Plasma Glial Fibrillary Acidic Protein, Copeptin, and Matrix Metalloproteinase-9 Concentrations among West African Stroke Subjects Compared with Stroke-Free Controls

Abstract

Measurement of plasma molecular markers among stroke patients has been proposed as an avenue for improving the accuracy of stroke diagnosis. There is paucity of data on the potential role of these markers in resource-limited settings, where the burden of stroke is greatest. To assess the potential diagnostic and prognostic performance of 3 proposed biomarkers for stroke in a resource-constrained setting. Consecutive stroke subjects presenting at a tertiary medical center in Kumasi, Ghana, with radiologically confirmed diagnosis and etiologic subtype information available were recruited along with age- and gender-matched controls in a 2:1 ratio. Plasma concentrations of glial fibrillary acidic protein (GFAP), copeptin, and matrix metalloproteinase-9 (MMP-9) among stroke patients and stroke-free controls were measured in duplicates using enzyme linked immunoassays. Diagnostic and prognostic correlates were assessed using area-under-the-curve (AUC) measures of receiver operator curves and logistic regression analysis, respectively. There were 156 stroke subjects with a mean age of 61.3 years of which 47.4% were females and 74 age- and gender-matched stroke-free controls. Median (interquartile range) time from symptom onset to hospital presentation for care was 7 days (5-11). Diagnostic accuracy of a single measurement of the 3 biomarkers for stroke using AUC (95% confidence interval) plots were as follows: .84 (.77-0.91), P < .0001, for GFAP; .85 (.79-0.92), P < .0001, for copeptin; and .65 (.56-0.73), P = .0003, for MMP-9. None of the biomarkers was associated with stroke severity or mortality. Plasma concentrations of GFAP and copeptin demonstrated stronger associations with stroke occurrence in this West African cohort compared with controls.