BACKGROUND: To investigate risks of hospitalization for upper gastrointestinal bleeding (UGIB) in H. pylori-eradicated patients newly started on warfarin or direct oral anti-coagulants (DOACs).
METHODS: We identified all patients who had previously received H. pylori eradication therapy or were found to have no H. pylori on endoscopy and were then newly started on warfarin or DOACs from a population-based electronic healthcare database. Primary analysis was the risk of UGIB between warfarin and DOACs users in H. pylori-eradicated patients. Secondary analysis included the UGIB risk between H. pylori-eradicated and H. pylori-negative patients who were newly started on warfarin or DOACs. The hazard ratio (HR) of UGIB was approximated by pooled logistic regression model incorporating the inverse propensity of treatment weightings with time-varying covariables.
RESULTS: Among H. pylori-eradicated patients, DOACs had a significantly lower risk of UGIB (HR: 0.26, 95% CI 0.09-0.71) compared with warfarin. In particular, lower UGIB risks with DOACs were observed among older (≥65 years) patients, female, those without a history of UGIB or peptic ulcer, or ischemic heart disease, and non-users of acid-suppressive agents or aspirin. Secondary analysis showed no significant difference in UGIB risk between H. pylori-eradicated and H. pylori-negative patients newly started on warfarin (HR: 0.63,95% CI 0.33-1.19) or DOACs (HR: 1.37, 95% CI 0.45-4.22).
CONCLUSIONS: In H. pylori-eradicated patients, new users of DOACs had a significantly lower risk of UGIB than new warfarin users. Furthermore, the risk of UGIB in new warfarin or DOACs users was comparable between H. pylori-eradicated and H. pylori-negative patients.

Background: Dabigatran is a univalent low-molecular-weight direct thrombin inhibitor which was developed as an alternative to vitamin K antagonists (VKAs). However, the safety of dabigatran remains controversial so far. In this study, we aimed to compare the risk of bleeding, fatal adverse events, and the all-cause mortality of dabigatran with those of the control group by a systematic review and meta-analysis of randomized controlled trials. Methods: We systematically searched PubMed, Web of Science, Cochrane Library, Medline, Embase, Wanfang database, Clinical trial, China National Knowledge Infrastructure Chinese Scientific Journal database (VIP), and Chinese Biological Medicine database (CBM), for clinical trials on conventional treatments compared with dabigatran, published between January 2014 and July 2020. The reported outcomes, including the endpoints of primary safety, were systematically investigated. Results: Seven RCTs (n = 10,743) were included in the present systematic review. Compared to the control groups, dabigatran was not associated with an increased risk of major bleeding (relative risk [RR] 0.86, 95% confidence interval [CI]: 0.61 to 1.21, p = 0.06), intracranial hemorrhage (RR 0.89, 95% CI: 0.58 to 1.36, p = 0.41), fatal adverse reactions (RR 0.87, 95% CI: 0.65 to 1.17, p = 0.66), all-cause mortality (RR 0.88, 95% CI: 0.70 to 1.11, p = 0.45, I2 = 0%), and significantly reduced risk of clinically relevant non-major bleeding (RR 0.96, 95% CI: 0.65 to 1.42, p = 0.0007). However, dabigatran is associated with an increased risk of gastrointestinal (GI) bleeding (RR 1.78, 95% CI: 1.02 to 3.13, p = 0.05). Conclusion: Dabigatran has a favorable safety profile in terms of major bleeding, intracranial hemorrhage, and life-threatening events, among other safety outcomes. The present study suggested that dabigatran may be a suitable alternative to VKAs as an oral anticoagulant. However, more data are necessary to clarify the incidence of other adverse events and serious adverse reactions.

In order to develop an affinity HPLC method for screening direct thrombin inhibitors from Traditional Chinese Medicine (TCM), thrombin was immobilized on the glutaraldehyde-modified amino silica gel and was used as thrombin stationary phase. A thrombin affinity column (TAC) was made by packing the thrombin stationary phase into a bare column (2.0 * 1.0 mm, i.d.). The direct thrombin inhibitors could be screened through this TAC column. For the purpose of improvement of the discovery efficiency, a TAC-HPLC-MS/MS system was used to screen thrombin inhibitors from Radix Salviae Miltiorrhiae (RSM), a famous traditional Chinese medicine. After optimization of all the conditions, cryptotanshinone (Cry), dihydrotanshinone I (Dih-I) and tanshinone IIA (Tan-IIA) were screened out and identified as potential active components. The anticoagulant effects of these three compounds were tested by anticoagulant experiments in vitro. Furthermore, the interaction of three compounds with thrombin was studied by molecular docking. The result shows they have the potential to be used as preventive drugs. In short, this method can be used to screen anticoagulant drugs from traditional Chinese medicine, which provides convenience for screening anticoagulant drugs.

BACKGROUND: Argatroban, as a direct thrombin inhibitor, prolongs the clotting time. However, detection of clotting time is the base of routine fibrinogen assays, including Clauss method and derived method. The influences of argatroban on fibrinogen assays are still unclear.
METHODS: Normal pooled plasma (NPP) from 20 healthy subjects was spiked with increasing argatroban concentrations (0-3.2 μg/mL). Then the NPP samples were analyzed by five fibrinogen assays: HemosIL Fibrinogen-C XL reagent (Clauss method) on ACL-TOP; STA-Fibrinogen reagent (Clauss method) on STA-R Evolution; Siemens Thrombin reagent (Clauss method) on CS-5100; SynthASil RecombiPlasTin 2G reagent (PT-derived method) on ACL-TOP; and N Antiserum to Human Fibrinogen reagent (NAHF, Immunoassay) on BN2 nephelometer analyzer.
RESULTS: Argatroban had no influences on NAHF (P=.13). Compared with the NAHF, significant reduction was observed on Fibrinogen-C XL (P<.01), while no influences were shown on the others (STA-Fibrinogen: P=.41, Siemens Thrombin: P=.20, RecombiPlasTin 2G: P=.21) when activated partial thromboplastin time (APTT) ratio was no more than 3.0. As APTT ratio was increasing to 4.5, results from Clauss and PT-derived methods were significantly lowered (STA-Fibrinogen: P=.02, Siemens Thrombin: P<.01, Fibrinogen-C XL: P<.01, RecombiPlasTin 2G: P<.01).
CONCLUSIONS: The influences of argatroban on fibrinogen assays differ greatly, clinicians should be aware of the influences of argatroban on the fibrinogen assays used on site to avoid misdiagnoses.