Copeptin shows prognostic value in acute ischemic stroke
MedWire News: Copeptin is a novel independent prognostic marker in patients with ischemic stroke, suggests research published in the Annals of Neurology.
The study authors believe that the peptide, a fragment of provasopressin, may be able to improve upon currently used risk-stratification schemes for predicting functional outcomes and mortality at 90 days.
Provasopressin is the precursor of vasopressin, a “stress hormone” and potent stimulator of the hypothalamo-pituitary-adrenal axis. Copeptin is released in an equimolar ratio to vasopressin, is more stable in the circulation, and is easy to measure.
In the present study, researchers led by Mirjam Christ-Crain (University Hospital, Petersgraben, Basel, Switzerland) used a new immunoassay to measure copeptin levels in 362 consecutive patients admitted to hospital with an acute ischemic stroke.
They found that copeptin increased in a linear manner with increasing severity of stroke, from 8.6 pmol/l in those with a National Institutes of Health Stroke Scale (NIHSS) score of 0–6, to 30.1 pmol/l in those with an NIHSS score greater than 15.
Most importantly, patients with unfavorable functional outcomes at 90 days (defined as a modified Rankin Scale [mRS] score of 3 or more) had significantly higher admission copeptin levels than those with favorable outcomes (mRS of 2 or less), at 19.4 versus 8.2 pmol/l.
By analyzing the area under the receiver operating characteristic curves (AUC), the researchers found that copeptin was equal or superior to established prognostic markers in discriminating between patients with favorable and unfavorable 90-day outcomes.
Copeptin alone had AUC scores of 0.73 and 0.82 for predicting functional outcome and mortality, respectively, while combining copeptin with the NIHSS score gave AUC scores of 0.79 and 0.89, respectively.
Finally, in multivariate logistic regression analysis, copeptin was an independent predictor of functional outcome, with an adjusted odds ratio of 2.52 per 10 pmol/l increase.
In their discussion the researchers say that copeptin is known to have prognostic value in non-neurologic diseases such as septic shock, acute heart failure, and acute myocardial infarction.
“We assume that the close and reproducible relation of copeptin levels to the degree of activation of the stress axis, and thus disease severity, is the basis of its unique usefulness as a biomarker,” they write.
“Copeptin appears to have interesting potential as a new prognostic biomarker and is a promising candidate also for a multimarker panel. This may allow improved risk-stratification and allocation of targeted therapies for stroke patients in the future.”
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By Joanna Lyford