Mixed effects for vitamin E against respiratory infections

Vitamin E does not appear to have a beneficial effect on lower respiratory tract infections in elderly nursing home residents, but it may help them ward off upper respiratory tract infections, according to a study in the current issue of the Journal of the American Medical Association.

“Infections, particularly respiratory tract infections, are common in elderly individuals, resulting in decreased daily activity, prolonged recovery times, increased health care service use, and more frequent complications, including death,” the authors provide in background information. “In the United States, an estimated 43 percent of elderly persons will be admitted to a nursing home, with more than 85 percent of them admitted to long-term (more than one year) care facilities. Infections occur more frequently in nursing home residents than among independent-living elderly…”

Simin Nikbin Meydani, D.V.M., Ph.D., from Tufts University, Boston, and colleagues enrolled 617 persons at least 65 years old in 33 long-term care facilities from April 1998 to August 2001 to participate in a clinical trial to determine the effect of one-year of vitamin E supplementation on respiratory tract infections in elderly nursing home residents. The study participants were randomized to two groups. All participants received a multivitamin capsule with 50 percent of the recommended daily allowance (RDA) for essential micronutrients. The vitamin E group (n = 311) received a daily capsule containing 200 international units (IU) of vitamin E and the control group (n = 306) received a placebo capsule. A total of 451 participants (73 percent) completed the study.

“Vitamin E had no significant effect on incidence or number of days with infection for all, upper, or lower respiratory infections. However, fewer participants receiving vitamin E acquired one or more respiratory tract infections (60 percent vs. 68 percent for all participants; and 65 percent vs. 74 percent for completing participants), or upper respiratory tract infections (44 percent vs. 52 percent for all participants; and 50 percent vs. 62 percent for completing participants),” the authors found. In analysis the authors had not planned before conducting the study, the researchers report that “participants in the vitamin E group who completed the study had significantly fewer common colds and a 20 percent lower risk of acquiring a cold than those in the placebo group.”

“In conclusion, we found no effect of vitamin E supplementation on the incidence or duration of respiratory tract infections. However, significantly fewer vitamin E participants acquired one or more respiratory tract infections, which was more evident in URIs [upper respiratory tract infections]. Post hoc subgroup analysis among individuals completing the study revealed a significantly lower incidence of common cold and fewer participants acquiring a cold. Common colds are frequent and associated with increased morbidity in this age group, and if confirmed [in future studies], these findings suggest important implications for the well-being of the elderly.”