Antiplatelet Therapy Use and the Risk of Venous Thromboembolic Events in the Raloxifene Use for the Heart (RUTH) Trial

Abstract Background: Raloxifene use in postmenopausal women with osteoporosis increases the risk of venous thromboembolic events (VTE) 2-fold compared with placebo. Platelet activation is involved in the pathophysiology of arterial thromboses more than venous thromboses, but aspirin may reduce VTE risk associated with estrogen use. This analysis examines the effects of concomitant antiplatelet therapy on VTE risk in raloxifene-treated women. Methods: In the Raloxifene Use for the Heart (RUTH) trial, 10,101 postmenopausal women from 177 sites in 26 countries at increased risk of coronary heart disease (CHD) (primary prevention cohort) or with CHD (secondary prevention cohort) were randomized to placebo or raloxifene 60?mg/day and followed for a median 5.6 years. Reports of clinical symptoms of VTE were assessed. Concomitant use of antiplatelet agents (aspirin, clopidogrel, ticlopidine, dipyridamole) was allowed. Cox proportional hazard models, with use of warfarin, presence of fracture, and hospitalization as covariates, were used to estimate hazard ratios (HR) with 95% confidence intervals (CI). Results: Overall, raloxifene use was associated with an increased VTE risk (HR 1.44, 95% CI 1.06-1.95) vs. placebo. Most women (72%) reported using aspirin, and 14.2% reported using nonaspirin antiplatelet agents during the study period. Users of antiplatelet agents were older, more likely to have CHD, and more likely to be hyperlipidemic. They had a higher VTE risk than nonusers. No difference in VTE risk was observed in women who used raloxifene alone vs. those who used raloxifene with antiplatelet agents during the study. The increase in VTE risk with raloxifene compared with placebo was not different between women who used antiplatelet agents at baseline (HR 1.44, 95% CI 0.98, 2.10) and those who did not use antiplatelet agents (HR 1.37, 95% CI 0.83, 2.27) (interaction p?=?0.88). Similar conclusions were noted for aspirin and nonaspirin antiplatelet use. Conclusions: In RUTH, postmenopausal women treated with raloxifene had an increased risk of VTE compared with placebo. Concomitant use of aspirin or nonaspirin antiplatelet agents along with raloxifene did not change VTE risk.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/85099/1/jwh_2009_1687.pd

Baseline Glucocorticoid Dose and Bone Mineral Density Response with Teriparatide or Alendronate Therapy in Patients with Glucocorticoid-induced Osteoporosis

Objective. This post-hoc analysis studied the effect of baseline glucocorticoid dose on the 18-month bone mineral density (BMD) response to teriparatide 20 mu g/day or alendronate 10 mg/day in 387 patients with glucocorticoid-induced osteoporosis (GIO) from a randomized, double-blind trial. Methods. Lumbar spine (LS), femoral neck (FN), and total hip (TH) BMD were measured at baseline and 18 months. Mean baseline glucocorticoid dose was categorized as low ( 5 and = 15 mg/day). Results. Baseline LS, FN, and TH BMD were similar between groups, and between glucocorticoid dose categories within each group. LS BMD increases at the low, medium, and high glucocorticoid doses were 8.1%, 6.6%, and 4.6%, respectively, with teriparatide, and 3.6%, 2.8%, and 2.3% with alendronate. Analyzed as a continuous variable, higher glucocorticoid doses had a negative, but nonsignificant, effect on the percentage increase in LS BMD in both groups. Glucocorticoid dose did not significantly affect FN or TH BMD increases in either group. Across the 3 glucocorticoid dose categories, the overall LS BMD increases were different for both treatments combined (p = 0.033), but the relative differences between the treatment groups were not different (interaction, p = 0.52). Conclusion. Teriparatide and alendronate increased LS and hip BMD across a range of baseline glucocorticoid doses. LS BMD increases with teriparatide were greater in the low-dose category than in the high-dose category. Overall LS BMD increases were significantly greater with teriparatide compared with alendronate, which may reflect the respective anabolic and antiresorptive mechanisms of action. Clinical Trial Registry Number: NCT00051558. (First Release Nov 15 2009; J Rheumatol 2010;37:141-8; doi:10.3899/jrheum.090411

Baseline Glucocorticoid Dose and Bone Mineral Density Response with Teriparatide or Alendronate Therapy in Patients with Glucocorticoid-induced Osteoporosis

ABSTRACT. Objective. This post-hoc analysis studied the effect of baseline glucocorticoid dose on the 18-month bone mineral density (BMD) response to teriparatide 20 µg/day or alendronate 10 mg/day in 387 patients with glucocorticoid-induced osteoporosis (GIO) from a randomized, double-blind trial. Methods. Lumbar spine (LS), femoral neck (FN), and total hip (TH) BMD were measured at baseline and 18 months. Mean baseline glucocorticoid dose was categorized as low (≤ 5 mg/day), medium (> 5 and < 15 mg/day), or high (≥ 15 mg/day). Results. Baseline LS, FN, and TH BMD were similar between groups, and between glucocorticoid dose categories within each group. LS BMD increases at the low, medium, and high glucocorticoid doses were 8.1%, 6.6%, and 4.6%, respectively, with teriparatide, and 3.6%, 2.8%, and 2.3% with alendronate. Analyzed as a continuous variable, higher glucocorticoid doses had a negative, but nonsignificant, effect on the percentage increase in LS BMD in both groups. Glucocorticoid dose did not significantly affect FN or TH BMD increases in either group. Across the 3 glucocorticoid dose categories, the overall LS BMD increases were different for both treatments combined (p = 0.033), but the relative differences between the treatment groups were not different (interaction, p = 0.52). Glucocorticoids effectively treat inflammatory conditions but are associated with an array of side effects 1 , including secondary osteoporosis 2 . The pathophysiology of glucocorticoid-induced osteoporosis (GIO) involves multiple mechanistic pathways, including early increases in bone resorption along with decreased bone formation, and alterations in bone microarchitecture 3 . Daily or cumulative oral glucocorticoid doses are related to decreased bone mass and the occurrence of fractures 2,4 . However, patients treated with oral glucocorticoids experience fractures at a higher bone mineral density (BMD) than patients with postmenopausal osteoporosis 5 , and the fracture risk is greater than predicted by decreased bone mass alone 6 , suggesting that glucocorticoids can also negatively affect bone quality 1,2,5 . Other mechanisms of bone fragility, such as osteocyte apoptosis and reduced repair of local defects, may contribute to the increased fracture risk observed in patients treated with chronic glucocorticoids 7 . Current guidelines for management of GIO include assessment of patients for osteoporosis risk factors prior to initiating glucocorticoid therapy, concomitant use of calcium and vitamin D supplements, and for prolonged treatment of the underlying disease, minimizing the glucocorticoid dose and/or tapering the glucocorticoid dose in low disease Conclusion