Evidence Explainer · Bone health
Testosterone did not prevent fractures in TRAVERSE
Clinical fractures occurred in 3.50% assigned testosterone and 2.46% assigned placebo over median 3.19 years. An earlier BMD improvement did not establish fracture prevention—and the later clinical outcome moved in the opposite direction.
Discovery, counterevidence, claim mapping, identifiers, funding, correction state and prose were reviewed before release.
Evidence at a glance
Clinical fractures—not a bone-density surrogate
- Study type
- Randomized, double-blind clinical-fracture substudy
- Studied in
- Humans
- Participants / sample
- 5,204 TRAVERSE participants; middle-aged and older men with symptoms, repeated low testosterone and preexisting or high cardiovascular risk
- Publication status
- Peer reviewed; no linked correction, retraction or expression of concern identified as of verification
- Outcome type
- Adjudicated clinical fractures
- Evidence maturity
- Large randomized clinical-outcome evidence over median 3.19 years
- Conflicts / funding
- Parent TRAVERSE program funded by AbbVie and other testosterone manufacturers
- Our assessment
- Testosterone did not reduce fractures; the higher observed fracture incidence prevents a fracture-benefit claim
Read this first
Three takeaways
- Clinical fracture occurred in 91 of 2,601 participants (3.50%) assigned testosterone and 64 of 2,603 (2.46%) assigned placebo; hazard ratio 1.43, 95% CI 1.04–1.97.
- The result does not show fracture prevention. It also does not, by itself, identify why fractures were higher.
- A separate 211-person one-year substudy found improved volumetric BMD and estimated strength. Those surrogate measurements cannot replace the later clinical-fracture outcome.
Keep outcomes separate
A surrogate and a patient outcome can point in different directions
Bone density
The earlier substudy measured volumetric BMD and estimated strength after one year.
Clinical fractures
The later, larger substudy measured adjudicated fractures over median 3.19 years.
Mechanism
The trial did not establish a reason for the higher fracture incidence.
Longevity
Neither result demonstrates slower aging, disability prevention or longer life.
The bottom line
Testosterone treatment did not reduce clinical fractures in TRAVERSE. Fractures were observed more often in the testosterone group, so the trial cannot support a fracture-prevention claim.
What researchers did
The fracture substudy followed 5,204 TRAVERSE participants assigned daily testosterone or placebo gel. At visits, reported fractures were documented from medical records and adjudicated; the primary analysis measured time to first clinical fracture.
What they found
Over median 3.19 years, clinical fracture occurred in 3.50% assigned testosterone and 2.46% assigned placebo; hazard ratio 1.43, 95% CI 1.04–1.97. Other fracture endpoints also appeared numerically higher with testosterone.
How strong is the evidence?
This is a large randomized clinical-outcome analysis. It directly answers the fracture question more strongly than a smaller, shorter trial measuring only bone density or estimated strength.
What this does not show
The analysis does not establish why fractures were higher, identify a causal pathway, or show the same result for every formulation and population. It does not erase appropriate treatment for diagnosed conditions or provide an individual risk estimate.
Safety, surrogates and conflicts
A 211-person Testosterone Trials substudy reported a 6.8-percentage-point treatment effect for spine trabecular volumetric BMD after one year. That biomarker did not establish fracture prevention. TRAVERSE was industry funded; the earlier bone substudy was principally publicly supported with manufacturer assistance disclosed.
What happens next
Analyses of fracture type, timing, trauma context, falls and longer follow-up may help explain the unexpected pattern. Until then, the mechanism is uncertain and the clinical result should not be softened by the earlier surrogate.
Educational boundary
This article explains trial outcomes. It is not personalized medical advice and does not diagnose osteoporosis or hypogonadism, calculate fracture risk, recommend a product or tell a person to start, stop or change testosterone.
Primary sources
Sources, roles and limits
- TRAVERSE clinical-fracture substudy
- Identifier
- PMID:38231621 · DOI:10.1056/NEJMoa2308836 · NCT03518034
- Role
- Primary randomized clinical-fracture support
- Limitation
- Unexpected outcome in the selected TRAVERSE population; does not establish mechanism.
- Testosterone Trials bone-density substudy
- Identifier
- PMID:28241231 · DOI:10.1001/jamainternmed.2016.9539 · NCT00799617
- Role
- Earlier surrogate contrast
- Limitation
- 211 participants, one year, volumetric BMD and estimated strength—not fractures.
- TRAVERSE registry record
- Identifier
- NCT03518034
- Role
- Parent-trial identity, population, sponsor and results context
- Limitation
- Registry inclusion or completion is not proof of safety, benefit or scientific validity.
- Testosterone Trials registry record
- Identifier
- NCT00799617
- Role
- Bone-substudy parent identity and posted-results context
- Limitation
- The coordinated trials were too short and small for broad fracture or long-term safety conclusions.
Connected topics
Continue through the knowledge system
Continue with real coverage
Keep reading
These are learning paths, not rankings or recommendations.
A treatment trial that measured fractures directly
Zoledronic acid reduced fractures in osteoporosis—not aging itself
HORIZON reduced vertebral and hip fractures in postmenopausal osteoporosis, with outcome-specific duration and safety limits—not evidence of slower aging.
Evidence scopeHuman fracture outcomes · large randomized trial
Another bone-health study that keeps density separate from fractures
LIFTMOR improved bone density in a small supervised trial—not fracture prevention
LIFTMOR found BMD and function gains in a small, screened, closely supervised trial—not fracture prevention or proof that unsupervised heavy training is safe.
Evidence scopeHuman BMD and function · small supervised randomized trial
Another randomized prevention trial with a fracture outcome
Vitamin D is essential. VITAL still found no broad prevention benefit
In generally healthy adults, vitamin D3 did not significantly reduce invasive cancer, major cardiovascular events, or fractures; deficiency treatment is a different question.
Evidence scopeHuman clinical outcomes · large randomized prevention trial
Disclosures and history
- August 3, 2026 — source discovery and independent verification completed before prose drafting.
- August 3, 2026 — atomic population, formulation, outcome, safety, funding and longevity boundaries reviewed.
- Corrections: no linked correction, retraction or expression of concern identified for the featured primary papers as of verification; regulator and registry records must be rechecked when this story is updated.