Review: Beyond conventional therapies: Complementary and alternative medicine in the management of hypertension: An evidence-based review

Hypertension is one of the major causes of morbidity and mortality. Worldwide, Hypertension is estimated to cause 7.5 million deaths, about 12.8% of the total of all deaths. This accounts for 57 million disability adjusted life years (DALYS) or 3.7% of total DALYS. This led WHO to set a target of 25% reduction in prevalence by 2025. To reach that, WHO has adopted non-conventional methods for the management of hypertension? Despite worldwide popularity of such non-conventional therapies, only small volume of evidence exists that supports its effectiveness. This review attempted to make a critical appraisal of the evidence, with the aim to (1) describe the therapeutic modalities frequently used, and (2) review the current level of evidence attributable to each modality. Databases from Cochrane Library, MEDLINE, PUBMED, and EMBASE were searched from 2005-2015. A total of 23 publications have been identified and selected. Out of these, 15 systematic reviews and/or meta-analysis of RCTs, 5 RCTs, 1 non-RCT, and 2 observational studies without control. Among those 23 publications, therapeutic modalities identified are: fish oil, qigong, yoga, coenzyme Q10, melatonin, meditation, vitamin D, vitamin C, monounsaturated fatty acids, dietary amino-acids, chiropractic, osteopathy, folate, inorganic nitrate, beetroot juice, beetroot bread, magnesium, and L-arginine. The followings were found to have weak or no evidence: fish oil, yoga, vitamin D, monounsaturated fatty acid, dietary amino-acids, and osteopathy. Those found to have significant reduction in blood pressure are: magnesium, qigong, melatonin, meditation, vitamin C, chiropractic, folate, inorganic nitrate, beetroot juice and L-arginine. Coenzyme Q10on the other hand, showed contradicting results were some studies found weak or no effect on blood pressure while others showed significant blood pressure reduction effect. By virtue of the research designs and methodologies, the evidence contributed from these studies is at level 1. Results from this review suggest that certain non-conventional therapies may be effective in treating hypertension and improving cardiac function and therefore considered as part of an evidence-based approach.