Independent and interactive effects of apolipoprotein E phenotype and cardiorespiratory fitness on plasma lipids.
OBJECTIVE
To examine whether the association Apolipoprotein E (Apo E) phenotype with plasma lipids is influenced by physical fitness level. Also, to explore the interactive and independent relative contributions of Apo E phenotype, fitness (or physical activity), and other modifiable factors to variation in plasma low density lipoprotein (LDL-C) and high density lipoprotein (HDL-C) levels at baseline and over a seven-year follow-up.


METHODS
Physical fitness (duration of a graded treadmill test), Apo E phenotype, plasma LDL-C and HDL-C, and covariates were measured at baseline and seven years later in a bi-racial cohort of young adults, aged 18-30 years at baseline in 1985-86, from the Coronary Artery Risk Development In Young Adults (CARDIA) study.


RESULTS
Fitness did not influence the associations of Apo E and LDL-C or HDL-C. The independent effects of several modifiable variables (changes in Keys' score, smoking, oral contraceptive use, education, body weight, alcohol intake, and fitness), when combined, contributed considerably more than Apo E to the variance in LDL-C changes (6.74% or 8.71% for combined modifiable variables vs. 1.27% or 0.90% for ApoE, in women or men, respectively) and HDL-C changes (13.11% or 12.66% for combined modifiable variables vs. 0.12% or 0.02% for ApoE, in women or men, respectively). The pattern of findings was similar when self-reported physical activity was substituted for fitness.


CONCLUSIONS
Changes in modifiable factors, including fitness, may be stronger correlates of changes in LDL-C and HDL-C over time than the immutable factor, Apo E phenotype.
Schmitz
K H
KH
Division of Epidemiology, Minneapolis, MN 55454, USA.
Schreiner
P J
PJ
Jacobs
D R
DR
Leon
A S
AS
Liu
K
K
Howard
B
B
Sternfeld
B
B
D000293:Adolescent; D000328:Adult; D001057:Apolipoproteins E / Q000097:blood*; D002318:Cardiovascular Diseases / Q000209:etiology; D002320:Cardiovascular Physiological Phenomena; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D015444:Exercise / Q000502:physiology; D005260:Female; D006801:Humans; D008055:Lipids / Q000097:blood*; D008297:Male; D010641:Phenotype; D010809:Physical Fitness / Q000502:physiology*; D012143:Respiratory Physiological Phenomena; D012307:Risk Factors
D001057:Apolipoproteins E; D008055:Lipids