Int J Mol Sci. 2019 Oct 24;20(21). pii: E5275. doi: 10.3390/ijms20215275.
Anticoagulant agents are widely used in the treatment of thromboembolic events and in stroke prevention. Data about their effects on bone tissue are in some cases limited or inconsistent (oral anti-vitamin K agents), and in others are sufficiently strong (heparins) to suggest caution in their use in subjects at risk of osteoporosis. This review analyses the effects of this group of drugs on bone metabolism, on bone mineral density, and on fragility fractures. A literature search strategy was developed by an experienced team of specialists by consulting the MEDLINE platform, including published papers and reviews updated to March 2019. Literature supports a detrimental effect of heparin on bone, with an increase in fracture rate. Low molecular weight heparins (LMWHs) seem to be safer than heparin. Although anti-vitamin K agents (VKAs) have a significant impact on bone metabolism, and in particular, on osteocalcin, data on bone mineral density (BMD) and fractures are contrasting. To date, the new direct oral anticoagulants (DOACs) are found to safe for bone health.
Conclusions Data of literature evidence a heterogeneous effect of anticoagulant on bone. Table 2 summarises the effects on bone metabolism, BMD and fractures of the different available anticoagulants. Data supporting a detrimental effect of heparin are sufficiently clear. LMWHs seem to be safer than heparin. Although VKAs have a significant impact on bone metabolism and, in particular, on osteocalcin, data on BMD and fractures are contrasting. To date, the new DOACs are safe for bone health (Figure 1). This evidence must be taken into consideration by medical personnel. In particular, the prolonged use of heparin and VKAs must induce an alert behaviour and put in place some prophylaxis measures, such as calcium and vitamin D supplementation. In the case of a history of fractures, or in the presence of other comorbidities or low BMD values, it is necessary to evaluate a therapy with anti-osteoporosis drugs.