Study of the effect of yoga training on diffusion capacity in chronic obstructive pulmonary disease patients: A controlled trial

Patients of chronic obstructive pulmonary disease (COPD) are at high risk for depression and anxiety. Yoga techniques are suited for promoting relaxation, psycho-emotional stability and exercise tolerance. Studies showing the effect of yoga in diffusion capacity are not available; hence this study was planned. The study was conducted on 60 diagnosed stable mild-to-moderate COPD patients in the age group of 30-60 years, of either sex, in the department of physiology. Patients were taken from Guru Teg Bahadur Hospital, Delhi and divided into two groups: Control and the yoga group. Both the groups were on conventional drug therapy. Subjects from the Yoga group was called to cardiopulmonary laboratory daily for 21 days and then weekly for the compliance. Yoga instructor taught them the technique of pranayama and various postures every day. They practiced yoga at home for 2 months for 45 min in the mornings. Diffusion capacity was recorded by using computerized Medisoft instrument (HYPAIR compact), in both the groups before and after 2 months. Statistical analysis showed significant improvement in TLCO of the yoga group. Transfer factor of lung for carbon monoxide i.e. TLCO in mild COPD increased from 17.61 ± 4.55 to 19.08 ± 5.09 ml/mmHg/min, and in moderate COPD it increased from 14.99 ± 4.02 to17.35 ± 3.97 ml/mmHg/min. It was concluded that yogic breathing exercises improve diffusion capacity. They are beneficial to COPD patients and they can be used as an adjunct therapy with the conventional medical therapy.