title: Cost-effectiveness of vitamin D supplementation and exercise in preventing injurious falls among older home-dwelling women: findings from an RCT.
abstract: This study assessed the cost-effectiveness of vitamin D supplementation and exercise, separately and combined, in preventing medically attended injurious falls among older home-dwelling Finnish women. Given a willingness to pay of €3,000 per injurious fall prevented, the exercise intervention had an 86 % probability of being cost-effective in this population.
  
  
  BACKGROUND
  The costs of falling in older persons are high, both to the individual and to society. Both vitamin D and exercise have been suggested to reduce the risk of falls. This study assessed the cost-effectiveness of vitamin D supplementation and exercise, separately and combined, in preventing medically attended injurious falls among older Finnish women.
  
  
  METHODS
  Economic evaluation was based on the results of a previously published 2-year randomized controlled trial (RCT) where 409 community-dwelling women aged 70 to 80 years were recruited into four groups: (1) no exercise + placebo (D-Ex-), (2) no exercise + vitamin D 800 IU/day (D+Ex-), (3) exercise + placebo (D-Ex+), and (4) exercise + vitamin D 800 IU/day (D+Ex+). The outcomes were medically attended injurious falls and fall-related health care utilization costs over the intervention period, the latter evaluated from a societal perspective based on 2011 unit costs. Incremental cost-effectiveness ratios (ICER) were calculated for the number of injurious falls per person-year prevented and uncertainty estimated using bootstrapping.
  
  
  RESULTS
  Incidence rate ratios (95 % CI) for medically attended injurious falls were lower in both Ex+ groups compared with D-Ex-: 0.46 (0.22 to 0.95) for D-Ex+, 0.38 (0.17 to 0.81) for D+Ex+. Step-wise calculation of ICERs resulted in exclusion of D+Ex- as more expensive and less effective. Recalculated ICERs were €221 for D-Ex-, €708 for D-Ex+, and €3,820 for D+Ex+; bootstrapping indicated 93 % probability that each injurious fall avoided by D-Ex+ per person year costs €708. At a willingness to pay €3,000 per injurious fall prevented, there was an 85.6 % chance of the exercise intervention being cost-effective in this population.
  
  
  CONCLUSIONS
  Exercise was effective in reducing fall-related injuries among community-dwelling older women at a moderate cost. Vitamin D supplementation had marginal additional benefit. The results provide a firm basis for initiating feasible and cost-effective exercise interventions in this population.
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland. radhika.patil@uta.fi.
authors.forename: R
authors.initials: R
authors.lastname: Patil
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.
authors.forename: P
authors.initials: P
authors.lastname: Kolu
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.|School of Health Sciences, University of Tampere, Tampere, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Raitanen
authors.affiliation: School of Medicine, University of Tampere, Tampere, Finland.|Purchasing Committee for the Promotion of Senior Citizens' Welfare, Tampere, Finland.|Gerontology Research Center, Universities of Jyväskylä and Tampere, Jyväskylä, Finland.|Department of Internal and Respiratory Medicine, Tampere University Hospital, Tampere, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Valvanne
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.|School of Medicine, University of Tampere, Tampere, Finland.|Department of Trauma, Musculoskeletal Surgery and Rehabilitation, Tampere University Hospital, Tampere, Finland.
authors.forename: P
authors.initials: P
authors.lastname: Kannus
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.
authors.forename: S
authors.initials: S
authors.lastname: Karinkanta
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Sievänen
authors.affiliation: The UKK Institute for Health Promotion Research, P.O. Box 30, 33501, Tampere, Finland.|Research Department, Tampere University Hospital, Tampere, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Uusi-Rasi
mesh_terms: D000058:Accidental Falls / Q000191:economics / Q000517:prevention & control*; D000368:Aged; D000369:Aged, 80 and over; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000191:economics; D003131:Combined Modality Therapy; D003362:Cost-Benefit Analysis; D019587:Dietary Supplements / Q000191:economics*; D004311:Double-Blind Method; D015444:Exercise; D005081:Exercise Therapy / Q000191:economics* / Q000379:methods; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data; D006801:Humans; D057187:Independent Living; D012680:Sensitivity and Specificity; D014807:Vitamin D / Q000008:administration & dosage* / Q000191:economics; D014947:Wounds and Injuries / Q000191:economics / Q000517:prevention & control*
chemical_list: D050071:Bone Density Conservation Agents; D014807:Vitamin D
keywords: Cost-effectiveness; Elderly; Exercise; Injurious falls; Vitamin D