A new study published in theJournal of Clinical Medicinefound lactate-to-albumin ratio (L/A) to predict poor prognosis and may serve as an indirect marker of hypovolemia in critically ill patients, warranting further prospective studies to evaluate its role in guiding aggressive fluid management. Previous studies have demonstrated that the L/A ratio predicts mortality among critically ill individuals. This research hypothesized that, due to the pathophysiological underpinnings, the L/A ratio might also reflect a patient’s volume status, a factor that strongly influences treatment decisions in the ICU. The current investigation sought to confirm its prognostic significance while also assessing how it correlates with hypovolemia severity. The study analyzed data from a total of 1,421 consecutive adult ICU patients. Admission L/A ratios were examined in relation to 30-day mortality as well as indirect markers of fluid balance and circulatory status. These included mean arterial pressure (MAP) at admission, median dose of norepinephrine required, and fluid intake during the first 24 hours of ICU stay. The results showed that an admission L/A ratio of ≥0.06 to be a powerful independent predictor of 30-day mortality. The patients with L/A ≥0.06 had a 42% higher risk of death when compared to those below this threshold (Hazard Ratio 1.423; 95% CI 1.183–1.712; p < 0.001). In addition to mortality prediction, the L/A ratio demonstrated moderate correlations with markers of hypovolemia where the patients with elevated L/A tended to present with reduced blood pressure at admission (r = −0.353, p < 0.001). Those with higher L/A needed more vasopressor support (r = 0.506, p < 0.001). Elevated L/A was linked to increased fluid administration during the first 24 hours (r = 0.233, p < 0.001). Also, L/A ≥0.06 was independently associated with the need for continuous renal replacement therapy (CRRT), a marker of severe organ dysfunction (Odds Ratio 2.134; 95% CI 1.652–2.757; p = 0.001). Overall, the study illuminates that L/A is not only a reliable predictor of poor prognosis but also a potential indirect marker of fluid deficits in critically ill patients. Droś, J., Świstek, R., Kasongo, P., Konieczyński, J., Bielański, P., Sajdyk, A., Wrzosek, A., Składzień, T., Depukat, R., Marusińska, M., Czech, K., Frączek, K., Paciorek, K., Skoczeń, W., Stachera, B., Chaba, W., Peszek, A., Pabian, G., Pawlik, M., … Terlecki, M. (2025). Association of the Lactate/Albumin Ratio with Mortality and Hypovolemia in Critically Ill Patients: A Retrospective Cohort Study. Journal of Clinical Medicine, 14(17), 6321.https://doi.org/10.3390/jcm14176321