Analysis On Risk Factors Of Ischemic Stroke Recurrence

Objective Explore the risk factors of ischemic stroke recurrence through hospital-based larger sample historical cohort study, and evaluate the risk of stroke recurrence of patients.Methods Continuity to collect the first attack ischemic stroke cases from the Neurology Department of the Hebei united University Affiliated Hospital between January 1, 2008 and December 31, 2009. Worked out unified questionnaires by Epi Data3.1 general data software, questionnaires contents include: (1) person characteristics; (2) previous medical history; (3) family history of stroke; (4) blood pressure; (5) laboratory report; (6) clinical feature; (7) various score.Took incidence time of patients for follow-up starting point, to patients relapse, lost to follow-up or the last follow-up time for ending.Take phone follow-up and family visit combination form. Follow-up contents included personal history, previous medical history and recurrence. If patients relapse, should understand the specific time. The follow-up was finished in June 30, 2010. According to the research objective, ending events defined as ischemic stroke recurrences. Kaplan - Meier methods were used for recurrence rate analysis. Single factors analysis used t-test and Chi-square. Multi factors analysis used Cox regression. Established the ischemic stroke recurrence prognosis index. Drew ROC curves and determined the cut-off point.Results1 Basic situation: Altogether collected 516 cases complies with the standards cases. 86 cases had missing data, 22 cases had dead in- hospital (Not including for ischemic stroke recurrence death). Eventually 408 cases included in the study. 242(59.3%)patients were men and 166 (40.7%)patients were women.The median age of patients was 61 years (30～91). The median time of onset to admission was 24 hours(1～72). The median time of the length in hospital was 16 days(1～91). The median score of ESRS was 3 points(0～9).In TOAST types, 101(24.8%) patients were small artery occlusion, 226(55.4%)patients were large artery atherosclerosis, 48(11.8%)patients were cardioembolism, 33 (8.1%)patients were stroke of other determined cause/stroke of other undetermined cause.2 Follow-up situation: By the end of follow-up, the median time of follow-up was 14 months(1～30). 26 cases were lost to follow-up, the rate was 5.4%. Examined the basic characteristics between the follow-up group and the lost to follow-up group, the difference was not statistically significant (P>0.05).3 Recurrence situation: By the end of follow-up, 79 cases relapsed, 16 cases died of recurrence(20.3%). The median time of recurrence was 9.5 months(1～25). The recurrence rates of one-year and two-year were 13.4% and 29.6% respectively.4 Risk factors of ischemic stroke recurrence: Single factors and multi factors analysis showed that age (RR=1.674; 95%CI: 1.284～2.183), history of hypertension (RR=2.218; 95%CI: 1.093～4.501), systolic pressure (RR=1.274; 95%CI: 1.001～1.621), total cholesterol (RR=2.877; 95%CI: 1.837～4.506), disease progression (RR=1.809; 95%CI: 1.078～3.037) were the risk factors of ischemic stroke recurrence (P<0.05).5 Establish the ischemic stroke recurrence Cox regression model based on multivariant analysis results: h (t, X) =h0 (t) exp (0.515X₁+0.797X₂+0.242X₃+1.057X₄+0.593X₅) (X₁: age; X₂: history of hypertension; X₃: systolic pressure; X₄: total cholesterol; X₅: disease progression)6 The personal prognosis index(PI)was as the following: PI=0.515X₁+0.797X₂+0.242X₃+1.057X₄+0.593X₅.The smaller the personal prognosis index was, the lower the recurrence risk was; The bigger the personal prognosis index was, the higher the recurrence risk was. 7 Receiver Operating Characteristic (ROC) cures analysis: Take each personal prognosis index as test variables, practical follow-up results as state variables, drew the ROC curves. The area under the curve was 0.827 (95%CI:0.789～0.864), standard error = 0.019, P=0.000.The cut-off point was 2.289. The sensitivity of the model was 0.731, specificity was 0.795. The recurrence possibilities was big when PI≥2.289, it was small when PI<2.289.Conclusions1 Age, history of hypertension, systolic pressure, total cholesterol and disease progression were the main risk factors of ischemic stroke recurrence.2 The individual prognosis index could assess the risk of stroke recurrence for ischemic stroke patients.