Lipoprotein(a) levels in the Japanese population: influence of age and sex, and relation to atherosclerotic risk factors. The Jichi Medical School Cohort Study.

The authors studied the distribution of lipoprotein(a) (Lp(a)) levels with stratification for age and sex, as well as the relation between Lp(a) and atherosclerotic risk factors in a large Japanese population between 1992 and 1993. The subjects were 1,235 males and 1,762 females over 30 years old. Lp(a) was measured by an enzyme-linked immunosorbent assay. Lp(a) levels were higher in females than in males. The increase in Lp(a) with age was statistically significant, and the proportion of subjects with Lp(a) levels > 30 mg/dl also increased with age. In the obese subjects (body mass index (BMI) (kg/m2) > 26), Lp(a) levels were lower than in the non-obese subjects (BMI < or = 26) (p < 0.01 in males; p < 0.05 in females). Male alcohol drinkers had lower Lp(a) levels than nondrinkers (p < 0.05). Age, low density lipoprotein subtracting Lp(a) cholesterol [Lp(a) x 0.3], and fibrinogen level were all positively correlated with Lp(a) in both sexes. Alcohol consumption (g/day) and triglycerides were inversely correlated with Lp(a) in males, while total cholesterol subtracting Lp(a) cholesterol [Lp(a) x 0.3], high density lipoprotein, and factor VII were positively correlated in females. Multiple logistic regression analysis showed that triglycerides in males and BMI and fibrinogen in females were significant independent variables. The authors conclude that Lp(a) level is affected by various factors, such as alcohol drinking, BMI, sex, and age, and is not only correlated with lipid levels but also with hemostatic factors such as fibrinogen and factor VII.