Metabolic origin of hypovitaminosis C in acutely hospitalized patients.

OBJECTIVE: Recent studies have indicated a high prevalence of hypovitaminosis C in acutely hospitalized patients. It is unclear whether hypovitaminosis C in this setting represents deficiency or tissue redistribution of the vitamin as part of the acute-phase response.
METHODS: We administered vitamin C for 1 wk to acutely hospitalized, but not critically ill patients with hypovitaminosis C, on the assumption that a large increase in plasma and mononuclear leukocyte vitamin C concentrations, a decrease in metabolic markers of oxidative stress, or an improvement in psychologic mood state would implicate the initial condition as nutritional deficiency rather than tissue redistribution.
RESULTS: Vitamin C administration increased plasma and mononuclear leukocyte vitamin C concentrations from subnormal (16.3 ± 12.4 μmol/L and 6.5 ± 5.5 mmol/L, respectively) to normal (71.0 ± 30.9 μmol/L, P < 0.0001, and 8.2 ± 6.8 mmol/L, P < 0.015); the mood disturbance score improved by 33% (P < 0.008). There was no increase in plasma glutathione concentrations or a reduction in plasma or mononuclear leukocyte malondialdehyde concentrations. An inverse relation was observed between plasma C-reactive protein and plasma vitamin C concentrations (P = 0.006).
CONCLUSION: Although associated with systemic inflammation, the metabolic features of hypovitaminosis C in acutely hospitalized, non-critically ill patients are more consistent with deficiency than with tissue redistribution.