The Effect of a Multivitamin on the Immunologic Response to the Influenza Vaccine in the Elderly

The immunologic response to the influenza vaccine is suboptimal in the elderly. This poor response may be caused by vitamin deficiencies, which are common in the elderly. Seventy-nine subjects were randomized to receive multivitamin or placebo 100 days before influenza vaccination. Serologic analysis was done at the time of vaccination and 1 month later, using the influenza antigens used in the influenza vaccine in 1998–1999. The placebo group had a higher percentage of twofold (78% versus 56%, p = .048) and fourfold increases in titer (56% versus 35%, p = .072). The placebo group also had higher postvaccination geometric mean titers and increases in the geometric mean titer (GMT). This was statistically significant for the A/Beijing/262/95 (H1N1) antigen GMT (p = .0061) and the increase in the A/Beijing/262/95 (H1N1) antigen GMT (p = .0031). In the elderly, multivitamin use does not improve, and may decrease, the serologic response rate to the influenza vaccine.