The effect of age and lifestyle factors on plasma levels of apolipoprotein E.
BACKGROUND
The plasma concentration of apolipoprotein E might be an important risk factor for various chronic diseases, including coronary heart disease.


OBJECTIVE
To investigate the role of lifestyle-related factors in determining concentrations of apolipoprotein E.


METHODS
The independent effects of age and several lifestyle-related factors [body mass index (BMI), smoking, consumption of alcohol, physical activity, educational level and poly-unsaturated:saturated fatty acid intake ratio in diet] on the apolipoprotein E concentration were assessed for a sample of 757 middle-aged working men. Multiple log-linear regression models were fitted with additional correction for the apolipoprotein E polymorphism.


RESULTS
The overall mean plasma concentration of apolipoprotein E was 3.44 mg/dl with mean levels varying from 2.42 mg/dl in men with the E4/4 phenotype to 8.32 mg/dl in men in the E2/2 group. In multivariate analysis apolipoprotein E levels were found to be significantly positively correlated to BMI (P<0.0001) and consumption of alcohol (P=0.04). The effect of age on the apolipoprotein E concentration was significantly quadratic (P=0.02) with highest levels found in the men aged 40-44 years (levels 13.3% greater than those in the men aged 35-39 years). Subjects with BMI in the range 27-30 kg/m2 had on average a 16.4% higher apolipoprotein E concentration than did men in the group with BMI lower than 23 kg/m2. This adjusted proportional increase amounted to 22.6% for the severely obese subjects (BMI>30 kg/m2). The independent effect of current smoking was only of borderline stat stical significance.


CONCLUSIONS
These results indicate that age and lifestyle-related factors, such as BMI and to a lesser extent consumption of alcohol and smoking, should be taken into account as possible confounders in the study of the plasma concentration of apolipoprotein E as a risk factor for coronary heart disease.
Braeckman
L
L
Department of Public Health, University of Gent, Belgium. lutgart.braeckman@rug.ac.be
De Bacquer
D
D
Rosseneu
M
M
De Backer
G
G
D000328:Adult; D000367:Age Factors; D000428:Alcohol Drinking; D001057:Apolipoproteins E / Q000097:blood*; D015992:Body Mass Index; D004041:Dietary Fats / Q000008:administration & dosage; D004522:Educational Status; D015444:Exercise; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D012907:Smoking
D001057:Apolipoproteins E; D004041:Dietary Fats