Total plasma fatty acids were measured in 101 cirrhotic inpatients (64 men, 37 women, aged 64.3 +/- 1.2 (SEM) yr; range, 34-80) who were subsequently followed for survival for a mean of 14.8 +/- 1.0 months. Data on plasma fatty acids have been published elsewhere. Individual values of these variables were categorized in a binary fashion using the 5th or the 95th percentiles of a group of 44 well-nourished healthy controls (24 men, 20 women, aged 51.3 +/- 2.1 yr; range, 32-76) as the cutoff limit. Forty-nine patients died during follow-up (2-yr cumulative probability of survival, 52%). Deficiency of palmitate, dihomo-tau-linolenate, and arachidonate (values below the 5th percentile) were univariately associated with death (long-rank test). However, after a multivariate analysis (Cox's proportional hazards regression), only the existence of plasma arachidonate deficiency was included in the final model (beta, 0.62; relative risk, 1.86; 95% CI, 1.06-3.25; p < 0.05). We conclude that arachidonic acid deficiency significantly increases the mortality risk in patients with advanced liver cirrhosis.