Predictive value of serum transthyretin for outcome in acute ischemic stroke

Introduction The impact of choroid plexus with its blood cerebrospinal fluid barrier in the ischemic stroke pathology is poorly explored. Transthyretin (TTR) is a protein synthesized in liver and just in choroid plexus. Objectives The current study was designed to assess the prognostic value of serum TTR for functional outcome (at the time of hospital discharge) and long-term (one-year) overall mortality in ischemic stroke patients. Patients and methods We conducted a prospective observational study. Patients (n = 81) with acute (< 24 hours of symptoms onset) ischemic stroke consecutively admitted to Stroke Unit were included. An unfavorable outcome was defined as a modified Rankin Scale (mRS) score > 3. The relationships between serum TTR levels and clinical outcome were analyzed using multivariate analysis. One-year mortality was analyzed by Kaplan Meier survival curves stratified by mean value of TTR. Results Compared with patients with mRS <3, patients with an unfavorable outcome at hospital discharge had significantly lower TTR levels on admission (P< 0.0001). In non -survivals serum TTR levels were significantly lower compared with patients who survive one year of observation (P 0.009). Using multivariate analysis, transthyretin emerged as an independent predictor for unfavorable outcome at the day of hospital discharge (adjusted odds ratio = 0.96; 95% CI: 0.9-0.99, P <0.05). A one-year mortality of patients with the lower TTR levels was significantly higher than in patients with TTR levels above mean value (P= 0.02). Conclusions Serum level of TTR at admission was a predictor of functional outcome after ischemic stroke and was also associated with one-year mortality in stroke survivals.