Serum melatonin levels during the first seven days of severe sepsis diagnosis are associated with sepsis severity and mortality

Abstract

ObjectiveHigher serum melatonin levels have previously been found in patients with severe sepsis who died within 30 days of diagnosis than in survivors. The objective of our study were to determine whether serum melatonin levels during the first seven days of severe sepsis diagnosis could be associated with sepsis severity and mortality. MethodsMulticentre study in eight Spanish Intensive Care Units which enrolled 308 patients with severe sepsis. We determined serum levels of melatonin, malondialdehyde (as biomarker of lipid peroxidation) and tumor necrosis factor-alpha at days 1, 4 and 8 of severe sepsis diagnosis. The study's primary endpoint was 30-day mortality. ResultsA total of 103 patients had died and 205 survived at 30 days of severe sepsis diagnosis, with the non-survivors presenting higher serum melatonin levels at days 1 (p<0.001), 4 (p<0.001) and 8 (p<0.001) of severe sepsis diagnosis than the survivor patient group. The multiple logistic regression analysis found that serum melatonin levels at days 1, 4 and 8 of severe sepsis diagnosis (p<0.001, p=0.01 and p=0.001, respectively) were associated with mortality adjusted for age, serum lactic acid, SOFA score and diabetes mellitus. ConclusionsThe novel and more interesting findings of our study were that serum melatonin levels during the first seven days of severe sepsis diagnosis are associated with sepsis severity and mortality.