Washington D.C. [USA], Dec. 8 : Practicing yoga for one hour daily can reduce blood pressure in people with prehypertension, says a new study conducted by Indian researchers.
The study was presented at the 68th Annual Conference of the Cardiological Society of India (CSI) in Kochi, India.
"Patients with prehypertension (slightly elevated blood pressure) are likely to develop hypertension (high blood pressure) unless they improve their lifestyle," said lead author Dr Ashutosh Angrish, a cardiologist at Sir Gangaram Hospital in Delhi, India.
"Both prehypertension and high blood pressure increases the risk of heart attack, stroke and heart failure," Angrish added.
"Our research suggests that patients with prehypertension should be advised to practice hatha yoga (a combination of asanas, pranayam and meditation) for one hour daily.
It may prevent the development of hypertension and in addition give a sense of well-being," he explained.
Hypertension is defined as a systolic blood pressure (BP) 140 mmHg and/or diastolic BP 90 mmHg, while prehypertension is a systolic BP 120-139 mmHg or a diastolic BP 80-89 mmHg.
The researchers investigated the impact of hatha yoga -- a system of physical exercises and breathing control used in yoga -- on blood pressure in 60 patients with prehypertension, who were otherwise healthy.
The average age of the participants was 56 years in the yoga group and 52 years in the control group. Briefly, the patients were randomised to two groups of 30 each, to assess the effect of three months of yoga plus conventional lifestyle changes versus conventional lifestyle changes alone on 24 hour ambulatory blood pressure.
Yoga included stretching exercises (asanas), breath control (pranayam) and meditation. It was taught by a yoga instructor for one month and then patients subsequently followed it at home. Yoga practice was for one hour every day. Conventional lifestyle changes consisted of moderate aerobic exercise, diet, and smoking cessation. The 24 hour mean BP at baseline was 130/80 mmHg in the yoga group and 127/80 mmHg in the control group.
The study found that in the yoga group, both 24 hour diastolic BP and night diastolic BP significantly decreased by approximately 4.5 mmHg and 24 hour mean arterial pressure significantly decreased by around 4.9 mmHg.
The control group did not show any significant change in blood pressure. "Although the reduction in blood pressure was modest, it could be clinically very meaningful because even a 2 mmHg decrease in diastolic BP has the potential to decrease the risk of coronary heart disease by six percent and the risk of stroke and transient ischaemic attack by 15 percent," Dr Angrish explained.