Journal Facts

Journal
BoneKEy Knowledge Environment
ISSN
1940-8692
Volume
12
Year
2015

Article Facts

Title
Fracture risk in women 4-5 years after discontinuing alendronate
DOI
10.1038/bonekey.2015.24
Author
Online Date
03/04/2015

Article Links

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Fracture risk in women 4-5 years after discontinuing alendronate


DOI:10.1038/bonekey.2015.24

This report from the Fracture Intervention Trial Long-term Extension (FLEX) study reports the findings from over 4–5 years of follow up in women previously treated with alendronate and then switched to placebo.

Measurements on all women taken at baseline (the start of the placebo phase) and at the one-year and three-year points included dual-energy X-ray absorptiometry (DXA) scans of the spine and hip and measurement of two bone turnover markers: urinary type 1 collagen cross-linked N-telopeptide (NTX) and serum bone-specific alkaline phosphatase (BAP).

In the five years of follow up, 22% of the women sustained at least one symptomatic fracture. Most fractures (82/94) occurred within the first year. Neither the DXA scan results nor the levels of NTX or BAP at one-year correlated with fracture risk. The only factors found to be significantly associated with a higher risk of a fracture were older age and lower hip DXA at baseline.

Editor’s comment: When to stop and when to eventually restart osteoporosis medication after ‘drug holidays’ are unresolved issues. Data from the FLEX study indicate that an increase in BTMs one and three years after discontinuing ALN does not predict clinical fracture risk. However this was based on urinary NTX and serum BAP, which may not be the most sensitive markers, and the confidence intervals were wide. More studies are needed to guide clinicians on this important issue.

Creative Commons License This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.