Author Description

This dissertation, "Smoking and Liver Enzymes in Older Chinese Men: the Guangzhou Biobank Cohort Study (GBCS)" by Shan, Luo,, was obtained from The University of Hong Kong (Pokfulam, Hong Kong) and is being sold pursuant to Creative Commons: Attribution 3.0 Hong Kong License. The content of this dissertation has not been altered in any way. We have altered the formatting in order to facilitate the ease of printing and reading of the dissertation. All rights not granted by the above license are retained by the author. Abstract: Objective: To examine the association between smoking and common liver enzymes (Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyl transferase (GGT)) among older Chinese men aged 50 or above. Design: Cross-sectional study based on Guangzhou Biobank Cohort Study Setting: Guangzhou, China. Subjects: 2049 Guangzhou older men in the Guangzhou Biobank Cohort Study who were free of clinical indications of liver diseases. Methods: Information on cigarette smoking and potential confounding variables were collected by standardized interviews and laboratory assays. Elevation of liver enzymes was defined as >40 U/L for ALT, >40 U/L for AST and >50 U/L for GGT. Both logistic regression and linear regression modeling were used to estimate the association of cigarette smoking with liver enzymes, adjusted for age, education, personal income, body mass index (BMI), physical activity and alcohol drinking. Results: Current smoking was positively associated with elevated GGT. Compared to never smokers, the adjusted odds ratios (OR) [95% confidence interval] of elevated GGT was 1.58 [1.06-2.35] and 1.68 [1.18-2.41] for those who smoked >=20 cigarettes/day and >=20 pack-years, respectively, while the adjusted OR for those who smoked =40 years was 1.57 [1.06-2.33] and 1.38 [0.92-2.08], respectively. The interaction effect of smoking and BMI was significant for elevated ALT and GGT (both P0.05). The risk of e