Risk of ischemic stroke among newly diagnosed non-valvular atrial fibrillation patients:assessment based on CHADS2 and CHA2DS2-VASc score

ObjectiveTo compare the results of ischemic stroke risk assessment in patients with newly diagnosed non-valvular atrial fibrillation(AF) using CHADS₂(congestive heart failure,hypertension,age≥75 years,diabetes,prior stroke or transient ischemic attack or thromboembolismdoubled) and CHA₂DS₂-VASc(congestive heart failure,hypertension,age≥75 yearsdoubled,diabetes,prior stroke or transient ischemic attack or thromboembolismdoubled,vascular disease,age 65-74 years,sex category) classification schemes for the appropriate application of the schemes among Chinese patients.MethodsWith prospective cohort design,the stroke risk of 143 patients with newly diagnosed non-valvular atrial fibrillation were assessed using CHADS₂ and CHA₂DS₂-VASc score and the results of assessment with the two schemes were compared.ResultsThe average score of CHA₂DS₂-VASc was significantly higher than that of CHADS₂(2.36±1.97 vs.1.51±1.28,P<0.01).Based on the scores of CHADS₂,the proportions of the patients with low,intermediate,and high stroke risk were 32.2%(46/143),29.4%(42／143),and 38.5%(55/143),while based on the scores of CHA₂DS₂-VASc,the proportions were 13.3%(19/143),22.4%(32/143),and 64.3%(92/143),respectively,with a significantly lower proportion of low stroke risk(χ²=4.57,P<0.01)and a significantly higher proportion of high stoke risk(χ²=20.76,P<0.05) for using CHA₂DS₂-VASc compared to using CHADS₂.During the two-year follow-up,the number of stroke incident in the patients with low,intermediate,and high stroke risk assessed with CHADS₂ were 1,2,and 3,whereas the number were 0,0,6 assessed with CHA₂DS₂-VASc,respectively.ConclusionCompared to with CHADS₂,stroke risk assessment with CHA₂DS₂-VASc results in a lower proportion of low risk and a higher proportion of high risk among newly diagnosed Chinese non-valvular AF patients.