Protein-calorie malnutrition does not predict subtle vitamin K depletion in hospitalized patients

Objective: Recent studies suggest that subtle vitamin K depletion has far-r eaching consequences. As this entity is not associated with prothrombin tim e elevation, it is important to determine whether alternate methods can hel p identify it. We investigated subtle vitamin K depletion in a hospital set ting and determined whether protein-calorie malnutrition predicts its prese nce. Design, setting, subjects: Using a high-pressure liquid chromatography (HPL C) assay of plasma phylloquinone and a food frequency questionnaire for phy lloquinone intake, we examined the phylloquinone status of 27 hospitalized patients with normal coagulation parameters, no liver disease, and no recen t warfarin use. We assessed protein-calorie nutritional status with Reilly' s criteria and anthropometrics. Results: 51% of patients (95% Cl = 31% to 70%) had evidence of subtle vitam in K depletion as defined by a subnormal plasma phylloquinone concentration . Patients whose phylloquinone intake was less than the Recommended Daily A llowance (RDA) over the preceding year had lower plasma phylloquinone conce ntrations when compared to other patients: median (range) 0.106 nmol/l (0.0 22-0.461) versus 0.301 nmol/l (0.067-3.928), respectively (P = 0.023). Plas ma phylloquinone concentrations were no different, however, between well-no urished and malnourished patients: median (range) 0.245 nmol/l (0.022-0.522 ) versus 0.188 nmol/l (0.067-3.928), respectively (P = 0.782). Conclusions: Subtle vitamin K depletion is common among hospitalized patien ts and protein-calorie malnutrition does not predict its presence.