Clinical Characteristics of Factory Wokers with Asymptomatic Liver Function Test Abnormalities in Serial Health Examination

연속적으로 시행한 공장 근로자 건강 검진에서 무증상 간기능 검사 이상자의 임상적 특성

Background/Aims The liver funtion tests(LFTs), such as aspartate aminotransferase(AST), alanine amino-transferase(ALT), r -glutamyl transferase( r -GT), have been widely used for screening tests but their low positive predictive value can cause many false positive results. To evaluate the clinical usefulness of these tests, we analyzed serial LFT results of single factory workers and compared the risk factor's in groups divided by the serial LFT results. Methods From June 2001 to October 2001, 1223 consecutive healthy workers in a single factory were enrolled and questionnaire, LFT and liver ultrasonography were performed. Previous LFT results were collected from Annual Health Examination Survey. According to the abnormalities in serial LFT, participants were classified into three groups (abnormal-in-both, alternating normal-in-both) and the risk factors were compared among these groups using multiple logistic regression Results The prevalence of LFT abnormality in a single test was 16.8% but, in serial LFT, only 5% of participants showed consistent abnormality. The risk factors for abnormal-in-both group, compared with alternating group, were liver ultrasonography abnormality such as fatty liver(odds ratio, 2.2; p=0.026) and heavy alcohol intake (more than 210g/week) (odds ratio, 7.2;P=0.064). HBsAg was not significant risk factor for any of the three groups. ConclusionIn factory workers with serial LFT abnormality, alcoholic liver disease could be the principal cause of abnormal LFT. Even if HBsAg were positive in patients with abnormal LFT, there is a possibility of another causes for LFT abnormalities such as alcoholic liver disease and nonalcoholic steatosis or steatohepatitis