSTRACT TRUNCATED AT 250 WORDS)
Schreiner
P J
PJ
Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27599.
Morrisett
J D
JD
Sharrett
A R
AR
Patsch
W
W
Tyroler
H A
HA
Wu
K
K
Heiss
G
G
D001161:Arteriosclerosis / Q000453:epidemiology / Q000378:metabolism*; D044383:Black People; D002339:Carotid Arteries / Q000737:chemistry; D008078:Cholesterol, LDL / Q000097:blood; D005260:Female; D006801:Humans; D017270:Lipoprotein(a) / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D044465:White People
D008078:Cholesterol, LDL; D017270:Lipoprotein(a)