Yoga as a nonpharmacological alternative or complementary therapy for hypertension

Hypertension is an important risk factor for heart disease and stroke. Treatment of hypertension reduces this risk. The Healthy People 2020 objective is to increase the proportion of adults with high blood pressure whose blood pressure is under control. Prevalence of hypertension in the United States based on the data from NHANES 2007-2008 indicate 29% people have hypertension defined as systolic blood pressure ≥ 140 mm Hg or diastolic blood pressure ≥ 90 mm Hg. Blood pressure was controlled in approximately 50.1% of all patients with hypertension based on NHANES 2007-2008 data. Not all patients accept pharmacological therapy. The purpose of this study was to examine whether yoga is beneficial as a nonpharmacological alternative or complementary therapy for hypertension. The method used in this study was a systematic qualitative review of interventions obtained from MEDLINE, CINAHL, & ERIC databases. The criteria for including studies were: publication in English language, publication between 1975 and 2010, studies that measured blood pressure as an outcome, and studies that used yoga (from any school) as an intervention. A total of 16 articles met the criteria with one study reporting two interventions. Eight interventions were from India, five from United Kingdom, three from United States, and one from Thailand. Only five interventions used randomized controlled trials. All the interventions have shown statistically significant beneficial effects of yoga on hypertension. However several methodological limitations such as weak designs, small sample sizes etc. were identified in the conduct of the intervention trials which future interventions must consider.