Background—Dyslipidemias are the major cause for atherosclerosis. They may act synergistically with nonlipid risk factors to increase atherogenesis. In the present study, we examined the effects of dyslipidemias from childhood to adulthood and their interaction with nonlipid risk factors on markers of subclinical atherosclerosis.

Methods and Results—Study subjects were participants of the longitudinal Cardiovascular Risk in Young Finns Study started in 1980 (n=2265, age 3 to 18 years). To phenotype type IIa, IIb, and IV dyslipidemias and hypoHDL-cholesterolemia, we calculated age and sex-specific z scores for lipid values for each subject in 1980, 1983, 1986, and 2001. Subjects with mean z score over 90th percentile for LDL-cholesterol or triglycerides were considered having type IIa or IV dyslipidemia. Subjects with mean z score over 90th percentile for LDL-cholesterol and triglycerides had type IIb dyslipidemia, and those with mean z score below 10th percentile for HDL-cholesterol had hypoHDL-cholesterolemia. Compared to controls, subjects with type IIb dyslipidemia had increased carotid IMT (P<0.01). This difference remained significant when adjusted with other risk factors (P<0.05). Carotid IMT also increased significantly more with increasing number of nonlipid risk factors (P<0.001) or presence of the metabolic syndrome (P<0.05) in subjects with type IIb than in controls. Subjects with type IIb or type IV dyslipidemia had decreased carotid elasticity (P<0.05), but these differences became nonsignificant (P>0.3) when adjusted with blood pressure.

Conclusions—Our findings suggest that type IIb dyslipidemia has deleterious effects on vasculature already since childhood. Subjects with type IIb dyslipidemia are more vulnerable to the effects of cardiovascular risk factors and metabolic syndrome.