Association between the results of blood test and blood PCB level of chronic Yusho patients twenty five years after the outbreak

A cross-sectional study on the association between the results of blood test and the blood concentration of PCB was conducted on the chronic Yusho patients. The subjects were 265 Yusho patients (134 men and 131 women) who received the annual nationwide health examination for Yusho in 1993. The results of the blood test and questionnaire survey at the annual health examination were used for the analyses using ANCOVA. Serum levels of triglycerides, total cholesterol, GOT, GPT, gamma-GTP, total bilirubin, and conjugated bilirubin were associated with the blood concentration of PCB adjusting for sex, age, drinking habit, smoking habit and body mass index (BMI). Because the distribution of the serum levels was strongly skewed to the right except that of serum concentration of total cholesterol, they were log transformed to approximate to the Normal distribution. The association between age and the blood concentration of PCB was significant (P < 0.001), although the associations of sex, drinking habit, smoking habit and BMI to the blood concentration of PCB were not significant. With the adjustment for sex, age, drinking habit, smoking habit and BMI, the serum concentrations of triglycerides and total cholesterol were significantly associated with the blood PCB level expressed by loge (blood concentration of PCB in ppb-1) (P = 0.02 and P < 0.001, respectively). The associations of serum levels of GOT, GPT, gamma-GTP, total bilirubin and conjugated bilirubin to the PCB level were not significant. The results of this study suggests the need of careful observation on the serum lipids of Yusho patients, especially those with high concentration of blood PCB, because the serum concentrations of total cholesterol and triglycerides are prominent risk factors of heart diseases.