BACKGROUND: High serum alanine aminotransferase (ALT) levels have been associated with increased risk of diabetes and with increased mortality, but associations of variations of ALT in the normal range with outcomes have been less well studied. METHODS: We studied the relationship between ALT, mortality and cardiovascular events in the West of Scotland Coronary Prevention Study (WOSCOPS) and the Prospective Study of Pravastatin in the Elderly at Risk (PROSPER) trials that explicitly excluded subjects with clinically significant liver damage, plus the Leiden 85-plus, a study of survivors to age 85 years. The associations between ALT and morbidity and mortality outcomes were investigated using Cox proportional hazard models adjusting for a comprehensive panel of cardiovascular risk factors. RESULTS: In all three study cohorts, ALT displayed an independent inverse relationship with all-cause mortality so that hazard ratios for fourth versus first quarter of ALT were all below 1.0; HRs 0.64 [95% confidence interval (CI) 0.50-0.81], 0.86 (0.73-1.01), 0.66 (0.50-0.87); WOSCOPS, PROSPER, Leiden 85-plus, respectively. In WOSCOPS and PROSPER, ALT was also inversely associated with risk of fatal plus non-fatal cardiovascular events, including coronary heart disease (CHD) events and stroke. CONCLUSIONS: In three independent populations, ALT in the normal range displayed an inverse relationship with total mortality, cardiovascular events and non-cardiovascular events in middle-to-older aged subjects without evidence of clinically significant liver damage, independent of traditional cardiovascular and other risk factors. These findings indicate that the relationship between ALT and clinical outcomes is more complex than generally appreciated.

Original publication

DOI

10.1093/ije/dyr172

Type

Journal article

Journal

Int J Epidemiol

Publication Date

12/2011

Volume

40

Pages

1530 - 1538

Keywords

Age Factors, Aged, Aged, 80 and over, Alanine Transaminase, Anticholesteremic Agents, Blood Pressure, Cardiovascular Diseases, Female, Humans, Lipids, Male, Middle Aged, Proportional Hazards Models, Prospective Studies, Randomized Controlled Trials as Topic, Risk Factors, Smoking