Antioxidant vitamins E and C as adjunct therapy of severe acute lower-respiratory infection in infants and young children: a randomized controlled trial

Objective: To evaluate the effect of antioxidant Vitamins E and C as adjunct therapy of severe acute lower respiratory infection (ALRI) in children. Design: Randomized double-blind placebo-controlled clinical trial. Setting: A large childrens' hospital serving the urban poor in Kolkata, India. Subjects: Children aged 2-35 months admitted with severe ALRI. Intervention: In total, 174 children were randomly assigned to receive alpha-tocopherol 200mg and ascorbic acid 100mg twice daily or placebo for 5 days. All children received standard treatment for severe ALRI. Outcome measures were: time taken to recover from a very ill status, fever, tachypnoea, and feeding difficulty; and improvement in oxidative stress and immune response indicated by thiobarbituric acid reacting substances (TBARS) and response to skin antigens, respectively. Results: Recovery rate ratios (95% CI) using proportional hazards model were 0.89 (0.64-1.25), 1.01(0.72-1.41), 0.86(0.57-1.29), and 1.12(0.77-1.64) for very ill status, feeding difficulty, fever, and tachypnoea, respectively. TBARS values were high and similar in the two groups at admission, discharge, and at 2 weeks follow-up. Serum alpha-tocopherol significantly increased in treated group at discharge. Immune response to skin antigens were very poor at admission and after 2 weeks, in both groups. Conclusion: Infants with severe ALRI failed to benefit from two antioxidant nutrients as adjunct therapy. Severe ALRI in infants may cause cell-mediated immune dysfunction. We need a better understanding of oxidative processes in growing infants to help us better design interventions with antioxidant therapy.