AHA 2018 – Chicago, IL, USA

Effectiveness of a Yoga-Based Cardiac Rehabilitation (yoga-care) Program: A Multi-Centre Randomised Controlled Trial of 4,014 Patients With Acute Myocardial Infarction From India

Presented at the AHA congress 2018 by: Dorairaj Prabhakaran

Introduction and methods

Cardiac Rehabilitation (CR) is a Class I indication in post myocardial infarction (MI) patients and has become an integral part of cardiac care in High Income Countries. In Low-Middle Income Countries, however, CR is virtually non-existent due to its high cost and the need for a multidisciplinary team. Even In high income countries uptake of CR is 25-35% and is particularly poor among the elderly and women who may prefer gentler and simpler approaches. Thus, there is a high unmet need for CR.

In India specifically, there is a need for developing a low-cost, culturally acceptable and effective CR, a need that would be filled by Yoga-CaRe should it prove to be efficacious. CR consists of three components: stress reduction via counselling and medication for depression, physical fitness via exercise and lifestyle changes (smoking cessation, nutrition counselling and other healthy behaviors. Yoga address all three components, by breath control and meditation, yogic postures and developing self-restraint (smoking, alcohol) and stimulating a healthy diet.

The aim of this study was therefore to compare the effectiveness of Yoga based Cardiac Rehabilitation (Yoga-CaRe), with Enhanced Standard Care (ESC) in post-MI patients on cardiac morbidity and mortality and quality of life (QoL). The primary outcomes were time to occurrence of first cardiac event (composite of death, nonfatal MI and stroke) & emergency cardiac admissions, and self-rated QoL (EQ-5D-5L) at 12 weeks. The study was performed at 24 centers across India, and trial duration was 50 months. 3959 participants were randomized within 14 days after acute MI, to Yoga-CaRe or ESC. The Yoga-CaRe intervention consisted of session 1: education on lifestyle (week 1), session 2: meditation and breathing (week 3), sessions 3-8: full yoga training sessions, twice per week (weeks 5-7), sessions 9-13: full yoga training sessions, once per week (week 8-13) and from week 14 onwards: self-practice at home.

Main results

• The first co-primary outcome was not significantly altered by Yoga-CaRe as compared with ESC (6.7% vs. 7.3%, HR: 0.91, 95%CI: 0.72-1.14, P=0.33).
• The components of the primary outcomes were numerically fewer with Yoga-CaRe, but the differences did not reach statistical significance.
• Emergency cardiovascular hospitalizations were not significantly reduced by Yoga-CaRe (2.4% vs. 3.0%, HR; 0.82, 95%CI: 0.56-1.20, P=0.26).
• The Kaplan-Meier curve for CV events showed curves that separated after about 24 months. Less than half the number of events were observed as compared to the initial assumption.
• The per-protocol analysis showed a significantly lower risk of CV events in completers (those who participated in ≥10 sessions, HR: 0.54, 95%CI: 0.38-0.76, log-rank test, P<0.001).
• QoL was improved with Yoga-CaRe as compared with ESC (mean change in EQ-5D VAS Score from baseline to 3 months: 10.7 vs. 9.2, regression coefficient: 1.4, 95%CI: 0.3-2.5, P=0.002).
• The secondary outcome return to pre-infarct daily activities was improved with Yoga-CaRe in the intention-to-treat analysis (unadj regression coefficient: 1.17, 95%CI: 0.11-2.23, P<0.001).

Conclusion

Dr. Prabhakaran concluded that Yoga-CaRe, a yoga based CR, is safe, feasible and significantly improves quality of life and return to pre-infarct daily activities. The clinical outcomes were not statistically significantly different between the two groups, possibly due to inadequate power to detect the planned difference due to lower event rate than estimated. The per-protocol analysis showed Yoga-CaRe program to be efficacious in improving clinical outcomes suggesting a potential dose-response relationship. During the discussion, it was added that nearly half of patients adhered to all sessions.

Thus, Yoga-CaRe has the potential to be an alternative to the conventional CR programs and address the unmet needs of cardiac rehabilitation for patients in low- and middle-income countries.

Discussion

Vera Bittner noted that to date, there was no randomized controlled evidence on the effectiveness of yoga for secondary prevention in CHD. The current study qualified for the warranted high quality randomized controlled trial of yoga. The population received a high rate of antiplatelet therapy and statin therapy, and moderate rates of ACE/ARB and betablocker therapy, similar in both groups.

Potential limitations of the study include that the patients were young and the proportion of women was low. It is unclear whether the results can be translated to MI populations in other settings. The CV event rate was low (about 5% in the first year, 10% over 3 years), hence a limited power to detect differences in outcomes. It is unclear whether the results hold true for sicker patients (both with regard to efficacy and safety). She noted that in the ESC group, fewer contact moments with staff were organized than in the yoga group, which may have affected the QoL measures. The ESC group did not get a physical activity intervention, thus it cannot be known if the observed group differences are yoga-specific, and whether for instance a home-walking program could yield similar results. Adherence to all yoga sessions was limited, which raises the question whether adherence would be worse outside a clinical trial setting. Lastly, no information on adverse events or injuries during yoga practice was presented.

Future studies may focus on how the outcomes of Yoga-CaRe compare to other types of CR programs, both in-center and home-based programs, and how the intervention can be translated to other healthcare settings, other patient populations and different cultures. Moreover, combinations of programs may be envisioned, by integrating Yoga-CaRe into existing protocols.

- Our reporting is based on the information provided at the AHA Scientific Sessions -