Clopidogrel increases risk of pneumonia compared with aspirin in acute ischemic minor stroke patients

Aspirin Plus Clopidogrel Reduces Infection Risk Compared With Aspirin or Clopidogrel Alone in Acute Ischemic Stroke

PURPOSE

Activated platelets modulate immune responses. Platelet activation coincides with poststroke immunosuppression, so we hypothesized that platelet inhibition would mitigate immunosuppression and decrease the risk of infectious complications after stroke. In this study, we aimed to evaluate the contribution of platelet inhibition by antiplatelet agents to poststroke infection.

METHODS

We performed a prospective cohort study of 975 patients with acute ischemic stroke to compare the differences in the risk of infection within 7 days after admission between aspirin alone, clopidogrel alone and aspirin plus clopidogrel. Multivariable Cox proportional hazards regression model was used to assess the association between antiplatelet therapy and poststroke infection.

FINDINGS

Among 975 included patients, 578 received aspirin, 98 received clopidogrel, and 299 received both. A total of 113 patients experienced poststroke infection within 7 days after admission. The combination of aspirin and clopidogrel decreased the risk of poststroke infection compared with aspirin alone (hazard ratio [HR], 0.41; 95% confidence interval [CI], 0.22-0.77; P = 0.006), as compared with clopidogrel alone (HR, 0.46; 95% CI, 0.22-1.00; P = 0.050). We found no difference in infection risk between clopidogrel and aspirin. When assessing site-specific infections, a significant difference was observed only in the risk of pneumonia between dual antiplatelet therapy and aspirin alone.

IMPLICATIONS

Dual antiplatelet therapy with aspirin and clopidogrel is associated with decreased infection after stroke compared with aspirin or clopidogrel monotherapy. The findings support the net protective effect of aspirin and clopidogrel against poststroke infection.

Combined prognostic significance of white blood cell count and D-dimer on in-hospital outcomes of acute ischemic stroke

BACKGROUND AND AIMS

The prognostic significance of combination of white blood cell (WBC) and D-dimer on acute ischemic stroke (AIS) remains to be explored. We aimed to investigate the combined effect of WBC and D-dimer levels on in-hospital outcomes of AIS patients.

METHODS AND RESULTS

801 AIS patients were included. Patients were divided into four groups according to the cut-point identified by receiver operating characteristic (ROC) curve of D-dimer (1.105 μg/L) and WBC (7.05 × 109/L): LWLD (low WBC count and low D-dimer), LWHD (low WBC count and high D-dimer), HWLD (high WBC count and low D-dimer), and HWHD (high WBC count and high D-dimer). HWHD group had the highest cumulative incidence of in-hospital mortality (hazard ratio, 5.79; 95%CI, 1.71-19.58, P = 0.006). Patients in HWHD group were 4.14 fold more likely to have in-hospital pneumonia (odds ratio, 4.14; 95%CI, 2.09-8.21; P < 0.001), compared with those in LWLD group. The area under curve (AUC) of the combination of WBC and D-dimer levels for in-hospital mortality and pneumonia was larger than that of WBC and D-dimer alone (0.920 vs. 0.900 vs. 0.915; 0.831 vs. 0.829 vs. 0.807).

CONCLUSIONS

The combination of WBC count and D-dimer levels at admission was independently associated with in-hospital outcomes of AIS patients. The addition of WBC to D-dimer levels had a tendency to improve the predictive power for in-hospital mortality and pneumonia.

The Interplay Between Coagulation and Inflammation Pathways in COVID-19-Associated Respiratory Failure: A Narrative Review

The novel coronavirus disease (COVID-19) pandemic has caused an unprecedented worldwide socio-economic and health impact. There is increasing evidence that a combination of inflammation and hypercoagulable state are the main mechanisms of respiratory failure in these patients. This narrative review aims to summarize currently available evidence on the complex interplay of immune dysregulation, hypercoagulability, and thrombosis in the pathogenesis of respiratory failure in COVID-19 disease. In addition, we will describe the experience of anticoagulation and anti-inflammatory strategies that have been tested. Profound suppression of the adaptive and hyperactivity of innate immune systems with macrophage activation appears to be a prominent feature in this infection. Immune dysregulation together with endotheliitis and severe hypercoagulability results in thromboinflammation and microvascular thrombosis in the pulmonary vasculature leading to severe respiratory distress. Currently, some guidelines recommend the use of prophylactic low molecular weight heparin in all hospitalized patients, with intermediate dose prophylaxis in those needing intensive care, and the use of therapeutic anticoagulation in patients with proven or suspected thrombosis. Strong recommendations cannot be made until this approach is validated by trial results. To target the inflammatory cascade, low-dose dexamethasone appears to be helpful in moderate to severe cases and trials with anti-interleukin agents (e.g., tocilizumab, anakinra, siltuximab) and non-steroidal anti-inflammatory drugs are showing early promising results. Potential newer agents (e.g., Janus kinase inhibitor such as ruxolitinib, baricitinib, fedratinib) are likely to be investigated in clinical trials. Unfortunately, current trials are mostly examining these agents in isolation and there may be a significant delay before evidence-based practice can be implemented. It is plausible that a combination of anti-viral drugs together with anti-inflammatory and anti-coagulation medicines will be the most successful strategy in managing severely affected patients with COVID-19.