Rofecoxib does not appear to increase the risk of venous thromboembolism: A systematic review of the literature

Incidence of venous thromboembolism following initiation of non-steroidal anti-inflammatory drugs in U.S. women

OBJECTIVE

To evaluate the risk of venous thromboembolism (VTE, i.e. deep vein thrombosis or pulmonary embolism, or both) following new use of NSAIDs in a long-term cohort of U.S. women.

METHODS

We investigated initiation of coxibs and traditional NSAIDs (excluding aspirin) and incident VTE in 39 876 women enrolled in the Women's Health Study from 1993-95 and followed with yearly questionnaires until 2012. We defined initiation as the first reported use of NSAIDs for ≥4 days per month. Incident VTE was confirmed by an end point committee. We estimated hazard ratios (HRs) and risk differences (RDs, expressed as percentages) comparing NSAID initiation with non-initiation and acetaminophen initiation (active comparator) via standardization using a propensity score that incorporated age, BMI, calendar time, and relevant medical, behavioural, and socioeconomic variables updated over time.

RESULTS

The HR (95% CI) for risk of VTE in the as treated analyses comparing initiation with non-initiation, was 1.5 (1.2, 1.8) for any NSAID, 1.3 (1.1, 1.7) for traditional NSAIDs, and 2.0 (1.3, 3.1) for coxibs, with 2-year RDs 0.11, 0.08 and 0.32, respectively. When comparing the risk of VTE after initiation of any NSAID with that after acetaminophen initiation, the HRs were 0.9 (0.6, 1.5), 0.9 (0.5, 1.5) and 1.4 (0.6, 3.4), with 2-year RDs 0.03, -0.01, and 0.13, respectively.

CONCLUSION

New use of NSAIDs was associated with increased VTE risk compared with non-use, but the association was null or diminished when compared with acetaminophen initiation. Elevated VTE risks associated with NSAID use in observational studies may in part reflect different baseline risks among individuals who need analgesics and may overstate the risk patients incur compared with pharmacologic alternatives.

Prostaglandin-endoperoxide synthase-2 deletion affects the natural trafficking of Annexin A2 in monocytes and favours venous thrombosis in mice

Deep-vein thrombosis (DVT) is a common condition that often leads to pulmonary thromboembolism (VTE) and death. The role of prostaglandin-endoperoxide synthase (PTGS)2 in arterial thrombosis has been well established, whereas its impact in venous thrombosis remains unclear. Here, we showed that PTGS2 deletion predisposes to venous thrombosis as suggested by greater clot firmness and clot elasticity, by higher plasma levels of functional fibrinogen, factor VIII and PAI-1 activity, and proved by bigger thrombi detected after inferior vena cava ligation (IVCL) compared to WT mice. PTGS2^-/- thrombi have greater fibrin content, higher number of F4/80⁺, TF⁺ and ANXA2⁺ cells, and lower S100A10⁺ cells. Remarkably, monocyte depletion reduced thrombus size in mutant mice, suggesting an important role of PTGS2^-/- monocytes in this experimental setting. Interestingly, PTGS2 deletion reduced membrane ANXA2, and total S100A10, promoted assembly of ANXA2/p50NF-kB complex and its nuclear accumulation, and induced TF in peritoneal macrophages, whereas ANXA2 silencing decreased dramatically TF. Finally, Carbaprostacyclin treatment prevented venous thrombus formation induced by IVCL in mutant mice, reduced the ANXA2 binding to p50NF-kB subunit and its nuclear trafficking, and decreased TF in PTGS2^-/- macrophages. PTGS2 deletion, changing the natural distribution of ANXA2 in monocytes/macrophages, increases TF expression and activity predisposing to venous thrombosis. Interestingly, Carbaprostacyclin treatment, inhibiting nuclear ANXA2 trafficking, controls monocyte TF activity and prevents DVT occurrence. Our data are of help in elucidating the mechanisms by which PTGS2 inhibition increases DVT risk, and suggest a new role for ANXA2 in venous thrombosis.