Daily Archives: January 18, 2025

RCT: Infrequent Zoledronate Infusions Reduce Vertebral Fractures in Early Postmenopausal Women Without Osteoporosis

18 Jan, 2025 | 16:48h | UTC

Background: Osteoporosis prevention typically targets older, higher-risk populations with significantly reduced bone mineral density (BMD). However, many fragility fractures occur in women who do not meet the traditional diagnostic threshold for osteoporosis (T score ≤ –2.5). This study investigated whether infrequent administration of zoledronate could prevent vertebral fractures in early postmenopausal women (50 to 60 years of age) who have BMD values between normal and osteoporotic ranges.

Objective: To determine if administering intravenous zoledronate once at baseline—and again 5 years later—could reduce the incidence of morphometric vertebral fractures and other fracture types over a 10-year period in early postmenopausal women without osteoporosis.

Methods:

• Design: A 10-year, prospective, double-blind, randomized, placebo-controlled trial.
• Population: 1054 women (mean age 56.0) within 10 years post-menopause, with lumbar spine or hip T scores <0 but >–2.5, recruited from the electoral roll in Auckland, New Zealand.
• Interventions: Participants were randomly assigned (1:1:1) to receive:
  1. Zoledronate 5 mg at baseline and again at Year 5 (zoledronate–zoledronate)
  2. Zoledronate 5 mg at baseline and placebo at Year 5 (zoledronate–placebo)
  3. Placebo infusions at baseline and Year 5 (placebo–placebo)
• Follow-up: 10 years, with repeated BMD and spine X-ray assessments at baseline, Year 5, and Year 10.
• Primary Endpoint: Incidence of new morphometric vertebral fractures, defined by semiquantitative radiographic methods.
• Secondary Endpoints: Fragility fracture, any fracture, major osteoporotic fracture, changes in BMD, and bone-turnover markers.

Results:

• Vertebral Fractures: Over 10 years, 6.3% of participants in the zoledronate–zoledronate group and 6.6% in the zoledronate–placebo group experienced a new morphometric vertebral fracture, versus 11.1% in placebo–placebo. After imputation, the relative risks versus placebo–placebo were 0.56 (95% CI, 0.34–0.92; p=0.04) and 0.59 (95% CI, 0.36–0.97; p=0.08), respectively.
• Other Fractures: The zoledronate–zoledronate group had a 30% reduced risk of any fracture (RR, 0.70; 95% CI, 0.56–0.88), and zoledronate–placebo showed a 23% reduction (RR, 0.77; 95% CI, 0.62–0.97), both compared with placebo–placebo.
• Bone Mineral Density: At Year 10, the zoledronate–zoledronate group had sustained BMD gains (~7–9 percentage points above placebo), whereas the zoledronate–placebo group retained a moderate advantage (~5–6 percentage points above placebo).
• Bone-Turnover Markers: Markers remained suppressed in the zoledronate–zoledronate group through Year 10, while in the zoledronate–placebo group, they gradually rose after Year 5 but stayed below baseline levels.
• Safety: Few adverse events were reported. Uveitis or episcleritis after the first infusion occurred in 1.1% of zoledronate recipients. No cases of osteonecrosis of the jaw or atypical femoral fractures were observed.

Conclusions: A single 5-mg dose of zoledronate, with an optional additional dose at five years, reduced the incidence of morphometric vertebral fractures and helped preserve BMD in younger postmenopausal women without osteoporosis. Both zoledronate regimens showed notable fracture-risk reductions and sustained effects on bone turnover.

Implications for Practice: These findings extend the potential role of zoledronate in fracture prevention to younger, early postmenopausal women without osteoporosis. Infrequent infusions are attractive because of their prolonged pharmacologic action and generally favorable safety profile. However, caution is warranted before broadly implementing this strategy for all postmenopausal women, as the data come from a relatively homogenous population and do not address other risk factors or comorbidities. Real-world adherence, healthcare resource allocation, and patient preferences must all be considered. Moreover, further evaluation of cost-effectiveness is essential, especially if expanding use to large populations. Longer follow-up in broader and more diverse groups may reveal less common adverse events that were not detected in this trial. Clinicians should therefore weigh individual risk–benefit profiles and await additional data before making universal recommendations.

Study Strengths and Limitations:

• Strengths: The trial’s 10-year duration, double-blind design, and high retention rate enhance its internal validity. Using radiographic assessments for vertebral fractures adds objectivity and robustness.
• Limitations: The trial predominantly involved healthy, early postmenopausal women of European descent, limiting the applicability of the findings to other ethnicities, older populations, or those with complex comorbidities. Only two zoledronate infusions at a five-year interval were evaluated, leaving the optimal dosing frequency unresolved. Further, while adverse events appeared uncommon here, the sample size and population profile may not adequately capture rare or long-latency adverse outcomes.

Future Research: Larger trials in more diverse demographic and clinical settings are necessary to determine whether infrequent zoledronate can safely and effectively reduce fracture risk across broader patient groups. Studies comparing different dosing schedules, as well as investigations into cost-effectiveness and logistics of administration, would be highly valuable. Longer-term surveillance in real-world cohorts should help clarify the incidence of uncommon adverse events. Ultimately, such additional evidence will guide whether infrequent zoledronate infusions might be integrated into routine practice for fracture prevention in postmenopausal women without osteoporosis.

Reference:

1. Bolland MJ, Nisa Z, Mellar A, et al. Fracture Prevention with Infrequent Zoledronate in Women 50 to 60 Years of Age. New England Journal of Medicine. 2025;392:239-248. DOI: http://doi.org/10.1056/NEJMoa2407031
2. Chapurlat R. Infrequent Zoledronate — Small Individual Gain, Larger Population Gain. New England Journal of Medicine. 2025;392:281-283. DOI: http://doi.org/10.1056/NEJMe2415376

 

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Screening for Osteoporosis to Prevent Fractures: Updated USPSTF Guidelines

18 Jan, 2025 | 15:19h | UTC

Introduction: This document summarizes the 2025 US Preventive Services Task Force (USPSTF) guideline on screening for osteoporosis to prevent fragility fractures. Osteoporosis, characterized by low bone mass and decreased bone quality, can lead to fractures that impair independence, increase morbidity, and raise mortality. The revised guidance builds on evidence that screening in select populations reduces fracture risk. Although the Task Force finds moderate net benefit for screening certain groups, it concludes that evidence remains insufficient to assess benefits and harms in other segments.

Key Recommendations:

1. Population and Rationale:
   • Women 65 years or older: The USPSTF concludes with moderate certainty that screening for osteoporosis in this age group leads to moderate net benefit for preventing osteoporotic fractures.
   • Postmenopausal women younger than 65 years at increased risk: Screening is recommended if a formal risk assessment or clinical risk factors indicate elevated risk, as moderate certainty suggests moderate benefit.
   • Men: The current evidence is insufficient to establish the balance of benefits and harms of screening men without known osteoporosis or prior fragility fractures.
2. Screening Methods:
   • The USPSTF identifies central dual-energy x-ray absorptiometry (DXA) of the hip or lumbar spine as the key screening test.
   • In younger postmenopausal women, a two-step approach is suggested: (1) assess risk factors (e.g., low body weight, smoking, parental history of hip fracture); (2) apply a validated tool (e.g., Osteoporosis Risk Assessment Instrument [ORAI] or Osteoporosis Self-assessment Tool [OST]) to determine who should proceed to DXA.
   • Tools such as FRAX may be used with or without BMD input to estimate 10-year fracture probability, but clinicians should be aware that tool accuracy and calibration vary by age, race/ethnicity, and underlying data sources.
3. Screening Intervals:
   • Current data do not clearly define an optimal interval for repeated screening.
   • Some evidence suggests little added value in repeating BMD tests within four to eight years if initial results are normal or only mildly low.
4. Management Following a Positive Screening Result:
   • After osteoporosis is confirmed, patients should be counseled on modifiable risk factors (e.g., smoking cessation, fall prevention) and assessed for pharmacotherapy.
   • Approved treatments (e.g., bisphosphonates, denosumab) have demonstrated benefit in reducing vertebral, hip, and other major fractures.
5. Harms of Screening and Treatment:
   • Screening anxiety and overdiagnosis are minimal concerns, though data are limited.
   • Bisphosphonate use has not been associated with significant excess serious adverse events in short- to medium-term trials, but rare events (e.g., atypical femur fractures, osteonecrosis of the jaw) remain possible with long-term use.
   • Denosumab reduces multiple fracture outcomes, though discontinuation can lead to rebound bone loss and increased risk of vertebral fractures without follow-up management.
   • The USPSTF underscores that treatment decisions should be individualized, especially in diverse populations and those with complex comorbidities.

Conclusion: These updated recommendations highlight the importance of osteoporosis screening in women 65 years or older and in younger postmenopausal women at higher fracture risk. Early detection with central DXA, informed by clinical risk tools, can reduce fracture incidence and related burdens. Further research is needed to clarify optimal screening intervals, the role of screening in men, and long-term treatment strategies. In the meantime, clinicians should collaborate with patients to personalize screening and treatment plans, considering both clinical risks and patient preferences.

Reference:

• US Preventive Services Task Force. Screening for Osteoporosis to Prevent Fractures: US Preventive Services Task Force Recommendation Statement. JAMA. Published online January 14, 2025. DOI: http://doi.org/10.1001/jama.2024.27154
• Editorials:
  • Ensrud KE, Crandall CJ. Fracture Risk Assessment as a Component of Osteoporosis Screening—Easier Said Than Done. JAMA. Published online January 14, 2025. DOI: http://doi.org/10.1001/jama.2024.27416
  • Ott SM. Research That Could Broaden the Scope of Bone Density Screening. JAMA Netw Open. 2025;8(1):e2460746. DOI: http://doi.org/10.1001/jamanetworkopen.2024.60746
• Evidence Report:
  • Kahwati LC, Kistler CE, Booth G, et al. Screening for Osteoporosis to Prevent Fractures: A Systematic Evidence Review for the US Preventive Services Task Force. JAMA. Published online January 14, 2025. DOI: http://doi.org/10.1001/jama.2024.21653

 

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