Upper Limits of Normal for Serum Alanine Aminotransferase Levels in Chinese Han Population

et al. (2012) Upper Limits of Normal for Serum Alanine Aminotransferase Levels in Chinese Han Population. PLoS ONE 7(9): e43736. doi:10.1371/journal.pone.0043736 Upper Limits of Normal for Serum Alanine Aminotransferase Levels in Chinese Han Population Ping Chen 0 Ming-Hua Zheng 0 Ke-Qing Shi 0 Yu-Chen Fan 0 Wen-Yue Liu 0 Xian-Feng Lin 0 Ling-Fei Li 0 Yong- 0 Man-Fung Yuen, The University of Hong Kong, Hong Kong 0 1 Department of Infection and Liver Diseases, Liver Research Center, the First Affiliated Hospital of Wenzhou Medical College , Wenzhou , China , 2 Institute of Hepatology, Wenzhou Medical College , Wenzhou , China , 3 Department of Hepatology, Qilu Hospital of Shandong University , Jinan , China , 4 School of the First Clinical Medical Sciences, Wenzhou Medical College , Wenzhou , China Background and Objectives: Serum alanine aminotransferase (ALT) activity is the most common tool for the assessment of liver diseases. However, it is not clear whether the current normal ALT range really discriminate patients with or without liver diseases. The present study was to establish a new normal range of ALT and examine its ability to identify patients with hepatitis B or nonalcoholic fatty liver disease (NAFLD) in Chinese Han population. Methods: 53037 adults were included in this study from January 1st 2008 to August 31st 2010. The 95th percentile of ALT in population with relative low risk factors for liver diseases was set as the new upper limits of normal ALT in gender-specific manner. Results: The 95th percentile levels at low risk factors for liver diseases were achieved at 35 U/L for men and 23 U/L for women. The concordance statistics for detection were 0.873 (95%CI: 0.865-0.881) for HBV and 0.932 (95%CI: 0.927-0.937) for NAFLD in men while 0.857 (95%CI: 0.850-0.864) for HBV and 0.909 (95%CI: 0.903-0.915) for NAFLD in women. The median sensitivity of the current used ALT upper limit (40 U/L) was 6.6% for HBV and 29.7% for NAFLD and median specificity was 98.7% for men and 99.4% for women. Using our new-derived thresholds, the sensitivities ranged from 35.3% to 61.1% and the specificities were 94.8% for men and 94.6% for women. Conclusions: Our results suggest that upper limits of ALT 35 U/L for men and 23 U/L for women in Chinese Han population. Re-consideration of normal limits of ALT should be recommended. Trial Registration: ChiCTR.org ChiCTR-OCS-11001173 PLOS ONE | www.plosone.org - Funding: This work was supported by grants from National Science and Technology Major Project of China (2012ZX10002004), Scientific Research Foundation of Wenzhou, Zhejiang Province, China (H20090014, Y20090269), Health Bureau of Zhejiang Province (2010KYB070), Research Foundation of Education Bureau of Zhejiang Province (Y201009942) and Project of New Century 551 Talent Nurturing in Wenzhou. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing Interests: The authors have declared that no competing interests exist. Serum alanine aminotransferase (ALT) concentration is the most widely used tool for the assessment of liver diseases. Upper limit of normal (ULN) ALT is usually the reliable candidate to discriminate normal or abnormal for liver function. Particularly, in the treatment of viral hepatitis, ALT is always used for screening the subjects who need anti-viral therapy [1,2,3]. However, it is still not well demonstrated whether the current used ULN standard of ALT is appropriate for clinical events. Current ULN for ALT level were set, on average, ranging from 30 U/L to 50 U/L over the past 10 years. Such thresholds, however, vary tremendously among hospitals, research centers and geographic locations. Currently, the upper limit of normal ALT has been re-evaluated in different countries by involving different age groups. These studies suggested that the upper limit of normal ALT should be revised and the recommendations are 30 U/L for men and 19 U/L for women respectively [4,5,6,7]. In China, the upper limit of normal ALT was established in the 1950s and has not changed in the past four decades [8]. Since Chinese population has a high background of hepatitis B surface antigen (HBsAg) prevalence [9,10], and at the same time there are dramatic increases in nonalcoholic fatty liver diseases (NAFLD) due to rapid change in lifestyle of Chinese [1,11], it is urgent to establish the upper limit of normal ALT for adult population in China. In the present study, we established a new normal range of serum ALT and examined its ability to identify patients with hepatitis B and nonalcoholic fatty liver disease (NAFLD) and those at low risks for liver diseases in Chinese Han population. Pseudoephedrine hydrochloride Materials and Methods Study population A prospective cross-sectional study was conducted among healthy examination participants at the First Affiliated Hospital of Wenzhou Medical College from January 1st 2008 to August 3 (...truncated)