Using suPAR as a Clinical Aid

Risk evaluation in hospital wards and Emergency Departments (EDs) is critical in order to detect early signs of clinical deterioration and enable a timely and appropriate clinical intervention.

The national early warning score (NEWS) and similar vital sign-based track-and-trigger systems are commonly used to monitor patients’ clinical progress and is carried out in-hospital risk assessment of acutely and critically ill patients (1, 2).
Use of track-and-trigger systems has been found to reduce unexpected in-hospital mortality (3). However, these scores based on clinical signs have limitations in predicting the course of disease including the case fatality rate [4].

In an editorial, Koch & Tacke, put forward their theory about how the amount of suPAR in blood measurements from patients can be used as a tool to prioritize emergency patients [5].
Uusitalo-Seppälä and co-workers conducted a large single-centre prospective study including 539 consecutive patients with suspected infection, in which suPAR was measured at admission to the ED [6]. suPAR levels were strong predictors of 28-day, 90-day, and even 1-year case fatality and allowed a better risk stratification compared to classical inflammatory markers such as procalcitonin, interleukin-6, or C-reactive protein [7] (Fig. 1b).

Koch and Tacke continues “A prognostic cut-off value of suPAR concentration could be applicable to all medical patients in the ED, even those without suspected infection, which would indeed make risk stratification in the ED’s suPAR’ easy” [3].

The observation was later confirmed in another study of acute medical patients. The study found that suPAR is strongly associated with disease severity, readmission, and mortality after adjusting for all other risk factors, meaning that suPAR adds information to established prognostic indicators. While patients with low suPAR levels have low risk of readmission and mortality, patients with high suPAR levels have a high risk of adverse events [8].

Figure 1 Koch A. & Tacke F, 2012

  1. Royal College of Physicians: National Early Warning Score (NEWS) – Standardising the assessment of acute-illness severity in the NHS. Report of a working party. 2012
  2. Smith GB, Prytherch DR, Meredith P, et al.: The ability of the National Early Warning Score (NEWS) to discriminate patients at risk of early cardiac arrest, unanticipated intensive care unit admission, and death. Resuscitation 2013; 84:465–470
  3. Bunkenborg G, Samuelson K, Poulsen I, et al.: Lower incidence of unexpected in-hospital death after interprofessional implementation of a bedside track-and-trigger system. Resuscitation 2014; 85:424–430
  4. 4:Challen K & Goodacre SW.Predictive scoring in non-trauma emergency patients: as coping review. Emerg Med J. 2011;28:827–37.
  5. Koch A. & Tacke F, Editorial Comment: Risk stratification and triage in the emergency department: has this become ‘suPAR’ easy? J Intern Med. 2012, 272; 243–246.
  6. Uusitalo-Seppälä R et al., Soluble urokinase-type plasminogen activator receptor in patients with suspected infection in the emergency room: a prospective cohort study, J Intern Med. 2012 Sep;272(3):247-56.
  7. Eugen-Olsen J. et al. suPAR – a future risk marker, J Intern Med. 2011;270:29–31.
  8. Rasmussen LJ et al, Soluble urokinase plasminogen activator receptor (suPAR) in acute care: a strong marker of disease presence and severity, readmission and mortality. A retrospective cohort study. Emerg Med J. 2016 Nov;33(11):769-775.