Meta - Analysis Of The Efficacy Of Traditional Chinese Medicine In The Elderly With Simple Systolic Hypertension

Introduction:Isolated systolic hypertension (ISH) is a major subtype of senile hypertension. the physiological deterioration with aging makes it even more intractable facing both a over reduction in diastolic blood pressure (DBP) and drug combination associated adverse events when dealing with high systolic blood pressure(SBP). Traditional Chinese herbal medicine (TCM) is considered to be a safe and effective alternative for hypertension. However, its benefits and risks have not been systemically evaluated.Objective:We performed subgroup analyses and meta-analysis to assess the efficacy and safety of the traditional Chinese medicine on ISH.Methods:A search strategy was designed to search all the available literature both and conducted by two authors (Cao and Liu) independently. The data bases included Chinese National Knowledge Infrastructure Databases (CNKI) (1979-2015), the Chinese Science and Technology Periodical Database (VIP) (1989-2015), the Chinese Biomedical Database web (CBM) (1978-2015), the Wan Fang Database (1985-2015), EMBASE (1974-2015), PubMed (1966-2015),and the Cochrane Library (Issue 3,2015). The reference lists of relevant reviews, trials, conference proceedings, databases of ongoing trials were also searched. All the searches ended at August 2015. No limitation on language or publication type was set. Statistical analysis was performed by Cochrane Review Manager 5.3 (Copenhagen, The Nordic Cochrane Centre, The Cochrane Collaboration,2014). Dichotomous data were presented as risk ratio (RR) and continuous variables as the mean difference (MD) with 95% confidence intervals (95%CI). Heterogeneity between studies was evaluated and quantified by Cochran’s Q test and Higgins 12 statistic. Data with low heterogeneity (P>0.10 and I2≤50%) was assessed with a fixed-effects model whereas the other (P<0.10 and I2>50%) was assessed with a random-effects model. If significant inter-study heterogeneity was detected, subgroup analysis was conducted based on possible clinical causes. Various subgroup analyses were performed.Results:A total of 24 studies were included analyzed, including 2096 patients (1058 patients for the intervention group and 1038 for the control group), were evaluated in final analyses. Compared with a conventional therapy used alone, TCM as additional intervention was more effective on systolic blood pressure (MD=-7.00, CI=[-10.89,-3.11], P<0.00001) and significantly diminish the pulse pressure (MD=-7.60, CI=[-13.18,-2.02], P<0.00001). However it showed no additional risk on DBP (MD=1.16, CI= [0.02,2.29], P=0.87). Adverse events were not explicitly reported in most RCTs. Our meta-analysis indicates that traditional Chinese herbal medicine is a promising approach for the elderly with ISH, while the evidence for TCM alone is insufficient. Considering the inherent limitations of the included studies, larger high-quality RCTs with extensive follow-up should be performed to validate our findings in the future.