A Meta-analysis Of The Time-effect Of Low-dose Aspirin On Blood Pressure In Hypertensive Patients

Objective :The study was designed to conduct a meta-analysis to assess whether taking low-dose aspirin at bedtime can reduce systolic and diastolic blood pressure compared with taking in the morning in hypertensive patients by a retrieving literature on the effect of low-dose aspirin on blood pressure in hypertensive patients at different times.Therefore,it provides guidance for hypertensive patients to obtain a greater time-benefit ratio by taking aspirin.Materials and Methods:First the search terms and search strategies were developed,and then researcher search the Cochrane Library,Pubmed,Web of Science,China Knowledge Network,VIP database,China Biomedical Literature Database,and Wanfang database by computer network to collect about the effectof taking low-dose aspirin at different times in hypertensive patients.Searchdate is until October 2018.Two researchers independently screen and extract data based on literature inclusion and exclusion criteria,use the Cochrane 5.1 manual that provide an assessment bias risk approach to evalute the quality of the included literature,then the meta-analysis was performed on the included literature using RevMan 5.3 software.Resluts:A total of 7 studies were included in a total of 1102 patients.The results of the meta-analyis show:(1)the effect of taking low-dose aspirin before bedtime on the systolic blood pressure compared with taking in the morning in hypertensive patients: a random effect model was used for all the included literaturs,and the results show(MD-3.74,95%CI(-7.11,-0.38),Z =2.18,P=0.03)that was statistically significant.After excluding Chu Wenshan,Dong Junya,and Liao Chengguang,the results show by using a fixed effect model(MD-2.09,95%CI(-3.84,-0.33),Z =2.33,P=0.02)that was statistically significant?(2)the effect of taking low-dose aspirin before bedtime on the diastolic blood pressure compared with taking in the morning in hypertensive patients: a random effect model was used for all the included literaturs,and the results show(MD-2.63,95%CI(-4.71.-0.55),Z =2.48,P=0.01)that was statistically significant.After excluding Dong Junya and Liao Chengguang,the results show by using a fixed effect model(MD-0.85,,95%CI(-1.91,0.21),Z =1.57,P=0.12)that was no statistical significance,considering Qiuwenshan study that is no mention of how to measure blood pressure may lead to bias in the results,and the results show by the using fixed effect model(MD-0.53,95%CI(-1.64,0.58),Z =0.94,P=0.35)that was no statistical significance.Conclusion:Taking low-dose of aspirin before bedtimie may reduce the systolic blood pressure compared with taking in the morning in hypertensive patients,It is not certain wheter to reduce the diastolic blood pressure.In view of the small sample size and some literature quality restrictions,the intensity of the argument is limited.Therefore,it is necessary to further conduct high-quality,large-sample randomized controlled trials to verify the results of this study,thus providing more reliable evidence for the clinic.