Respiratory tract infection and risk of bleeding in oral anticoagulant users: self-controlled case series

Risk of bleeding amongst warfarin and direct oral anticoagulant users prescribed immediate antibiotics for respiratory tract infection: Cohort study

PURPOSE

Incidence of bleeding amongst warfarin and direct oral anticoagulant (DOAC) users is greater following a respiratory tract infection (RTI). It is unclear whether immediate antibiotics modify this association. We estimated the risk of bleeding amongst warfarin and DOAC users with RTI by antibiotic treatment.

METHODS

This retrospective cohort study used data from the Clinical Practice Research Datalink (CPRD) GOLD for adults in England prescribed warfarin or a DOAC, who sought primary care for an RTI between 1st January 2011 and 31st December 2019. Outcomes were major bleeding (hospital admission for intracranial or gastrointestinal bleeding), and non-major bleeding (hospital admission or General Practice consult for epistaxis, haemoptysis, or haematuria). Cox models derived hazard ratios (HRs) and 95% confidence intervals (CIs) for each outcome, adjusting for confounders using inverse probability of treatment weighting.

RESULTS

Of 14 817 warfarin and DOAC users consulting for an RTI, 8768 (59%) were prescribed immediate antibiotics and 6049 (41%) were not. Approximately 49% were female, and median age was 76 years. Antibiotics were associated with reduced risk of major bleeding (adjusted HR 0.38, 95% CI 0.25 to 0.58). This was consistent across several sensitivity analyses. Antibiotics were also associated with a reduced risk of non-major bleeding (adjusted HR 0.78, 95% CI 0.61 to 0.99).

CONCLUSIONS

Immediate antibiotics were associated with reduced risk of bleeding amongst warfarin and DOAC users with an RTI. Further work is needed to understand mechanisms and confirm whether a lower threshold for antibiotic use for RTI in this population may be beneficial.

Rivaroxaban Plasma Concentration and Clinical Outcomes on Older Patients with Non-valvular Atrial Fibrillation and Pulmonary Infection

INTRODUCTION

Infection may induce thrombotic and hemorrhagic events; however, it is currently unclear whether the inflammatory response affects the coagulation function and the clinical efficacy and safety of rivaroxaban in older patients with non-valvular atrial fibrillation (NVAF).

OBJECTIVE

This project aimed to assess the effectiveness and safety of the non-vitamin K antagonist oral anticoagulant rivaroxaban in older patients with NVAF complicated by infection, and to provide a basis for possible drug dose adjustment.

METHODS

A total of 152 NVAF patients aged ≥ 65 years admitted to the Fifth People's Hospital of Shanghai from June 2020 to May 2022 were included in this prospective, observational study. The changes in steady-state plasma concentration of rivaroxaban and FXa inhibition rate were compared between patients with and without infection, and the impact on the occurrence of infection, thrombotic events, and bleeding events was compared through 1-year follow-up.

RESULTS

Our results showed that patients in the infection group had abnormal inflammation markers, as well as an increased occurrence of bleeding and thrombotic events during hospitalization and follow-up. The high incidence of bleeding events in patients was closely related to the occurrence of infection, lymphocyte reduction, and increased neutrophil-lymphocyte ratio. The increase in thrombotic events was related to a decrease in rivaroxaban plasma concentration. Bleeding events in patients taking anticoagulant drugs are not necessarily due to drug accumulation.

CONCLUSIONS

Timely control of infection, assessment of bleeding and thrombotic risks, and selection of appropriate anticoagulation treatment strategies should be made in older NVAF patients who develop pulmonary infection.

CLINICAL TRIALS REGISTRATION

Chinese Clinical Trial Registry Number ChiCTR2000033144.

Limaprost and the Risk of Bleeding: A Self-Controlled Case Series Study

OBJECTIVE

To investigate the association between the use of limaprost and the risk of bleeding.

METHODS

A self-controlled case series analysis was conducted using the National Health Insurance Service-National Sample Cohort database in South Korea. We identified patients aged 18 years or older who had at least one prescription of limaprost and were diagnosed with at least one case of bleeding between 2003 and 2019. The incidence rate ratio (IRR) of bleeding was calculated by dividing the incidence rate in the exposed period to limaprost by that in the unexposed period and adjusted for age using conditional Poisson regression model.

RESULTS

Among 72,860 patients with limaprost prescriptions and bleeding diagnoses, there were 184,732 events of bleeding. After adjusting for age, the IRR was 1.47 (95% confidence interval [CI], 1.43-1.50), wherein the IRR was the highest during the 0-7 days after limaprost initiation (IRR, 2.11; 95% CI, 2.03-2.18). Risk of bleeding was higher when limaprost was concomitantly used with antithrombotics or other drugs for spinal stenosis treatment, and when higher daily doses of limaprost were administered.

CONCLUSION

Our findings suggest that the risk of bleeding increased by 1.5-fold in periods of limaprost exposure compared to unexposed periods, with particularly higher risks observed during the first week after limaprost initiation, with concomitant drugs related to bleeding, and with a higher daily dose. A careful risk-benefit assessment is warranted when initiating limaprost, especially when administered with other medications or in higher daily doses.

Severe Infection and Risk of Cardiovascular Disease: A Multicohort Study

BACKGROUND

The excess risk of cardiovascular disease associated with a wide array of infectious diseases is unknown. We quantified the short- and long-term risk of major cardiovascular events in people with severe infection and estimated the population-attributable fraction.

METHODS

We analyzed data from 331 683 UK Biobank participants without cardiovascular disease at baseline (2006-2010) and replicated our main findings in an independent population from 3 prospective cohort studies comprising 271 329 community-dwelling participants from Finland (baseline 1986-2005). Cardiovascular risk factors were measured at baseline. We diagnosed infectious diseases (the exposure) and incident major cardiovascular events after infections, defined as myocardial infarction, cardiac death, or fatal or nonfatal stroke (the outcome) from linkage of participants to hospital and death registers. We computed adjusted hazard ratios (HRs) and 95% CIs for infectious diseases as short- and long-term risk factors for incident major cardiovascular events. We also calculated population-attributable fractions for long-term risk.

RESULTS

In the UK Biobank (mean follow-up, 11.6 years), 54 434 participants were hospitalized for an infection, and 11 649 had an incident major cardiovascular event at follow-up. Relative to participants with no record of infectious disease, those who were hospitalized experienced increased risk of major cardiovascular events, largely irrespective of the type of infection. This association was strongest during the first month after infection (HR, 7.87 [95% CI, 6.36-9.73]), but remained elevated during the entire follow-up (HR, 1.47 [95% CI, 1.40-1.54]). The findings were similar in the replication cohort (HR, 7.64 [95% CI, 5.82-10.03] during the first month; HR, 1.41 [95% CI, 1.34-1.48] during mean follow-up of 19.2 years). After controlling for traditional cardiovascular risk factors, the population-attributable fraction for severe infections and major cardiovascular events was 4.4% in the UK Biobank and 6.1% in the replication cohort.

CONCLUSIONS

Infections severe enough to require hospital treatment were associated with increased risks for major cardiovascular disease events immediately after hospitalization. A small excess risk was also observed in the long-term, but residual confounding cannot be excluded.