Effects of anti-tumor necrosis factor α agents on bone

Vivian K Kawai1, C Michael Stein, Daniel S Perrien

  • 1Vanderbilt University School of Medicine, Nashville Tennessee, USA. vivian.k.kawai@vanderbilt.edu

Abstract

Insights

Tumor necrosis factor (TNF) inhibitors may help control inflammatory diseases. However, current evidence does not show they prevent bone loss or fractures better than traditional therapies.

Area of Science:

  • Rheumatology
  • Immunology
  • Bone Metabolism

Background:

  • Tumor necrosis factor (TNF) inhibitors are established treatments for inflammatory diseases.
  • While effective for disease control, their impact on bone health, specifically osteoporosis and fractures, requires further elucidation.

Purpose of the Study:

  • To review the current evidence on the role of TNF inhibitors in preventing bone loss and fractures.
  • To assess whether TNF inhibitors offer advantages over conventional therapies for bone health outcomes.

Main Methods:

  • Review of existing studies examining TNF inhibitors' effects on bone turnover markers, bone mineral density (BMD), and fracture incidence.
  • Analysis of study methodologies, including sample size and placebo control.

Main Results:

  • Numerous studies assess TNF inhibitors' impact on bone turnover markers, but few evaluate BMD or fractures.
  • Existing studies often have small sample sizes and limited placebo-controlled designs.
  • Evidence suggests anti-TNF therapy's bone-protective effects are linked to disease activity control.

Conclusions:

  • The bone-antiresorptive effects of TNF inhibitors are primarily attributed to their anti-inflammatory actions.
  • Current research does not support TNF inhibitors as superior to nonbiologic therapies for preventing bone loss and fractures.

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