Testing the feasibility and initial effects of iron and vitamin C to enhance nursing home residents' immune status following an influenza vaccine

Influenza infections pose a serious threat to residents living in nursing homes and are a major cause of morbidity and mortality in older adults. It is estimated that influenza vaccination is only 30%–40% effective in the frail elderly. This 2-group experimental design study examined the efficacy of giving iron supplements to nursing home residents aged 65 and older to improve immune response following influenza vaccination. Specific aims of the study were to test study procedures and explore initial immune response. A number of barriers were encountered during the recruitment and consent phase limiting subject recruitment. Only serum transferrin was significantly different following the 30-day administration of iron supplementation. It was concluded that to achieve sufficient power to examine the effect of the intervention on immune response and infection rates, aggressive recruiting strategies at multiple sites are necessary.