Question

Please summarize the abstract of the article below. Article name is Diference of coagulation features between severe pneumonia induced by SARS-CoV2 and non-SARS-CoV2. What i dont understand is in bold.

Severe coronavirus disease 2019 (COVID-19) is commonly complicated with coagulopathy, the diference of coagulation features between severe pneumonia induced by SARS-CoV2 and non-SARS-CoV2 has not been analyzed. Coagulation results and clinical features of consecutive patients with severe pneumonia induced by SARS-CoV2 (COVID group) and non-SARS-CoV2 (non-COVID group) in Tongji hospital were retrospectively analyzed and compared. Whether patients with elevated D-dimer could beneft from anticoagulant treatment was evaluated. There were 449 COVID patients and 104 non-COVID patients enrolled into the study. The 28-day mortality in COVID group was approximately twofold of mortality in non-COVID group (29.8% vs. 15.4%, P=0.003), COVID group were older (65.1±12.0 vs. 58.4±18.0, years, P<0.001) and with higher platelet count (215±100 vs. 188±98, ×109/L, P=0.015), comparing to non-COVID group. The 28-day mortality of heparin users were lower than nonusers In COVID group with D-dimer>3.0 μg/mL (32.8% vs. 52.4%, P=0.017).Patients with severe pneumonia induced by SARS-CoV2 had higher platelet count than those induced by non-SARS-CoV2, and only the former with markedly elevated D-dimer may beneft from anticoagulant treatment.

Answer 1

The study named "Diference of coagulation features between severe pneumonia induced by SARS-CoV2 and non-SARS-CoV2" aimed to compare the coagulation parameters between severe COVID-19 patients and severe pneumonia patients induced by other pathogens through retrospective analysis. This study may be helpful for choosing appropriate treatment on coagulopathy of COVID-19. Severe coronavirus disease 2019 (COVID-19) is complicated with coagulopathy and markedly elevated D-dimer ( High D-dimer indicate the presence of an abnormally high level of fibrin degradation products. It indicates that there may be significant blood clot (thrombus) formation and breakdown in the body) which was associated with poor prognosis of severe COVID-19. The effect of SARS-CoV2 infection on pulmonary coagulation and fibrinolysis is considered to be regulated by various proinflammatory cytokines, which is similar to pneumonia induced by other pathogens. Thats why the difference among coagulation features should be studied and compared to provide appropriate treatment.

The study was conducted among 449 COVID patients and 104 non-COVID patients. Comparison was done based on clinical characteristics, coagulation results and 28-day mortality between COVID and non-COVID groups. The chronic underlying diseases within COVID and non-COVID groups included hypertension, diabetes, heart diseases and lung diseases. The study found out that the 28-day mortality in COVID group was approximately two times that of the mortality in non-COVID group (29.8% vs. 15.4%, P = 0.003), and COVID patient group were older compared to the other (65.1 ± 12.0 vs. 58.4 ± 18.0, years, P < 0.001) and they had higher platelet count (215 ± 100 vs 188 ± 98, ×10⁹/L, P = 0.015), compared to non-COVID group. The higher platelet count in COVID patients were perhaps due to the increased thrombopoietin following pulmonary inflammation, this might mean that there were more severe inflammation reaction and hypercoagulability in COVID group comapred to the other.

Heparin treatment was received by 99 patients (22.0%) of COVID group for at least 7 days, in which 94 received LMWH (40–60 mg enoxaparin/day) and 5 received UFH (10,000–15,000 U/day). Twenty two (21.2%) patients of non-COVID group received heparin treatment, in which 20 received LMWH (40–60 mg enoxaparin/day) and 2 received UFH (10,000–15,000 U/day). No anticoagulants other than heparin had been used for 7 days or longer in the study group. There was no difference on the 28-day mortality found between heparin users and nonusers in COVID group (30.3% vs. 29.7%, P = 0.910) and also in non-COVID group (13.6% vs. 15.9%, P = 0.798). The association between heparin treatment and outcome in stratified patients according to D-dimer result were evaluated and found out that when D-dimer is exceeding 3.0 μg/mL (sixfold of upper limit of normal, 6 ULN) there were significantly lower mortality in heparin users than nonusers in COVID group (32.8% vs. 52.4%, P = 0.017). But, no difference on mortality between heparin users than nonusers has been found in non-COVID group when being stratified by D-dimer.