High serum nitrates levels in non-survivor COVID-19 patients

Objective

Higher blood nitrate and nitrite levels have been found in coronavirus disease 2019 (COVID-19) patients than in healthy subjects. The present study explores the potential association between serum nitrate levels and mortality in COVID-19 patients.

Design

A prospective observation study was carried out.

Setting

Eight Intensive Care Units (ICUs) from 6 hospitals in the Canary Islands (Spain).

Patients

COVID-19 patients admitted to the ICU.

Interventions

Determination of serum nitrate levels at ICU admission.

Main variable of interest

Mortality at 30 days.

Results

Non-surviving (n = 11) compared to surviving patients (n = 42) showed higher APACHE-II (p < 0.001) and SOFA scores (p = 0.004), and higher serum nitrate levels (p = 0.001). Logistic regression analyses showed serum nitrate levels to be associated to 30-day mortality after controlling for SOFA (OR = 1.021; 95%CI = 1.006–1.036; p = 0.01) or APACHE-II (OR = 1.023; 95%CI = 1.006–1.041; p = 0.01). There were no differences in the area under the curve (AUC) for mortality prediction by serum nitrate levels (AUC = 83%; 95%CI = 73–92%; p < 0.001), APACHE II (AUC = 85%; 95%CI = 75–96%; p < 0.001) and SOFA (AUC = 78%; 95%CI = 63–92%; p = 0.005) based on the DeLong method. The Kaplan–Meier analysis found patients with serum nitrates levels > 68.4 μmol/l to have a higher mortality rate (hazard ratio = 138.8; 95%CI = 22.3–863.9; p < 0.001).

Conclusions

The main novel finding was the association between serum nitrate levels and mortality in COVID-19 patients controlling for the SOFA or APACHE-II scores, though larger studies are needed to confirm this observation.

High serum nitrates levels in non-survivor COVID-19 patients

OBJECTIVE

Higher blood nitrate and nitrite levels have been found in coronavirus disease 2019 (COVID-19) patients than in healthy subjects. The present study explores the potential association between serum nitrate levels and mortality in COVID-19 patients.

DESIGN

A prospective observation study was carried out.

SETTING

Eight Intensive Care Units (ICUs) from 6 hospitals in the Canary Islands (Spain).

PATIENTS

COVID-19 patients admitted to the ICU.

INTERVENTIONS

Determination of serum nitrate levels at ICU admission.

MAIN VARIABLE OF INTEREST

Mortality at 30 days.

RESULTS

Non-surviving (n=11) compared to surviving patients (n=42) showed higher APACHE-II (p<0.001) and SOFA scores (p=0.004), and higher serum nitrate levels (p=0.001). Logistic regression analyses showed serum nitrate levels to be associated to 30-day mortality after controlling for SOFA (OR=1.021; 95%CI=1.006-1.036; p=0.01) or APACHE-II (OR=1.023; 95%CI=1.006-1.041; p=0.01). There were no differences in the area under the curve (AUC) for mortality prediction by serum nitrate levels (AUC=83%; 95%CI=73-92%; p<0.001), APACHE II (AUC=85%; 95%CI=75-96%; p<0.001) and SOFA (AUC=78%; 95%CI=63-92%; p=0.005) based on the DeLong method. The Kaplan-Meier analysis found patients with serum nitrates levels>68.4μmol/l to have a higher mortality rate (hazard ratio=138.8; 95%CI=22.3-863.9; p<0.001).

CONCLUSIONS

The main novel finding was the association between serum nitrate levels and mortality in COVID-19 patients controlling for the SOFA or APACHE-II scores, though larger studies are needed to confirm this observation.

Serum caspase-3 levels during the first week of traumatic brain injury

OBJECTIVE

Confluence between the intrinsic and extrinsic apoptosis pathways is reached at the point of caspase-3 activation, which induces death cell. Higher serum caspase-3 levels have been recorded on day 1 of traumatic brain injury (TBI) in 30-day non-survivors compared to survivors. The objectives of this study therefore were to determine whether serum caspase-3 levels are persistently higher in non-survivors than in survivors, and whether these levels may be used to predict 30-day mortality.

DESIGN

A prospective observational study was carried out.

SETTING

Six Spanish Intensive Care Units.

PATIENTS

Patients with severe isolated TBI (defined as Glasgow Coma Scale <9 points and non-cranial Injury Severity Score <10 points).

INTERVENTIONS

Serum caspase-3 concentrations were measured on days 1, 4 and 8 of TBI.

MAIN VARIABLES OF INTEREST

Thirty-day mortality was considered as the study endpoint.

RESULTS

In comparison with non-survivors (n=34), 30-day survivors (n=90) showed lower serum caspase-3 levels on days 1 (p=0.001), 4 (p<0.001) and 8 (p<0.001) of TBI. Analysis of the ROC curves showed serum caspase-3 concentrations on days 1, 4 and 8 of TBI to have an AUC (95% CI) in predicting 30-day mortality of 0.70 (0.61-0.78; p=0.001), 0.83 (0.74-0.89; p<0.001) and 0.87 (0.79-0.93; p<0.001), respectively.

CONCLUSIONS

The novel findings of our study were that serum caspase-3 levels during the first week of TBI were lower in survivors and could predict 30-day mortality.

DNA and RNA oxidative damage are associated to mortality in patients with cerebral infarction

OBJECTIVE

Secondary injury due to oxidation may occur during ischemic stroke, possibly leading to oxidative damage to deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Higher blood concentrations of 8-hydroxy-2'-deoxyguanosine (8-OHdG) (through the oxidation of guanosine from DNA) have been found in ischemic stroke patients than in healthy subjects, and in patients with versus without post-ischemic stroke depression. The present study was carried out to explore the possible association between serum DNA and RNA oxidative damage and mortality in patients with cerebral infarction.

METHODS

A prospective, multicenter observational study was carried out in the Intensive Care Units of 6 Spanish hospitals. We included patients with severe malignant middle cerebral artery infarction (MMCAI) defined as ischemic changes evidenced by computed tomography in more than 50% of the middle cerebral artery territory and a Glasgow Coma Score (GCS)<9. Serum concentrations of the three oxidized guanine species (OGS) (8-hydroxyguanine from DNA or RNA, 8-hydroxyguanosine from RNA, and 8-OHdG from DNA) on the day of MMCAI diagnosis were determined. The study endpoint was 30-day mortality.

RESULTS

We found higher serum OGS levels (p<0.001) in non-surviving (n=34) than in surviving patients (n=34). Logistic regression analyses showed serum OGS levels to be associated to 30-day mortality controlling for lactic acid, GCS and platelet count (OR=1.568; 95%CI=1.131-2.174; p=0.01).

CONCLUSIONS

The novel observation in this study is the association between global serum OGS concentration and mortality in ischemic stroke patients.