BOSTON—Vitamin E supplementation may be a potential strategy to prevent respiratory tract infections (RIs) in the elderly. But the efficacy of vitamin E supplementation may depend on individual factors, including specific single nucleotide polymorphisms (SNPs) at immunoregulatory genes.
Researchers at Tufts University used data and DNA from a previous vitamin E intervention study—200 IU/d of vitamin E or a placebo for one year—in elderly nursing home residents to examine vitamin E-gene interactions for incidence of RI (Am J Clin Nutr. 2010;92: 106-114).
The effect of vitamin E on lower RI depended on sex and the SNP at IL-10 –819GA. Subjects with the least prevalent genotypes at IL-2 –330AC, IL-10 –819GA and IL-10 –1082CT had a lower incidence of RI independent of vitamin E supplementation.
The researchers concluded: “Studies that evaluate the effect of vitamin E on RIs should consider both genetic factors and sex because our results suggest that both may have a significant bearing on the efficacy of vitamin E. Furthermore, common SNPs at cytokine genes may contribute to the individual risk of RIs in the elderly."
