Gamma-glutamyltransferase is associated with cardiovascular and all-cause mortality: a meta-analysis of prospective cohort studies Moderate Liver Function (GGT)Meta-analysisObservational evidence Meta-analysis Highest vs lowest GGT quartile associated with 56% higher all-cause mortality (pooled RR 1.56, 95% CI 1.34–1.83) across 7 prospective cohorts, 273,141 participants Causal status: Associational; proposed independent of alcohol intake but mechanism as a general oxidative-stress/liver marker not fully causal Reliability / bias notes: GGT is nonspecific (affected by alcohol, medications, fatty liver); Asian subgroup result not significant Du et al · Prev Med · 2013 · PMID 23571185 Read the study →