Open AccessSerious Adverse Events Associated with Readmission Through One Year After Vertebral Augmentation with Either a Polyetheretherketone Implant or Balloon Kyphoplasty
Author(s) -
Douglas P. Beall
Publication year - 2017
Publication title -
pain physician
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.31
H-Index - 99
eISSN - 2150-1149
pISSN - 1533-3159
DOI - 10.36076/ppj.20.5.521
Subject(s) - medicine , adverse effect , implant , confidence interval , poisson regression , osteoporosis , surgery , randomized controlled trial , population , environmental health
Background: The KAST (Kiva Safety and Efficacy) investigation device exempt (IDE) study indicatedthat the majority of patients responded equally well to vertebral augmentation using either an implantbased approach or balloon kyphoplasty (BK). Additional investigation has suggested that a subset ofpatients may benefit further by avoiding repeated readmissions due to serious adverse events (SAEs) ifthey receive one vertebral augmentation approach over another.Objectives: The primary aim was to assess the effect of 2 different augmentation procedures onreadmission rates for SAEs.Study Design: The KAST trial is a pivotal, multicenter, randomized, controlled trial conducted toevaluate an implant-based vertebral augmentation approach (implant) against BK. Post-hoc analysis wasperformed to evaluate SAEs and readmission rates.Setting: Twenty-one sites in North America and Europe.Methods: The treatment effect of vertebral implant versus BK on SAEs requiring unplanned readmissionwas evaluated by estimating the risk of SAEs associated with readmissions in KAST while controlling forkey baseline covariates using multivariate Poisson regression modeling.Results: Forty (27.8%) patients with implants had 69 SAEs associated with readmission compared to44 (31.2%) patients with BK having 103 events. The risk for all SAEs leading to readmission was 34.4%lower with the implant than for BK (95% confidence interval = 11.1%, 51.7%; P < 0.01). Multivariateanalysis showed that the risk of SAEs associated with readmission was decreased in subjects treatedwith the implant compared to BK, and increased in patients with prior histories of vertebral compressionfractures (VCFs) or significant osteoporosis.Limitations: The power of the KIVA study was based on clinical efficacy criteria to meet FDArequirements and recommendations for equivalency or noninferiority. The primary endpoint in this posthoc analysis is SAEs associated with readmissions; as a result, the sample size is underpowered, althoughthe results remain significant.Conclusion: The augmentation approaches compared here have similar pain relief and quality of lifeeffects; the implant showed a lower risk of readmissions.