Vitamin A and respiratory syncytial virus infection. Serum levels and supplementation trial

Abstract

Objective: To determine the benefit of oral vitamin A supplementation for acute respiratory syncytial virus (RSV) infection.

Design: An observational study of vitamin A and retinol binding protein (RBP) levels in RSV-infected inpatients and two control groups; and a randomized, controlled trial of vitamin A supplementation for RSV-infected inpatients.

Setting: Two tertiary care, urban teaching hospitals.

Participants: Thirty-two RSV-infected inpatients (aged 2 to 58 months), 35 hospitalized children without respiratory infections (aged 2 to 19 months), and 39 healthy outpatient controls (aged 2 to 67 months).

Intervention: The RSV-infected group was randomized to receive a single dose of 100,000 IU oral vitamin A or placebo.

Main outcome measures: Serum vitamin A and RBP levels of all participants and clinical indicators of severity such as days of hospitalization, oxygen use, intensive care, intubation, and a daily severity score.

Results: Mean vitamin a and RBP levels were lower in RSV-infected children than in healthy controls (P > .05). Among RSV-infected children, those admitted to the intensive care unit had lower mean vitamin A (P = .03) and RBP levels (P = .04) than those not in intensive care. Among children hospitalized without respiratory infection, those admitted to the intensive care unit had lower mean vitamin A levels (P = .02) than those not in intensive care. In the RSV-infected children, no significant difference was seen between the vitamin A group (n = 21) and the placebo group (n = 11) in improvement in severity score, mean days of hospitalization, intensive care, or receipt of supplemental oxygen.

Conclusions: Serum vitamin A and RBP levels were low in children hospitalized with RSV infection and were lower in children admitted to the intensive care unit. Hospitalized control patients in intensive care also had lower levels than those treated on the ward. We observed no benefit from oral vitamin A supplementation for children hospitalized with RSV infection.