Riboflavin Status in Acutely Ill Patients and Response to Dietary Supplements

Background: Although a number of studies have reported riboflavin deficiency in free‐living older people, no data are available on riboflavin intake and status in older people during acute illness. Methods: To determine the riboflavin response to dietary supplements during acute illness, 297 hospitalized, acutely ill older patients are randomly assigned to receive a daily oral nutritional supplement containing 1.3 mg of riboflavin or a placebo for 6 weeks. Outcome measures are riboflavin intake and riboflavin biochemical status at baseline, 6 weeks, and 6 months using the erythrocyte glutathione reductase activation coefficient (EGRAC), a measure of riboflavin tissue saturation. EGRAC values are inversely proportional to riboflavin status. Results: Fifty‐six percent of patients (167/297) have suboptimal riboflavin status (EGRAC > 1.30). No significant correlation is found between EGRAC and either total energy or riboflavin intakes. Significant correlations are found between total energy intake and riboflavin intakes both in hospital and at home (r = 0.67, P < .0001 and r = 0.57, P < .0001, respectively). Smokers and patients with chronic obstructive pulmonary disease (COPD) have lower riboflavin status (high EGRAC values) compared with nonsmokers and those without COPD. Riboflavin status improves significantly in the supplement group at 6 weeks compared with the placebo group, but status declines between 6 weeks and 6 months, after patients stop taking the supplements. Conclusions: A high proportion of acutely ill patients have suboptimal riboflavin status. Supplementation with a physiological amount of riboflavin in a mixed‐nutrient supplement significantly improves riboflavin status, but the effect is transient and status deteriorates again after patients stop taking the supplements.