Circulating plasma β-globin gene concentrations as a marker of stroke severity in the emergency room

Abstract

Unlike patients with acute coronary syndrome, currentlythere is no simple, accurate blood test that may be used todetermine the severity of stroke or predict mortality andmorbidity in patients presenting to emergency departments.Patients with stroke-like symptoms who presented to anemergency department of a university hospital in HongKong were included in the study. DNA extracted from pa-tients’ plasma was analyzed for the ␤-globin gene with afluorescent-based polymerase chain reaction test. The pri-mary outcome measures were in-hospital and 6-monthmortality and morbidity using the Modified Post-RankinScore. Among the 88 consecutive patients recruited tothe study, 70 (80%) had ischemic stroke, 11 (13%) hadintracerebral hemorrhage, and 7 (8%) had transient isch-emic attacks. Median plasma DNA levels were higher inpatients who died compared with those who survived atdischarge (2,126 vs 1,008 kilogenome-equivalents/L; p ⫽0.0016) and at 6 months (1,979 vs 1,004 kilogenome-equivalents/L; p ⫽ 0.0003). Plasma DNA levels correlatedwith volume of cerebral hematoma (r ⫽ 0.664; p ⫽0.0276). Plasma DNA concentration of greater than 1,400kilogenome-equivalents per liter yielded a sensitivity of100% and a specificity of 74.4% for predicting hospitalmortality after stroke, and the area under the receiver op-erator characteristic curve was 0.888 (95% confidence in-terval, 0.803– 0.945). Plasma DNA level was an indepen-dent risk factor of predicting poor outcome after 6 months.We conclude that plasma DNA levels correlate with strokeseverity and may be used to predict mortality and morbid-ity in emergency rooms.