In a nationwide study of women of reproductive age in Denmark, NSAID use was positively associated with venous thromboembolism, researchers report, and the risk was further increased by concomitant use of high- and medium-risk hormonal contraceptives. “Women needing both hormonal contraception and regular use of NSAIDs should be advised accordingly,” the authors conclude.
The cohort study included all 15–49-year-old women living in Denmark between 1996 and 2017 who had no medical history of any venous or arterial thrombotic event, cancer, or other conditions. Based on a primary outcome of a first-time discharge diagnosis of lower-limb deep-vein thrombosis or pulmonary embolism, the study showed the following: “Among 2.0 million women followed for 21.0 million person years, 8,710 venous thromboembolic events occurred. Compared with non-use of NSAIDs, use of NSAIDs was associated with an adjusted incidence rate ratio of venous thromboembolism of 7.2 (95% confidence interval 6.0 to 8.5) in women not using hormonal contraception, 11.0 (9.6 to 12.6) in women using high risk hormonal contraception, 7.9 (5.9 to 10.6) in those using medium risk hormonal contraception, and 4.5 (2.6 to 8.1) in users of low/no risk hormonal contraception. The corresponding numbers of extra venous thromboembolic events per 100,000 women over the first week of NSAID treatment compared with non-use of NSAIDs were 4 (3 to 5) in women not using hormonal contraception, 23 (19 to 27) in women using high risk hormonal contraception, 11 (7 to 15) in those using medium risk hormonal contraception, and 3 (0 to 5) in users of low/no risk hormonal contraception.”