Validation of a proteomic biomarker panel to diagnose minor-stroke and transient ischaemic attack: phase 2 of SpecTRA, a large scale translational study

Abstract

OBJECTIVE: To validate our previously developed 16 plasma-protein biomarker panel to differentiate between transient ischaemic attack (TIA) and non-cerebrovascular emergency department (ED) patients.

METHOD: Two consecutive cohorts of ED patients prospectively enrolled at two urban medical centers into the second phase of SpecTRA study (training, cohort 2A, n = 575; test, cohort 2B, n = 528). Plasma samples were analyzed using liquid chromatography/multiple reaction monitoring-mass spectrometry. Logistic regression models which fit cohort 2A were validated on cohort 2B.

RESULTS: Three of the panel proteins failed quality control and were removed from the panel. During validation, panel models did not outperform a simple motor/speech (M/S) deficit variable. Post-hoc analyses suggested the measured behaviour of L-selectin and coagulation factor V contributed to poor model performance. Removal of these proteins increased the external performance of a model containing the panel and the M/S variable.

CONCLUSIONS: Univariate analyses suggest insulin-like growth factor-binding protein 3 and serum paraoxonase/lactonase 3 are reliable and reproducible biomarkers for TIA status. Logistic regression models indicated L-selectin, apolipoprotein B-100, coagulation factor IX, and thrombospondin-1 to be significant multivariate predictors of TIA. We discuss multivariate feature subset analyses as an exploratory technique to better understand a panel’s full predictive potential.

Keywords:

• TIA
• transient ischaemic attack
• TIA biomarkers
• stroke biomarkers
• stroke proteomic
• plasma biomarkers

Disclosure statement

CHB is the CSO of MRM Proteomics, Inc. The other authors report no conflict of interest.

Additional information

Funding

Funding for this study was provided by Genome British Columbia [4125-Penn], Genome Alberta [4125-Penn], and Genome Canada [4125-Penn]. The funding agencies had no role in the design of the study and collection, analysis, interpretation of data or writing of this manuscript. AMJ and CHB are grateful to Genome Canada and Genome British Columbia for financial support for the University of Victoria-Genome BC Proteomics Centre (project codes 204PRO for operations and 214PRO for technology development). CHB is also grateful for support from the Leading Edge Endowment Fund (University of Victoria), and from the Segal McGill Chair in Molecular Oncology at McGill University (Montreal, Quebec, Canada). CHB is also grateful for support from the Warren Y. Soper Charitable Trust and the Alvin Segal Family Foundation to the Jewish General Hospital (Montreal, Quebec, Canada)