A suPAR level below 4 ng/mL can be a useful discharge marker.

suPAR cut-offs <4, between 4-6 and >6 ng/mL can identify acute medical patients who have low, medium, or high risk of 30- and 90-day mortality.

In this new prospective observational study of acute medical patients, conducted at Mikkeli Hospital in Finland, suPAR was measured using the suPARnostic® Turbilatex assay on a Cobas c501 (Roche DiagnosticsLtd) analyzer. Previously suggested cut-offs of suPAR that may indicate low-medium and high risk of 30- and 90-day follow-up were tested.

The results show that suPAR provides significant prognostic patient value. Patients with a suPAR level below 4 ng/mL have a low risk of 30- and 90-day mortality (less than 1%), whereas 90-day mortality reached above 20% in patients with suPAR above 6 ng/mL. This high negative predictive value in patients with suPAR levels below 4 ng/mL can aid in the decision to discharge patients, in combination with other clinical findings.

Important results:

• suPAR, independently of age, sex, and C-reactive protein levels, predicted 30- and 90-day mortality.
• Among the 1747 acute medical patients, almost half had a suPAR level below 4 ng/mL, and the 30- and 90-day risk of mortality in these patients was below 1%.
• Patients with suPAR above 6 ng/mL (1 in 4 patients) had high 90-day mortality of 20%.

Conclusion:

suPAR cut-offs of below 4, between 4-6, and above 6 ng/mL can identify acute medical patients who have a low, medium, or high risk of 30- and 90-day mortality. A suPAR level below 4 ng/mL can thus be useful as a discharge marker. The turbidimetric assay provides fast results that can improve decisions of discharge or admission of acute medical patients.