Age And Sex Affect The Relationship Between Systolic Blood Pressure And Outcome In Acute Ischemic Stroke Treated With Intravenous Thrombolysis:A Secondary Analysis Of INTRECIS Study

Background and purpose: Among patients with acute ischemic stroke,blood pressure is associated with functional outcome.We aimed to explore the effect of sex and age on their association in acute ischemic stroke(AIS)treated with intravenous recombinant tissue plasminogen activator(r-tPA).Methods: Based on the Intravenous Thrombolysis Registry for Chinese Ischemic Stroke within 4.5h onset(INTRECIS)cohort,we retrospectively enrolled AIS patients who received r-tPA with standard dose(0.9 mg/kg,maximum dose 90 mg)with complete blood pressure data,which included baseline systolic blood pressure(SBP 01),SBP at 1hour(SBP 02),SBP at 24 hours(SBP 03)after r-tPA.Furthermore,maximum SBP(SBP max),minimum SBP(SBP min),and mean SBP(SBP mean)were calculated.Good outcome was defined as modified Rankin Scale(mRS)score 0-1 at 90 days,and poor outcome was defined as mRS score 2-6 at 90 days.Baseline and clinical data were compared between the 2 groups.Univariate and multivariate logistic regression analyses were used to explore the effect of different SBP indicators on the 3-month outcomes of AIS patients who received intravenous thrombolysis.Variables with p-values less than0.05 in univariate logistic regression analysis were selected as covariates for multivariate logistic regression analysis(BMI,current drinker,history of stroke,atrial fibrillation,baseline heart rate,Baseline NIHSS and different SBP indicator).A predictive model was constructed to predict poor ontcome at 3 months,and the subject operating characteristic(ROC)curve analysis was used to assess its ability to predict the outcome of patients and to calculate the area under the receiver operator characteristic curve(AUC).The predictive power of different models was assessed.Patients were further classified according to sex and age,and the predictive ability of different SBP indicators was compared among different populations based on age and sex.Forest plots were created using Graphpad Prims 8.0 software.Results: 1593 eligible patients were included in the present study.We found that all SBP indicators were higher in patients with poor outcome vs good outcome at 3 months.Multivariate logistic regression analysis showed that all SBP indicators except baseline SBP were associated with poor outcome with good prediction powers(AUC 0.762-0.766).According to sex stratification,multivariate logistic regression analysis showed that more SBP indicators(SBP 02,SBP 03,SBP min and SBP mean)were associated with poor outcome in women vs men.According to age stratification,multivariate logistic regression analysis showed that all SBP indicators after IVT were associated with poor outcome in patients aged ≥60 years,but none in patients aged < 60 years.Furthermore,all SBP indicators after IVT were associated with poor outcome and in women patients aged ≥60 years,while only SBP 03 in men patients aged < 60 years(aOR 1.139,95%CI1.017-1.276,P = 0.025,SBP03 per 10 mm Hg).Conclusions: Among Chinese stroke patients treated with r-tPA,SBP was associated with outcome,which was affected by age and sex.