Inflammation, vitamin deficiencies and organ failure in critically ill patients

Abstract

It is unknown whether biochemical vitamin deficiencies in critical illness are associated with severity of illness, organ dysfunction, inflammation or mortality. This nested cohort study recruited 98 patients admitted as emergencies to the intensive care unit, who had a stay of greater than 48 hours. Patient data were prospectively collected. Within the first 48 hours of admission, concentrations of C-reactive protein, vitamins A, E, B1, B12 and folate were measured on arterial blood. These measures were then repeated at least once during the later (>48 hours) period of their stay. Seventy patients (71%) had completed vitamin studies eligible for inclusion in the analysis. Ten patients died (14.3%) during their hospital stay and mortality was associated with age, admission source and severity of illness scores. Vitamin B12 concentration was weakly associated with C-reactive protein concentrations on admission to the intensive care unit (r on days one and two=0.4 [P=0.002], 0.36 [P=0.04], respectively) and with the Sequential Organ Failure Assessment score between days two and four (Spearman's r=0.361 [P=0.04], 0.42 [P=0.02] and 0.48 [P=0.02], respectively). Vitamin A concentration was weakly associated with the C-reactive protein concentrations on days one and five (Spearman's r=-0.5 [P=0.001], -0.4 [P=0.03], respectively). Change in deficiency status of any of the vitamins over time in the first week of intensive care admission did not appear to influence mortality. We conclude that while weak correlations were identified between vitamins A and B 12 and C-reactive protein and Sequential Organ Failure Assessment scores, the importance of these associations and their relationship to hospital mortality remain to be determined.