title: A strong secular trend in serum gamma-glutamyltransferase from 1996 to 2003 among South Korean men.
abstract: Serum gamma-glutamyltransferase (GGT) concentration, within its normal range, has recently been proposed as a reliable marker of oxidative stress. Oxidative stress plays a central pathogenic role in many metabolic and/or cardiovascular diseases, incidences of which have recently increased in South Korea. Since serum GGT has strong associations with these diseases and their risk factors, the authors hypothesized a corresponding secular trend of increasing serum GGT levels in South Korea. Study subjects were 8,072 male workers at a large steel company who were aged 24-44 years at baseline and had received annual physical examinations from 1996 to 2003. The secular trend was a 0.1066-units/liter increase in ln(GGT) level per calendar year (a 180% increase during the 7-year follow-up period) (p < 0.01). Adjustment for body mass index, alcohol consumption, smoking, exercise, and cholesterol level as time-dependent covariates did not change the results. Although cholesterol is commonly used as a marker of epidemiologic transition, there was a less dramatic secular trend in ln(serum cholesterol) level, and it disappeared after adjustment for the secular trend in serum GGT. These findings suggest that serum GGT concentration can be used as a sensitive marker of epidemiologic transition, and they portend a continuing rise in incidences of metabolic and/or cardiovascular diseases in this population in the coming years.
authors.affiliation: Department of Preventive Medicine and Health Promotion Research Center, School of Medicine, Kyungpook National University, Daegu, South Korea. lee_dh@knu.ac.kr
authors.forename: Duk-Hee
authors.initials: DH
authors.lastname: Lee
authors.forename: Myung-Hwa
authors.initials: MH
authors.lastname: Ha
authors.forename: Sin
authors.initials: S
authors.lastname: Kam
authors.forename: Byungyeol
authors.initials: B
authors.lastname: Chun
authors.forename: Jangkyu
authors.initials: J
authors.lastname: Lee
authors.forename: Kyungeun
authors.initials: K
authors.lastname: Song
authors.forename: Yongchool
authors.initials: Y
authors.lastname: Boo
authors.forename: Lyn
authors.initials: L
authors.lastname: Steffen
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
mesh_terms: D000328:Adult; D000367:Age Factors; D000410:Alanine Transaminase / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002784:Cholesterol / Q000097:blood; D006801:Humans; D007221:Industry; D007723:Korea; D008297:Male; D018384:Oxidative Stress; D011446:Prospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D013232:Steel; D013997:Time Factors; D005723:gamma-Glutamyltransferase / Q000097:blood*
chemical_list: D015415:Biomarkers; D013232:Steel; D002784:Cholesterol; D005723:gamma-Glutamyltransferase; D000410:Alanine Transaminase