Significantly elevated phosphatidylethanol levels in recent suicide attempters, but not in depressed controls and healthy volunteers

•Phosphatidylethanol (PEth) levels are significantly increased in psychiatric patients compared with controls.•PEth levels in suicide attempters was the highest and significantly higher than in patients with major depressive disorders.•There was a discrepancy between self-reported chronic alcohol use and objectively measured alcohol use in suicide attempters.•Low grade inflammation was implicated in the PEth association with suicide attempt and major depressive disorder.•PEth levels predicted depression and suicidality scores only in suicide attempter group.