Posma RA, Frøslev T, Jespersen B, et al. - Researchers undertook this large observational cohort study with critically ill patients to investigate if the link between lactate levels around ICU admission and mortality was different in metformin users vs metformin nonusers. Participants included patients who got admission to ICUs in northern Denmark between January 2010 and August 2017 with any circulating lactate recorded around ICU admission (ie, 12 h before until 6 h post-admission). There were 37,293 patients in total, metformin users were 3,183 (9%). Findings revealed a strong link of early lactate levels with mortality. In metformin users vs metformin nonusers, similar lactate levels were found to be related to a lower mortality rate regardless of the degree of hyperlactataemia. Thus, experts recommended interpreting lactate levels around ICU admission according to metformin use.