Interaction of age with lipoproteins as predictors of aortic valve calcification in the multi-ethnic study of atherosclerosis.
BACKGROUND
Previous epidemiologic studies have shown that low-density lipoprotein is an independent risk factor for prevalent aortic valve calcification (AVC); however, to our knowledge, the interactions between plasma lipoprotein concentrations and age on the relative risks (RRs) for AVC prevalence and severity have not been examined in a large, racially and ethnically diverse cohort.


METHODS
Using stepwise RR regression, the relationships of baseline fasting lipid levels and lipoprotein levels to baseline prevalence and severity of AVC were determined in 5801 non-statin-using participants in the Multi-Ethnic Study of Atherosclerosis (MESA).


RESULTS
In age-stratified, adjusted analyses, the low-density lipoprotein-associated RRs (95% confidence intervals) for prevalent AVC were higher for younger compared with older participants (age 45-54 years, 1.69 [1.19-2.39]; age 55-64 years, 1.48 [1.24-1.76]; age 65-74 years, 1.09 [0.95-1.25]; and age 75-84 years, 1.16 [0.99-1.36]; P interaction = .04]. There was a similar, significant interaction of age with total cholesterol-associated RR for prevalent AVC (P interaction = .04). In contrast, total- to high-density lipoprotein cholesterol ratio RRs were similar across all age strata (P interaction = .68). At multivariate analyses, no lipoprotein parameter was associated with AVC severity.


CONCLUSIONS
In this racially and ethnically diverse, preclinical cohort, low-density lipoprotein was a risk factor for AVC only in participants younger than 65 years, whereas the total cholesterol/high-density lipoprotein cholesterol ratio was associated with a modest increased risk of AVC across all ages. These findings may have important implications for the efficacy of and targets for dyslipidemia therapies in calcific aortic valve disease.
Division of Cardiology, Department of Internal Medicine, University of Washington, 1959 NE Pacific St, Seattle, WA 98195-6422, USA.
David S
DS
Owens
Ronit
R
Katz
Eric
E
Johnson
David M
DM
Shavelle
Jeffrey L
JL
Probstfield
Junichiro
J
Takasu
John R
JR
Crouse
J Jeffrey
JJ
Carr
Richard
R
Kronmal
Matthew J
MJ
Budoff
Kevin D
KD
O'Brien
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D001024:Aortic Valve Stenosis / Q000097:blood* / Q000453:epidemiology / Q000208:ethnology; D050197:Atherosclerosis / Q000097:blood* / Q000453:epidemiology / Q000208:ethnology; D002114:Calcinosis / Q000097:blood* / Q000453:epidemiology / Q000208:ethnology; D016009:Chi-Square Distribution; D008078:Cholesterol, LDL / Q000097:blood*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D012044:Regression Analysis; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology
D008078:Cholesterol, LDL