CoRisk Score: Predicting Functional Outcome of Stroke

Determining prognosis following an ischemic stroke is of great importance to patients and their families. Several variables have been recognized as playing a key role in prognosis, particularly age and stroke severity. Treatment with either thrombolysis or mechanical thrombectomy can also influence the prognosis. Researchers aimed to assess whether stroke prognosis can be refined by measuring copeptin, a 39-amino-acid glycopeptide that constitutes the C-terminal part of the arginine-vasopressin precursor. The authors evaluated copeptin plasma levels in a derivation cohort of 319 patients (median age, 75; median NIH Stroke Scale [NIHSS] score, 5; 65% received thrombolysis) and then validated the measure in 783 patients (median age, 71; median NIHSS score, 6; 41% received thrombolysis) from three different hospitals. The outcome of interest was death or disability after stroke, defined as a modified Rankin Scale (mRS) score of 3 to 6. Blood samples of copeptin were drawn within 24 hours after stroke onset for all subjects and before thrombolysis administration if used. The risk model (CoRisk score) included age, NIHSS score, copeptin, and thrombolysis.

In the validation cohort, the median copeptin value was 14.2 pmol/L. At 3 months, 38% had a poor outcome, including death in 15%. For 3-month prediction of disability or death, the area under the receiver operating characteristic curve was 0.82. The reclassification index (i.e., after addition of copeptin in the prediction tool) was 46%.