Page 1
This month we report the risk of MI in patients taking NSAIDs, plus we show that acute respiratory infections may trigger ACS, particularly in the first week after infection. A single high-sensitivity cardiac troponin T (hs-TnT) measurement below the limit of detection may be useful for ruling out AMI in patients presenting to the ED with chest pain (although the costs of using hs-TnT in this way are high), and US researchers compare the cost- effectiveness of apixaban and warfarin in AF patients. The issue finishes with a study of the novel use of apheresis in patients with refractory angina and raised lipoprotein(a) levels. We hope you find these and the other selected studies interesting, and look forward to receiving any feedback you may have. This systematic review and meta-analysis investigated the risk of AMI in patients taking oral NSAIDs. A search of Canadian and European healthcare databases identified a cohort of 446,763 individuals (61,460 with AMI) that were suitable for inclusion in the analysis. Taking any dose of NSAIDs for 1 week, 1 month, or >1 month was associated with an increased risk of MI. With use for up to 1 week, the probability of increased MI risk (odds ratio >1.0) was 92% for celecoxib, 97% for ibuprofen, and 99% for diclofenac, naproxen, and rofecoxib. Corresponding odds ratios were 1.24 for celecoxib, 1.48 for ibuprofen, 1.50 for diclofenac, 1.53 for naproxen, and 1.58 for rofecoxib. Higher doses of NSAIDs were associated with a greater risk of MI. When used for >1 month, risks did not appear to exceed those associated with shorter durations. There has been considerable debate around the strength of the relationship between NSAID use and MI. This and many other papers shows that there is a small risk with NSAID use, and that the higher the dose, the greater the risk, especially early in the course of treatment. The postulated mechanism is that NSAIDs increase the chances of thrombosis occurring in patients with vulnerable plaques that rupture, by changing the balance between thromboxane and prostacyclins. It is suggested that these drugs be avoided in patients with underlying coronary artery disease, especially if they have had an acute event.