Ultrasound bone mass in patients undergoing chronic therapy with oral anticoagulants.

The purpose of this study was to assess the effects of chronic oral anticoagulant (OAC) treatment on bone mass using quantitative ultrasound (QUS) techniques. A total of 120 patients (47 women and 73 men) undergoing treatment with OAC and 57 healthy subjects (27 women and 30 men) participated in this study. Bone status was assessed using QUS devices that measure the amplitude-dependent speed of sound (Ad-SoS) in phalanges and the broadband ultrasound attenuation (BUA) in the calcaneus. Men undergoing OAC treatment had lower Ad-SoS, Z-score, T-score, and BUA values (all p < 0.005) and higher levels of undercarboxylated osteocalcin (u-OC) and tartrate-resistant acid phosphatase (TRAP) (both p < 0.0001) than controls. Women receiving OAC treatment had lower BUA values (p < 0.005) and total osteocalcin (OC) levels (p < 0.0001) and higher levels of u-OC and TRAP (both p < 0.0001) than controls. There was a statistically significant negative correlation between u-OC levels and Ad-SoS values in both men (r = -0.432, p = 0.0328) and women (r = -0.332, p = 0.0269) undergoing OAC treatment. In conclusion, patients undergoing OAC treatment had a loss of trabecular and cortical bone mass, possibly due to a decrease in the γ-carboxylation of osteocalcin resulting from the vitamin K antagonism of these drugs.