[Umbrella review of Chinese patent medicines in treatment of hypertension]

Abstract

Hypertension is a major risk factor for cardiovascular diseases. Controlling blood pressure can reduce the incidence of cardiovascular events and mortality. The patients with hypertension are mainly treated with antihypertensive drugs. For the patients who can't achieve the target blood pressure with a single drug, comprehensive treatment strategies become particularly important. Chinese patent medicines are prepared by modern extraction and processing technology based on the basic theory of traditional Chinese medicine(TCM). Due to the stable antihypertensive effect, target organ protection, and synergistic effect with western medicine, Chinese patent medicines are becoming one of the effective options for the treatment of hypertension. At present, there are many systematic reviews on the treatment of hypertension with Chinese patent medicines, which makes it difficult for health policy makers and health service providers to choose the best evidence for the treatment. Umbrella review can integrate multiple systematic reviews to comprehensively assess the quality of evidence and potential bias, thereby providing high-quality evidence-based medicine basis for formulating clinical guidelines and optimizing treatment strategies. In this study, the systematic reviews/Meta-analysis of Chinese patent medicines in the treatment of essential hypertension were systematically searched. Sixty-nine articles were included for the umbrella review. Literature information was extracted, and the corrected covered area(CCA) was calculated to quantitatively evaluate the overlap degree of original studies in systematic reviews/Meta-analysis. The risk of bias in systematic reviews(ROBIS) tool and Cochrane RoB tool 2.0 were used to assess the risk of bias of the included studies. A Measure Tool to Assess Systematic Reviews 2(AMSTAR 2) was used to evaluate the methodological quality of systematic reviews/Meta-analysis. The quality of evidence was evaluated based on the Grade of Recommendations Assessment, Development and Evaluation(GRADE). The results showed that the Chinese patent medicines in the categories of treating wind, resolving stasis, and reinforcing healthy Qi were effective in lowering blood pressure. The Chinese patent medicines for resolving stasis combined with conventional treatment can lower blood pressure and the levels of low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglyceride, and total cholesterol in the treatment of hypertension complicated with coronary heart disease and hypertension complicated with left ventricular hypertrophy. Moreover, the combined therapy can recover the interventricular septal thickness, left ventricular posterior wall thickness, left ventricular mass index, left ventricular end diastolic diameter, and left ventricular ejection fraction in the case of left ventricular hypertrophy. The Chinese patent medicines for resolving stasis and for replenishing Qi and restoring pulse can be used in combination with conventional treatment for hypertension complicated with arrhythmia, which can lower blood pressure while improving the outcome indicators such as the P-wave dispersion of arrhythmia, left atrial diameter, ejection fraction, heart rate, and recurrence time. Due to the heterogeneity, the efficacy evidence obtained by the umbrella review needs to be further verified through precise clinical studies and long-term follow-up.

Keywords: Chinese patent medicine; Meta-analysis; hypertension; quality of evidence; systematic review; umbrella review.