A cost-utility analysis of multivitamin and multimineral supplements in men and women aged 65 years and over.

BACKGROUND & AIMS As people age there is a progressive dysregulation of the immune system that may lead to an increased risk of infections, which may precipitate hospital admission in people with chronic heart or respiratory diseases. Mineral and vitamin supplementation in older people could therefore influence infections in older people. However, the evidence from the available randomised controlled trials (RCTs) is mixed. The aim of the study was to assess the relative efficiency of multivitamin and multimineral supplementation compared with no supplementation. METHODS Cost-utility analysis alongside an RCT. Participants aged 65 years or over from six general practices in Grampian, Scotland, were studied. They were randomised to one tablet daily of either a multivitamin and multimineral supplement or matching placebo. Exclusion criteria were use of mineral, vitamin or fish oil supplements in the previous 3 months (1 month for water soluble vitamins), vitamin B12 injection in the last 3 months. RESULTS Nine hundred and ten participants were recruited (454 placebo and 456 supplementation). Use of health service resources and costs were similar between the two groups. The supplementation arm was more costly although this was not statistically significant ( pound15 per person, 95% CI-3.75 to 34.95). After adjusting for minimisation and baseline EQ-5D scores supplementation was associated with fewer QALYs per person (-0.018, 95% CI-0.04 to 0.002). It was highly unlikely that supplementation would be considered cost effective. CONCLUSIONS The evidence from this study suggests that it is highly unlikely that supplementation could be considered cost effective.