Prospective investigation of serum metabolites, coffee drinking, liver cancer incidence, and liver disease mortality.

Coffee has been consistently associated with lower risk of liver cancer and chronic liver disease, suggesting that coffee affects mechanisms underlying disease development.We measured serum metabolites using untargeted metabolomics in 1:1 matched nested case-control studies of liver cancer (n = 221 cases) and fatal liver disease (n = 242 cases) in the ATBC cohort (N = 29,133). Associations between baseline coffee drinking and metabolites were identified using linear regression; conditional logistic regression models were used to identify associations with subsequent outcomes.Overall, 21 metabolites were associated with coffee drinking and also each subsequent endpoint; nine metabolites and trigonelline, a known coffee biomarker, were identified. Tyrosine and two bile acids, glycochenodeoxycholic acid (GCDCA) and glycocholic acid (GCA), were inversely associated with coffee but positively associated with both outcomes; odds ratios (ORs) comparing the 90th to 10th percentile (modeled on a continuous basis) ranged from 3.93 (95% CI = 2.00-7.74) for tyrosine to 4.95 (95% CI = 2.64-9.29) for GCA and from 4.00 (95% CI = 2.42-6.62) for GCA to 6.77 (95% CI = 3.62-12.65) for GCDCA for liver cancer and fatal liver disease, respectively. The remaining six metabolites and trigonelline were positively associated with coffee drinking but inversely associated with both outcomes; ORs ranged from 0.16 to 0.37. Associations persisted following diet-adjustment and for outcomes occurring >10 years after blood collection.A broad range of compounds were associated with coffee drinking, incident liver cancer and liver disease death over 27 years of follow-up. These associations provide novel insight into chronic liver disease and liver cancer etiology and support a possible hepatoprotective effect of coffee.