Obesity, Inflammation, and Clinical Outcomes in COVID-19: A Multicenter Prospective Cohort Study.

CONTEXT: Obesity is a risk factor for coronavirus disease 2019 (COVID-19)-related outcomes; however, the mechanism remains unclear. OBJECTIVE: The objective of this analysis was to determine whether inflammation mediates the association between obesity and COVID-19 outcomes. DESIGN: The International Study of Inflammation in Covid-19 (ISIC): A Prospective Multi-Center Observational Study Examining the Role of Biomarkers of Inflammation in Predicting Covid-19 Related Outcomes in Hospitalized Patients. SETTING: Ten hospitals in the United States and Europe. PARTICIPANTS: Adults hospitalized specifically for COVID-19 between February 1, 2020, through October 19, 2022. MAIN OUTCOME MEASURES: Inflammatory biomarkers, including soluble urokinase plasminogen activator receptor (suPAR), were measured at admission. Associations were examined between body-mass index (BMI, kg/m2) and a composite of death, need for mechanical ventilation, and renal replacement therapy, stratified by pre- and post-Omicron variants. The contribution of inflammation to the relationship between obesity and outcomes was assessed. RESULTS: Among 4644 participants (mean age 59.3, 45.6% male, 21.8% BMI≥35), those with BMI>40 (n=485) had 55% higher odds of the composite outcome (95% CI[1.21 to 1.98]) compared to non-obese individuals (BMI<30, n=2358) in multivariable analysis. In multiple mediation analysis, only suPAR remained a significant mediator between BMI and composite outcome. Associations were amplified for participants younger than 65 years and with pre-Omicron variants. CONCLUSION: Obesity is associated with worse outcomes in COVID-19, notably in younger participants and in the pre-Omicron era. Inflammation, as measured by suPAR, is a significant mediator of the association between obesity and COVID-19 outcomes.

Development and validation of prognostic machine learning models for short- and long-term mortality among acutely admitted patients based on blood tests.

Several scores predicting mortality at the emergency department have been developed. However, all with shortcomings either simple and applicable in a clinical setting, with poor performance, or advanced, with high performance, but clinically difficult to implement. This study aimed to explore if machine learning algorithms could predict all-cause short- and long-term mortality based on the routine blood test collected at admission. METHODS: We analyzed data from a retrospective cohort study, including patients > 18 years admitted to the Emergency Department (ED) of Copenhagen University Hospital Hvidovre, Denmark between November 2013 and March 2017. The primary outcomes were 3-, 10-, 30-, and 365-day mortality after admission. PyCaret, an automated machine learning library, was used to evaluate the predictive performance of fifteen machine learning algorithms using the area under the receiver operating characteristic curve (AUC). RESULTS: Data from 48,841 admissions were analyzed, of these 34,190 (70%) were randomly divided into training data, and 14,651 (30%) were in test data. Eight machine learning algorithms achieved very good to excellent results of AUC on test data in a of range 0.85-0.93. In prediction of short-term mortality, lactate dehydrogenase (LDH), leukocyte counts and differentials, Blood urea nitrogen (BUN) and mean corpuscular hemoglobin concentration (MCHC) were the best predictors, whereas prediction of long-term mortality was favored by age, LDH, soluble urokinase plasminogen activator receptor (suPAR), albumin, and blood urea nitrogen (BUN). CONCLUSION: The findings suggest that measures of biomarkers taken from one blood sample during admission to the ED can identify patients at high risk of short-and long-term mortality following emergency admissions.

Capacidad del biomarcador suPAR para estratificar el pronóstico en pacientes atendidos en servicios de urgencias hospitalarios / Value of the soluble urokinase-type plasminogen activator receptor as a predictor of prognosis in patients attended in hospital emergency departments

Objetivos. Determinar la capacidad del receptor soluble del activador del plasminógeno tipo uroquinasa (suPAR) para la estratificación pronóstica en pacientes atendidos en servicios de urgencias hospitalarios (SUH). Los objetivos secundarios son: 1)medir la capacidad de los puntos de decisión habituales, 2)identificar una población de bajo riesgo de mortalidad que puede darse de alta de forma segura desde el SUH, y 3)medir la correlación entre suPAR y otros biomarcadores. Métodos. Estudio observacional de cohortes prospectivo de pacientes atendidos en SUH. Se registraron variables sociodemográficas, de comorbilidad, datos del episodio agudo, biomarcadores de uso común en urgencias y suPAR. Las variables de resultado fueron la necesidad de ingreso en el episodio índice, reconsulta al SUH y mortalidad a los 90 días. Resultados. Se incluyeron 990 pacientes, la edad fue de 68 (53-81) años, 50,8% eran hombres, la mediana de suPAR fue de 3,8 (2,8-6,0) ng/ml, 112 pacientes (11,31%) requirieron ingreso. En el seguimiento a 90 días hubo 276 reconsultas (27,9%) y 47 pacientes (4,74%) fallecieron. Los pacientes con suPAR<4 ng/ml (52,5%) tenían menor mortalidad (1%), menor reconsulta (24,4%) y menor necesidad de ingreso hospitalario (20,6%), que pacientes con suPAR>6 ng/ml (mortalidad 13,5%, reconsulta 39,6% e ingreso 56,3%). Un suPAR>6 ng/ml mostró una hazard ratio (IC 95%) ajustada de 4,61 (1,68-12,67) para predecir mortalidad a 90 días y de 1,59 (1,13-2,10) para la reconsulta, y una odds ratio de 1,62 (0,99-2,62) para la necesidad de ingreso hospitalario. Conclusiones. Un valor de suPAR < 4 ng/ml identifica pacientes con riesgo bajo de mortalidad a 90 días, de reconsulta y de necesidad de ingreso, mientras que los pacientes con suPAR>6 ng/ml tienen mayor mortalidad, reconsulta y necesidad de ingreso. (AU)

Objectives. To determine the value of the soluble urokinase-type plasminogen activator receptor (suPAR) for predicting outcomes in emergency department (ED) patients. Secondary objectives were 1)to measure the predictive value of the usual decision points, 2)to identify patients at low risk for mortality who could be safely discharged from the ED, and 3)to measure the correlation between suPAR and other biomarkers. Methods. Prospective observational cohort study of patients attended in the EDs of participating hospitals. We recorded sociodemographic variables, comorbidity, variables related to the acute episode, prognostic markers commonly used in EDs, and suPAR concentration. Outcome variables were the need for hospital admission during the index episode, ED revisits within 90 days, and 90-day mortality. Results. A total of 990 patients with a median (interquartile range) age of 68 (53-81 years) were studied; 50.8% were men. The median suPAR concentration was 3.8 (2.8-6.0) ng/mL, and 112 patients (11.31%) required admission. At 90 days there were 276 revisits (27.9% of the cohort), and 47 patients (4.74%) had died. Mortality was lower (1%) in patients with suPAR concentrations less than 4 ng/mL (52.5%), and fewer of these patients revisited (24.4%) or required hospitalization (20.6%) than patients with suPAR concentrations higher than 6 ng/mL (mortality, 13.5%; revisits, 39.6%; admissions, 56.3%). A suPAR concentration over 6 ng/mL was associated with 90-day mortality and revisits (adjusted hazard ratios and 95% CIs of 4.61 [1.68-12.67] and 1.59 [1.13-2.10]), respectively. The high suPAR concentration was also associated with hospital admission (odds ratio, 1.62 [0.99-2.62]). Conclusions. A suPAR concentration of less than 4 ng/mL identifies patients at low risk of 90-day mortality and revisits or need for hospitalization, whereas a suPAR concentration higher than 6 ng/mL is associated with higher risk for these outcomes. (AU)

Capacidad del biomarcador suPAR para estratificar el pronóstico en pacientes atendidos en servicios de urgencias hospitalarios / Value of the soluble urokinase-type plasminogen activator receptor as a predictor of prognosis in patients attended in hospital emergency departments

Objetivos. Determinar la capacidad del receptor soluble del activador del plasminógeno tipo uroquinasa (suPAR) para la estratificación pronóstica en pacientes atendidos en servicios de urgencias hospitalarios (SUH). Los objetivos secundarios son: 1)medir la capacidad de los puntos de decisión habituales, 2)identificar una población de bajo riesgo de mortalidad que puede darse de alta de forma segura desde el SUH, y 3)medir la correlación entre suPAR y otros biomarcadores. Métodos. Estudio observacional de cohortes prospectivo de pacientes atendidos en SUH. Se registraron variables sociodemográficas, de comorbilidad, datos del episodio agudo, biomarcadores de uso común en urgencias y suPAR. Las variables de resultado fueron la necesidad de ingreso en el episodio índice, reconsulta al SUH y mortalidad a los 90 días. Resultados. Se incluyeron 990 pacientes, la edad fue de 68 (53-81) años, 50,8% eran hombres, la mediana de suPAR fue de 3,8 (2,8-6,0) ng/ml, 112 pacientes (11,31%) requirieron ingreso. En el seguimiento a 90 días hubo 276 reconsultas (27,9%) y 47 pacientes (4,74%) fallecieron. Los pacientes con suPAR<4 ng/ml (52,5%) tenían menor mortalidad (1%), menor reconsulta (24,4%) y menor necesidad de ingreso hospitalario (20,6%), que pacientes con suPAR>6 ng/ml (mortalidad 13,5%, reconsulta 39,6% e ingreso 56,3%). Un suPAR>6 ng/ml mostró una hazard ratio (IC 95%) ajustada de 4,61 (1,68-12,67) para predecir mortalidad a 90 días y de 1,59 (1,13-2,10) para la reconsulta, y una odds ratio de 1,62 (0,99-2,62) para la necesidad de ingreso hospitalario. Conclusiones. Un valor de suPAR < 4 ng/ml identifica pacientes con riesgo bajo de mortalidad a 90 días, de reconsulta y de necesidad de ingreso, mientras que los pacientes con suPAR>6 ng/ml tienen mayor mortalidad, reconsulta y necesidad de ingreso. (AU)

Objectives. To determine the value of the soluble urokinase-type plasminogen activator receptor (suPAR) for predicting outcomes in emergency department (ED) patients. Secondary objectives were 1)to measure the predictive value of the usual decision points, 2)to identify patients at low risk for mortality who could be safely discharged from the ED, and 3)to measure the correlation between suPAR and other biomarkers. Methods. Prospective observational cohort study of patients attended in the EDs of participating hospitals. We recorded sociodemographic variables, comorbidity, variables related to the acute episode, prognostic markers commonly used in EDs, and suPAR concentration. Outcome variables were the need for hospital admission during the index episode, ED revisits within 90 days, and 90-day mortality. Results. A total of 990 patients with a median (interquartile range) age of 68 (53-81 years) were studied; 50.8% were men. The median suPAR concentration was 3.8 (2.8-6.0) ng/mL, and 112 patients (11.31%) required admission. At 90 days there were 276 revisits (27.9% of the cohort), and 47 patients (4.74%) had died. Mortality was lower (1%) in patients with suPAR concentrations less than 4 ng/mL (52.5%), and fewer of these patients revisited (24.4%) or required hospitalization (20.6%) than patients with suPAR concentrations higher than 6 ng/mL (mortality, 13.5%; revisits, 39.6%; admissions, 56.3%). A suPAR concentration over 6 ng/mL was associated with 90-day mortality and revisits (adjusted hazard ratios and 95% CIs of 4.61 [1.68-12.67] and 1.59 [1.13-2.10]), respectively. The high suPAR concentration was also associated with hospital admission (odds ratio, 1.62 [0.99-2.62]). Conclusions. A suPAR concentration of less than 4 ng/mL identifies patients at low risk of 90-day mortality and revisits or need for hospitalization, whereas a suPAR concentration higher than 6 ng/mL is associated with higher risk for these outcomes. (AU)

Value of the soluble urokinase-type plasminogen activator receptor as a predictor of prognosis in patients attended in hospital emergency departments. / Capacidad del biomarcador suPAR para estratificar el pronóstico en pacientes atendidos en servicios de urgencias hospitalarios.

OBJECTIVES: To determine the value of the soluble urokinase-type plasminogen activator receptor (suPAR) for predicting outcomes in emergency department (ED) patients. Secondary objectives were 1) to measure the predictive value of the usual decision points, 2) to identify patients at low risk for mortality who could be safely discharged from the ED, and 3) to measure the correlation between suPAR and other biomarkers. MATERIAL AND METHODS: Prospective observational cohort study of patients attended in the EDs of participating hospitals. We recorded sociodemographic variables, comorbidity, variables related to the acute episode, prognostic markers commonly used in EDs, and suPAR concentration. Outcome variables were the need for hospital admission during the index episode, ED revisits within 90 days, and 90-day mortality. RESULTS: A total of 990 patients with a median (interquartile range) age of 68 (53-81 years) were studied; 50.8% were men. The median suPAR concentration was 3.8 (2.8-6.0) ng/mL, and 112 patients (11.31%) required admission. At 90 days there were 276 revisits (27.9% of the cohort), and 47 patients (4.74%) had died. Mortality was lower (1%) in patients with suPAR concentrations less than 4 ng/mL (52.5%), and fewer of these patients revisited (24.4%) or required hospitalization (20.6%) than patients with suPAR concentrations higher than 6 ng/mL (mortality, 13.5%; revisits, 39.6%; admissions, 56.3%). A suPAR concentration over 6 ng/mL was associated with 90-day mortality and revisits (adjusted hazard ratios and 95% CIs of 4.61 [1.68-12.67] and 1.59 [1.13-2.10]), respectively. The high suPAR concentration was also associated with hospital admission (odds ratio, 1.62 [0.99-2.62]). CONCLUSION: A suPAR concentration of less than 4 ng/mL identifies patients at low risk of 90-day mortality and revisits or need for hospitalization, whereas a suPAR concentration higher than 6 ng/mL is associated with higher risk for these outcomes.

OBJETIVO: Determinar la capacidad del receptor soluble del activador del plasminógeno tipo uroquinasa (suPAR) para la estratificación pronóstica en pacientes atendidos en servicios de urgencias hospitalarios (SUH). Los objetivos secundarios son: 1) medir la capacidad de los `puntos de decisión habituales, 2) identificar una población de bajo riesgo de mortalidad que puede darse de alta de forma segura desde el SUH, y 3) medir la correlación entre suPAR y otros biomarcadores. METODO: Estudio observacional de cohortes prospectivo de pacientes atendidos en SUH. Se registraron variables sociodemográficas, de comorbilidad, datos del episodio agudo, biomarcadores de uso común en urgencias y suPAR. Las variables de resultado fueron la necesidad de ingreso en el episodio índice, reconsulta al SUH y mortalidad a los 90 días. RESULTADOS: Se incluyeron 990 pacientes, la edad fue de 68 (53-81) años, 50,8% eran hombres, la mediana de suPAR fue de 3,8 (2,8-6,0) ng/ml, 112 pacientes (11,31%) requirieron ingreso. En el seguimiento a 90 días hubo 276 reconsultas (27,9%) y 47 pacientes (4,74%) fallecieron. Los pacientes con suPAR 4 ng/ml (52,5%) tenían menor mortalidad (1%), menor reconsulta (24,4%) y menor necesidad de ingreso hospitalario (20,6%), que pacientes con suPAR 6 ng/ml (mortalidad 13,5%, reconsulta 39,6% e ingreso 56,3%). Un suPAR 6 ng/ml mostró una hazard ratio (IC 95%) ajustada de 4,61 (1,68-12,67) para predecir mortalidad a 90 días y de 1,59 (1,13-2,10) para la reconsulta, y una odds ratio de 1,62 (0,99-2,62) para la necesidad de ingreso hospitalario. CONCLUSIONES: Un valor de suPAR 4 ng/ml identifica pacientes con riesgo bajo de mortalidad a 90 días, de reconsulta y de necesidad de ingreso, mientras que los pacientes con suPAR 6 ng/ml tienen mayor mortalidad, reconsulta y necesidad de ingreso.

qSOFA combined with suPAR for early risk detection and guidance of antibiotic treatment in the emergency department: a randomized controlled trial.

BACKGROUND: Sepsis guidelines suggest immediate start of resuscitation for patients with quick Sequential Organ Failure Assessment (qSOFA) 2 or 3. However, the interpretation of qSOFA 1 remains controversial. We investigated whether measurements of soluble urokinase plasminogen activator receptor (suPAR) may improve risk detection when qSOFA is 1. METHODS: The study had two parts. At the first part, the combination of suPAR with qSOFA was analyzed in a prospective cohort for early risk detection. At the second part, the double-blind, randomized controlled trial (RCT) SUPERIOR evaluated the efficacy of the suPAR-guided medical intervention. SUPERIOR took place between November 2018 and December 2020. Multivariate stepwise Cox regression was used for the prospective cohort, while univariate and multivariate logistic regression was used for the RCT. Consecutive admissions at the emergency department (ED) with suspected infection, qSOFA 1 and suPAR ≥ 12 ng/mL were allocated to single infusion of placebo or meropenem. The primary endpoint was early deterioration, defined as at least one-point increase of admission Sequential Organ Failure Assessment (SOFA) score the first 24 h. RESULTS: Most of the mortality risk was for patients with qSOFA 2 and 3. Taking the hazard ratio (HR) for death of patients with qSOFA = 1 and suPAR < 12 ng/mL as reference, the HR of qSOFA = 1 and suPAR ≥ 12 ng/mL for 28-day mortality was 2.98 (95% CI 2.11-3.96). The prospective RCT was prematurely ended due to pandemia-related ED re-allocations, with 91 patients enrolled: 47 in the placebo and 44 in the meropenem arm. The primary endpoint was met in 40.4% (n = 19) and 15.9% (n = 7), respectively (difference 24.5% [5.9-40.8]; odds ratio 0.14 [0.04-0.50]). One post hoc analysis showed significant median changes of SOFA score after 72 and 96 h equal to 0 and - 1, respectively. CONCLUSIONS: Combining qSOFA 1 with the biomarker suPAR improves its prognostic performance for unfavorable outcome and can help decision for earlier treatment. Trial registration EU Clinical Trials Register (EudraCT, 2018-001008-13) and Clinical-Trials.gov (NCT03717350). Registered 24 October 2018.

Intubation Decision Based on Illness Severity and Mortality in COVID-19: An International Study.

OBJECTIVES: To evaluate the impact of intubation timing, guided by severity criteria, on mortality in critically ill COVID-19 patients, amidst existing uncertainties regarding optimal intubation practices. DESIGN: Prospective, multicenter, observational study conducted from February 1, 2020, to November 1, 2022. SETTING: Ten academic institutions in the United States and Europe. PATIENTS: Adults (≥ 18 yr old) confirmed with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and hospitalized specifically for COVID-19, requiring intubation postadmission. Exclusion criteria included patients hospitalized for non-COVID-19 reasons despite a positive SARS-CoV-2 test. INTERVENTIONS: Early invasive mechanical ventilation (EIMV) was defined as intubation in patients with less severe organ dysfunction (Sequential Organ Failure Assessment [SOFA] < 7 or Pao2/Fio2 ratio > 250), whereas late invasive mechanical ventilation (LIMV) was defined as intubation in patients with SOFA greater than or equal to 7 and Pao2/Fio2 ratio less than or equal to 250. MEASUREMENTS AND MAIN RESULTS: The primary outcome was mortality within 30 days of hospital admission. Among 4464 patients, 854 (19.1%) required mechanical ventilation (mean age 60 yr, 61.7% male, 19.3% Black). Of those, 621 (72.7%) were categorized in the EIMV group and 233 (27.3%) in the LIMV group. Death within 30 days after admission occurred in 278 patients (42.2%) in the EIMV and 88 patients (46.6%) in the LIMV group (p = 0.28). An inverse probability-of-treatment weighting analysis revealed a statistically significant association with mortality, with patients in the EIMV group being 32% less likely to die either within 30 days of admission (adjusted hazard ratio [HR] 0.68; 95% CI, 0.52-0.90; p = 0.008) or within 30 days after intubation irrespective of its timing from admission (adjusted HR 0.70; 95% CI, 0.51-0.90; p = 0.006). CONCLUSIONS: In severe COVID-19 cases, an early intubation strategy, guided by specific severity criteria, is associated with a reduced risk of death. These findings underscore the importance of timely intervention based on objective severity assessments.

SuPAR, biomarkers of inflammation, and severe outcomes in patients hospitalized for COVID-19: The International Study of Inflammation in COVID-19.

Severe coronavirus disease 2019 (COVID-19) is a hyperinflammatory syndrome. The biomarkers of inflammation best suited to triage patients with COVID-19 are unknown. We conducted a prospective multicenter observational study of adult patients hospitalized specifically for COVID-19 from February 1, 2020 to October 19, 2022. Biomarkers measured included soluble urokinase plasminogen activator receptor (suPAR), C-reactive protein, interleukin-6, procalcitonin, ferritin, and D-dimer. In-hospital outcomes examined include death and the need for mechanical ventilation. Patients admitted in the United States (US, n = 1962) were used to compute area under the curves (AUCs) and identify biomarker cutoffs. The combined European cohorts (n = 1137) were used to validate the biomarker cutoffs. In the US cohort, 356 patients met the composite outcome of death (n = 197) or need for mechanical ventilation (n = 290). SuPAR was the most important predictor of the composite outcome and had the highest AUC (0.712) followed by CRP (0.642), ferritin (0.619), IL-6 (0.614), D-dimer (0.606), and lastly procalcitonin (0.596). Inclusion of other biomarkers did not improve discrimination. A suPAR cutoff of 4.0 ng/mL demonstrated a sensitivity of 95.4% (95% CI: 92.4%-98.0%) and negative predictive value (NPV) of 92.5% (95% CI: 87.5%-96.9%) for the composite outcome. Patients with suPAR < 4.0 ng/mL comprised 10.6% of the cohort and had a 0.8% probability of the composite outcome. Applying this cutoff to the validation cohort yielded a sensitivity of 93.8% (90.4%-96.7%) and NPV of 95.5% (93.1%-97.8%) for the composite outcome. Among commonly measured biomarkers, suPAR offered stronger discriminatory ability and may be useful in triaging low-risk patients with COVID-19.

Social isolation, loneliness, and inflammation: A multi-cohort investigation in early and mid-adulthood.

Social isolation and loneliness have been associated with poor health and increased risk for mortality, and inflammation might explain this link. We used data from the Danish TRIAGE Study of acutely admitted medical patients (N = 6,144, mean age 60 years), and from two population-representative birth cohorts: the New Zealand Dunedin Longitudinal Study (N = 881, age 45) and the UK Environmental Risk (E-Risk) Longitudinal Twin Study (N = 1448, age 18), to investigate associations of social isolation with three markers of systemic inflammation: C-reactive protein (CRP), interleukin-6 (IL-6), and a newer inflammation marker, soluble urokinase plasminogen activator receptor (suPAR), which is thought to index systemic chronic inflammation. In the TRIAGE Study, socially isolated patients (those living alone) had significantly higher median levels of suPAR (but not CRP or IL-6) compared with patients not living by themselves. Social isolation prospectively measured in childhood was longitudinally associated with higher CRP, IL-6, and suPAR levels in adulthood (at age 45 in the Dunedin Study and age 18 in the E-Risk Study), but only suPAR remained associated after controlling for covariates. Dunedin Study participants who reported loneliness at age 38 or age 45 had elevated suPAR at age 45. In contrast, E-Risk Study participants reporting loneliness at age 18 did not show any elevated markers of inflammation. In conclusion, social isolation was robustly associated with increased inflammation in adulthood, both in medical patients and in the general population. It was associated in particular with systemic chronic inflammation, evident from the consistently stronger associations with suPAR than other inflammation biomarkers.

Overall and inter-individual effect of four different drug classes on soluble urokinase plasminogen activator receptor in type 1 and type 2 diabetes.

AIM: To evaluate the effect of four different drug classes on soluble urokinase plasminogen activator receptor (suPAR), a biomarker active in multiple inflammatory processes and a risk factor for complications, in people with type 1 and type 2 diabetes. METHODS: We conducted post hoc analyses of a randomized, open-label, crossover trial including 26 adults with type 1 and 40 with type 2 diabetes with urinary albumin-creatinine ratio ≥30 and ≤500 mg/g assigned to 4-week treatments with telmisartan 80 mg, empagliflozin 10 mg, linagliptin 5 mg and baricitinib 2 mg, separated by 4-week washouts. Plasma suPAR was measured before and after each treatment. SuPAR change after each treatment was calculated and, for each individual, the best suPAR-reducing drug was identified. Subsequently, the effect of the best individual drug was compared against the mean of the other three drugs. Repeated-measures linear mixed-effects models were employed. RESULTS: The baseline median (interquartile range) plasma suPAR was 3.5 (2.9, 4.3) ng/mL. No overall effect on suPAR levels was observed for any one drug. The individual best-performing drug varied, with baricitinib being selected for 20 participants (30%), followed by empagliflozin for 19 (29%), linagliptin for 16 (24%) and telmisartan for 11 (17%). The individual best-performing drug reduced suPAR by 13.3% (95% confidence interval [CI] 3.7, 22.8; P = 0.007). The difference in suPAR response between the individual best-performing drug and the other three was -19.7% (95% CI -23.1, -16.3; P < 0.001). CONCLUSIONS: We demonstrated no overall effect of 4-week treatment with telmisartan, empagliflozin, linagliptin or baricitinib on suPAR. However, individualization of treatment might significantly reduce suPAR levels.

suPAR links a dysregulated immune response to tissue inflammation and sepsis-induced acute kidney injury.

Acute kidney injury (AKI) secondary to sepsis results in poor outcomes and conventional kidney function indicators lack diagnostic value. Soluble urokinase plasminogen activator receptor (suPAR) is an innate immune-derived molecule implicated in inflammatory organ damage. We characterized the diagnostic ability of longitudinal serum suPAR levels to discriminate severity and course of sepsis-induced AKI (SI-AKI) in 200 critically ill patients meeting Sepsis-3 criteria. The pathophysiologic relevance of varying suPAR levels in SI-AKI was explored in a polymicrobial sepsis model in WT, (s)uPAR-knockout, and transgenic suPAR-overexpressing mice. At all time points studied, suPAR provided a robust classification of SI-AKI disease severity, with improved prediction of renal replacement therapy (RRT) and mortality compared with established kidney biomarkers. Patients with suPAR levels of greater than 12.7 ng/mL were at highest risk for RRT or death, with an adjusted odds ratio of 7.48 (95% CI, 3.00-18.63). suPAR deficiency protected mice against SI-AKI. suPAR-overexpressing mice exhibited greater kidney damage and poorer survival through inflamed kidneys, accompanied by local upregulation of potent chemoattractants and pronounced kidney T cell infiltration. Hence, suPAR allows for an innate immune-derived and kidney function-independent staging of SI-AKI and offers improved longitudinal risk stratification. suPAR promotes T cell-based kidney inflammation, while suPAR deficiency improves SI-AKI.

Challenges facing the clinical adoption of a new prognostic biomarker: a case study.

In this article, we show how a particular biomarker comes into being in an emergency department in a hospital in Copenhagen, Denmark. We explore the contextual becoming of this biomarker, suPAR, through interviews with nurses and physicians and through relational ontology. We find that as a prognostic biomarker suPAR is challenged in it becoming as an object for clinical practice in the emergency department by the power of diagnostic practices and the desire for experience-based scripts that quickly enable the clinician to reach the right diagnosis. Although suPAR is enacted as a promising triage strategy suggesting a low or high risk of disease, the inability to rule out specific diagnoses and producing the notion of secure clinical actions make its non-specificity and prognostic character problematic in clinical practices. Specific diagnostic criteria versus prognostic interpretation and non-specificity risk profiling challenges the way healthcare workers in an emergency department understand the tasks they are set to solve and how to solve them. We discuss how the becoming of suPAR is strengthened through enactments of specificity and engagement in triage strategies and we reflect on it's becoming through new diagnostic practices with the need to accommodate diagnostic ambiguity.

Self-rated health and chronic inflammation are related and independently associated with hospitalization and long-term mortality in the general population.

The subjective indicator of health self-rated health (SRH) and the chronic inflammation biomarker soluble urokinase plasminogen activator receptor (suPAR) are both robust predictors of healthcare use and mortality. However, the possible relationship between SRH and suPAR in the assessment of hospitalization and mortality risk is unknown. We used data from the Danish population-based Inter99 cohort to examine the association between SRH and suPAR and test their individual and combined associations with 2-year risk of acute hospitalization and 5- and 15-year mortality. SRH and serum suPAR levels were measured in 5490 participants (median age 45.1 years, 48.7% men). Poorer SRH was associated with elevated suPAR. In unadjusted analyses, SRH and suPAR were individually associated with higher risks of acute hospitalization and mortality, and both measures remained independently associated with higher risks of hospitalization and 15-year mortality after mutual adjustments. The association of suPAR with mortality was stronger in poorer SRH categories, and when combined, SRH and suPAR could identify different groups of individuals with increased risk of acute hospitalization and mortality. Both SRH and suPAR were independently associated with risk of acute hospitalization and mortality, and different combinations of the two measures could identify different groups of individuals at increased risk.

Increased soluble urokinase plasminogen activator levels modulate monocyte function to promote atherosclerosis.

People with kidney disease are disproportionately affected by atherosclerosis for unclear reasons. Soluble urokinase plasminogen activator receptor (suPAR) is an immune-derived mediator of kidney disease, levels of which are strongly associated with cardiovascular outcomes. We assessed suPAR's pathogenic involvement in atherosclerosis using epidemiologic, genetic, and experimental approaches. We found serum suPAR levels to be predictive of coronary artery calcification and cardiovascular events in 5,406 participants without known coronary disease. In a genome-wide association meta-analysis including over 25,000 individuals, we identified a missense variant in the plasminogen activator, urokinase receptor (PLAUR) gene (rs4760), confirmed experimentally to lead to higher suPAR levels. Mendelian randomization analysis in the UK Biobank using rs4760 indicated a causal association between genetically predicted suPAR levels and atherosclerotic phenotypes. In an experimental model of atherosclerosis, proprotein convertase subtilisin/kexin-9 (Pcsk9) transfection in mice overexpressing suPAR (suPARTg) led to substantially increased atherosclerotic plaques with necrotic cores and macrophage infiltration compared with those in WT mice, despite similar cholesterol levels. Prior to induction of atherosclerosis, aortas of suPARTg mice excreted higher levels of CCL2 and had higher monocyte counts compared with WT aortas. Aortic and circulating suPARTg monocytes exhibited a proinflammatory profile and enhanced chemotaxis. These findings characterize suPAR as a pathogenic factor for atherosclerosis acting at least partially through modulation of monocyte function.

Soluble Urokinase Plasminogen Activator Receptor and Venous Thromboembolism in COVID-19.

Background Venous thromboembolism (VTE) contributes significantly to COVID-19 morbidity and mortality. The urokinase receptor system is involved in the regulation of coagulation. Levels of soluble urokinase plasminogen activator receptor (suPAR) reflect hyperinflammation and are strongly predictive of outcomes in COVID-19. Whether suPAR levels identify patients with COVID-19 at risk for VTE is unclear. Methods and Results We leveraged a multinational observational study of patients hospitalized for COVID-19 with suPAR and D-dimer levels measured on admission. In 1960 patients (mean age, 58 years; 57% men; 20% Black race), we assessed the association between suPAR and incident VTE (defined as pulmonary embolism or deep vein thrombosis) using logistic regression and Fine-Gray modeling, accounting for the competing risk of death. VTE occurred in 163 (8%) patients and was associated with higher suPAR and D-dimer levels. There was a positive association between suPAR and D-dimer (ß=7.34; P=0.002). Adjusted for clinical covariables, including D-dimer, the odds of VTE were 168% higher comparing the third with first suPAR tertiles (adjusted odds ratio, 2.68 [95% CI, 1.51-4.75]; P<0.001). Findings were consistent when stratified by D-dimer levels and in survival analysis accounting for death as a competing risk. On the basis of predicted probabilities from random forest, a decision tree found the combined D-dimer <1 mg/L and suPAR <11 ng/mL cutoffs, identifying 41% of patients with only 3.6% VTE probability. Conclusions Higher suPAR was associated with incident VTE independently of D-dimer in patients hospitalized for COVID-19. Combining suPAR and D-dimer identified patients at low VTE risk. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT04818866.

Soluble urokinase plasminogen activator receptor and decline in kidney function among patients without kidney disease.

Background: Hospitalized patients are at an increased risk of developing kidney disease after discharge, often despite the absence of any clinical indicators during hospitalization. Soluble urokinase plasminogen activator receptor (suPAR) is a marker of systemic chronic inflammation that can be measured from routine blood samples. We determined whether elevated suPAR during hospitalization is associated with a decline in estimated glomerular filtration rate (eGFR) after discharge. Methods: This was a retrospective longitudinal cohort study of patients without detectable kidney disease presenting to the emergency department on two separate occasions during a 3-year period. The association between suPAR and a decline in eGFR was assessed by linear mixed models for repeated measures adjusting for age, sex, C-reactive protein, sodium, diabetes, hypertension and cardiovascular disease. Results: In total, 5124 patients (median age 65.9 years, 51.0% female) were included. The median suPAR was 2.9 ng/mL, the median time to readmission was 144 days and the expected rate of eGFR decline over this period was 5.1 mL/min/1.73 m2/year. Adjusting for other risk factors, patients with suPAR <3, 3-6 or ≥6 ng/mL had an expected eGFR decline of 4.3, 5.2 or 9.0 mL/min/1.73 m2/year, respectively. Similarly, patients with suPAR in the lowest (<2.4 ng/mL), middle (2.4-3.6 ng/mL) or highest (≥3.6 ng/mL) tertile had an expected eGFR decline of 4.2, 4.6 or 6.5 mL/min/1.73 m2/year, respectively. In both cases, a higher suPAR level was significantly and independently associated with a higher rate of eGFR decline (P < .001). Conclusions: A higher suPAR level was associated with accelerated eGFR decline among patients presenting to the emergency department, suggesting that routine suPAR measurements may have utility for the early detection of kidney disease.

Association of Preoperative Basal Inflammatory State, Measured by Plasma suPAR Levels, with Intraoperative Sublingual Microvascular Perfusion in Patients Undergoing Major Non-Cardiac Surgery.

It remains unknown whether chronic systemic inflammation is associated with impaired microvascular perfusion during surgery. We evaluated the association between the preoperative basal inflammatory state, measured by plasma soluble urokinase-type plasminogen activator receptor (suPAR) levels, and intraoperative sublingual microcirculatory variables in patients undergoing major non-cardiac surgery. Plasma suPAR levels were determined in 100 non-cardiac surgery patients using the suPARnostic® quick triage lateral flow assay. We assessed sublingual microcirculation before surgical incision and every 30 min during surgery using Sidestream Darkfield (SDF+) imaging and determined the De Backer score, the Consensus Proportion of Perfused Vessels (Consensus PPV), and the Consensus PPV (small). Elevated suPAR levels were associated with lower intraoperative De Backer score, Consensus PPV, and Consensus PPV (small). For each ng mL−1 increase in suPAR, De Backer score, Consensus PPV, and Consensus PPV (small) decreased by 0.7 mm−1, 2.5%, and 2.8%, respectively, compared to baseline. In contrast, CRP was not significantly correlated with De Backer score (r = −0.034, p = 0.36), Consensus PPV (r = −0.014, p = 0.72) or Consensus PPV Small (r = −0.037, p = 0.32). Postoperative De Backer score did not change significantly from baseline (5.95 ± 3.21 vs. 5.89 ± 3.36, p = 0.404), while postoperative Consensus PPV (83.49 ± 11.5 vs. 81.15 ± 11.8, p < 0.001) and Consensus PPV (small) (80.87 ± 13.4 vs. 78.72 ± 13, p < 0.001) decreased significantly from baseline. In conclusion, elevated preoperative suPAR levels were associated with intraoperative impairment of sublingual microvascular perfusion in patients undergoing elective major non-cardiac surgery.

Acute and Long-Term Treatment With Dapagliflozin and Association With Serum Soluble Urokinase Plasminogen Activator Receptor.

Background: Elevated soluble urokinase plasminogen activator receptor (suPAR) is highly associated with increased risk of diabetic complications. Dapagliflozin is a drug inhibiting the sodium-glucose co-transporter 2 in the kidney to decrease blood glucose, while also decreasing risk of kidney disease, heart failure, and death. Therefore, we have investigated suPAR as a monitor for treatment effect with dapagliflozin in diabetes. Methods: suPAR was measured in two double-blinded randomized clinical cross-over trials. The first trial investigated the effect of a single dose dapagliflozin 50 mg or placebo 12 h after intake, in individuals with type 1 diabetes and albuminuria. The second trial investigated the effect of a daily dose dapagliflozin 10 mg or placebo for 12 weeks, in individuals with type 2 diabetes and albuminuria. suPAR was measured in serum samples taken, in the acute trial, after treatment with dapagliflozin and placebo, and in the long-term trial, before and after treatment with dapagliflozin and placebo. Effect of dapagliflozin on suPAR levels were assessed using paired t-test. Results: 15 participants completed the acute trial and 35 completed the long-term trial. Mean difference in suPAR between dapagliflozin and placebo in the acute trial after 12 h was 0.70 ng/ml (95% CI: 0.66; 1.33, p = 0.49). In the long-term trial the mean difference was 0.06 ng/ml (95% CI -0.15; 0.27, p = 0.57). Conclusion: Based on our findings we conclude that suPAR is not a feasible marker to monitor the effect of treatment with dapagliflozin. Thus, a further search of suitable markers must continue.

IL-1 Mediates Tissue-Specific Inflammation and Severe Respiratory Failure in COVID-19.

Acute respiratory distress syndrome (ARDS) in COVID-19 has been associated with catastrophic inflammation. We present measurements in humans and a new animal model implicating a role in danger-associated molecular patterns. Calprotectin (S100A8/A9) and high-mobility group box 1 (HMGB1) were measured in patients without/with ARDS, and admission calprotectin was associated with soluble urokinase plasminogen activator receptor (suPAR). An animal model was developed by intravenous injection of plasma from healthy or patients with COVID-19 ARDS into C57/BL6 mice once daily for 3 consecutive days. Mice were treated with one anti-S100A8/A9 antibody, the IL-1 receptor antagonist anakinra or vehicle, and Flo1-2a anti-murine anti-IL-1α monoclonal antibody or the specific antihuman IL-1α antibody XB2001 or isotype controls. Cytokines and myeloperoxidase (MPO) were measured in tissues. Calprotectin, but not HMGB1, was elevated in ARDS. Higher suPAR indicated higher calprotectin. Animal challenge with COVID-19 plasma led to inflammatory reactions in murine lung and intestines as evidenced by increased levels of TNFα, IL-6, IFNγ, and MPO. Lung inflammation was attenuated with anti-S100A8/A9 pre-treatment. Anakinra treatment restored these levels. Similar decrease was found in mice treated with Flo1-2a but not with XB2001. Circulating alarmins, specifically calprotectin, of critically ill COVID-19 patients induces tissue-specific inflammatory responses through an IL-1-mediated mechanism. This could be attenuated through inhibition of IL-1 receptor or of IL-1α.

Circulating suPAR associates with severity and in-hospital progression of COVID-19.

BACKGROUND: COVID-19 disease progression is characterized by hyperinflammation and risk stratification may aid in early aggressive treatment and advanced planning. The aim of this study was to assess whether suPAR and other markers measured at hospital admission can predict the severity of COVID-19. METHODS: The primary outcome measure in this international, multi-centre, prospective, observational study with adult patients hospitalized primarily for COVID-19 was the association of WHO Clinical Progression Scale (WHO-CPS) with suPAR, ferritin, CRP, albumin, LDH, eGFR, age, procalcitonin, and interleukin-6. Admission plasma suPAR levels were determined using the suPARnostic® ELISA and suPARnostic® Turbilatex assays. RESULTS: Seven hundred and sixty-seven patients, 440 (57.4%) males and 327 (42.6%) females, were included with a median age of 64 years. Log-suPAR levels significantly correlated with WHO-CPS score, with each doubling of suPAR increasing the score by one point (p < .001). All the other markers were also correlated with WHO-CPS score. Admission suPAR levels were significantly lower in survivors (7.10 vs. 9.63, 95% CI 1.47-3.59, p < .001). A linear model (SALGA) including suPAR, serum albumin, serum lactate dehydrogenase, eGFR, and age can best estimate the WHO-CPS score and survival. Combining all five parameters in the SALGA model can improve the accuracy of discrimination with an AUC of 0.80 (95% CI: 0.759-0.836). CONCLUSIONS: suPAR levels significantly correlated with WHO-CPS score, with each doubling of suPAR increasing the score by one point. The SALGA model may serve as a quick tool for predicting disease severity and survival at admission.