From Padasana to Pain Relief: Iyengar Yoga for Chronic Low Back Pain
Abstract & Commentary
By Nancy Selfridge, MD. Dr. Selfridge is Associate Professor of Medicine, Integrative Medicine Department, Ross University School of Medicine, Freeport, Grand Bahama; she reports no financial relationship to this field of study.
Synopsis: Iyengar yoga training and practice was shown by the authors to significantly improve functional disability, pain, and depression in adults with chronic low back pain, compared to a control group receiving standard medical care. The yoga group also demonstrated a trend to reduce pain medicine use compared to the control group.
Source: Williams K, et al. Evaluation of the effectiveness and efficacy of Iyengar yoga on chronic low back pain. Spine 2009;34:2066-2076.
Based on a few studies showing that yoga therapy is helpful for treating chronic low back pain, including a 2005 randomized controlled trial of shorter duration by the same lead study author,1 Williams et al hypothesized that a 24-week program of Iyengar yoga would result in improvements in pain, functional disability, and depression, and in reductions in pain medication usage.
Ninety participants were identified and allocated randomly to an intervention group (n = 43) or a control group (n = 47). The intervention group participated twice-weekly in 90-minute Iyengar yoga classes and were directed to practice 30 minutes of yoga daily at home on nonclass days after being supplied with props, a DVD, and an Iyengar yoga instruction manual. Their compliance was measured by documenting class attendance and by participants submitting weekly reports on the duration and frequency of their home practice. The control group continued self-directed standard medical care without any attempt to regulate treatment received and monthly phone calls were conducted to both groups to collect information about medical care and the use of pain medicine. The control group participants who were adherent to the study requirements were "wait-listed" and offered the yoga classes 6 months after the conclusion of the study.
Four primary outcomes were determined: pain using a visual analogue scale, functional disability using the Oswestry Disability Index, depression using the Beck Depression Inventory, and self-reported medication use. Data were obtained at baseline, 12, 24, and 48 weeks and results for the treatment and control groups were compared in both intention-to-treat and per-protocol analyses for each primary outcome.
The yoga treatment group had statistically significant reductions in functional disability, pain intensity, and depression in both intention-to-treat and per-protocol analyses compared to the control group. A total of 16 study participants did not complete the 24-week protocol. This included 12 from the yoga group, the majority reporting reasons unrelated to the yoga therapy. There was a nonsignificant reduction in pain medication use by both the yoga and control groups over the course of the study, though the yoga group showed a trend for a higher success rate in decreasing pain medication over time. One adverse event was reported during the 6-month post-treatment follow-up period that was not associated with the yoga intervention but with physical therapy.
Low back pain (LBP) is one of the most common presenting problems in primary care practice, yet treating back pain can be frustrating for both patients and physicians. The cost of treating LBP annually is estimated to be as high as $60 billion per year; thus, the authors are correct in calling this a major public health issue.2
Practicing physicians need more tools to manage chronic low back pain. Analysis of evidence of efficacy for chronic pharmacologic treatment, particularly opioid use, is not encouraging. It appears that all analgesics provide similar short-term relief and all have obvious risks of adverse effects. Many patients do not receive or choose evidence-based care. In 2003, a national survey showed that 54% of patients with back or neck pain had used CAM within the last year. Though 80% of episodes of acute low back pain appear to resolve within 6 weeks regardless of treatment, a high rate of recurrence (75%) and chronicity (72%) is the norm.3
Standard medical care (SMC) was not actually defined in this study. According to study criteria, these patients were only prohibited from pursuing chiropractic treatment, massage therapy, Pilates, and acupuncture. Knowing what patients were actually doing in the SMC control group might greatly impact the degree of confidence the authors' conclusions merit. Analysis of research suggests that exercise therapy that incorporates individualized regimens, supervision, stretching, and strengthening may produce the best outcomes.4 Interestingly, this Iyengar yoga intervention appears to meet all of these criteria. Though the asanas were predetermined, participants were instructed to use props on an individual basis to achieve proper positioning and alignment and were closely monitored and guided by their teachers, all typical elements of Iyengar yoga style and practice. It would be interesting to see how this study intervention compares to a non-yoga exercise program that incorporates the same criteria, thus determining if yoga practice, which also integrates breathing techniques and mental focus, offers additive unique benefits. Comparing different styles of yoga practice would also seem to be important in making conclusions about the benefits of specific postures.
The authors noted that the control group also reported improvement in all outcomes over the course of the study and postulated that this might be due to the prompting of monthly follow-up phone calls by the research staff. Chronic pain is a fascinating and still poorly understood phenomenon. Many affective elements appear to factor into the pain experience and can modulate it.3 Certainly, support and attention are believed to modulate pain. It is also possible, though, that the positive anticipation of eventually participating in the yoga classes might be affecting the control group's pain experience. Ultimately, with back pain, some people just get better with the "tincture of time," and perhaps this is what we are seeing.
It was very encouraging to see the compliance rate in this study. There was an 88.5% participation in classes and home practice compliance was 87.1%. Clearly the yoga participants demonstrated high self-efficacy with this level of commitment. Further, at the 6-month follow-up, 67.9% of the participants were continuing home practice an average of 3 days per week. However, a striking finding is that of the 16 dropouts in this study, 75% were from the yoga group, though the majority related problems with scheduling, family illness, and loss of employment. One yoga participant dropped out at 24 weeks due to exacerbation of low back pain, though this was not reported by the authors as an "adverse event." This dropout rate may reflect the challenges of committing to a program that requires a consistent 5.5 hours of devoted practice time on a weekly basis. If a yoga intervention is too difficult a program to access and integrate into one's life, it really does not matter how well it works.
Having a treatment recommendation that demonstrates significant evidence of efficacy, has little risk of harm and a high compliance potential is a huge asset in the management of this challenging problem. Methodological flaws are noteworthy, but the results still suggest specified yoga therapy to be a viable tool in our management armamentarium for chronic low back pain.
1. Williams K, et al. Effect of Iyengar yoga therapy for chronic low back pain. Pain 2005;115:107-117.
2. Wipf J, Deyo RA. Low back pain. Med Clin North Am 1995;79:231-246.
3. Kohatsu W. Low back pain. In: Rakel DP, ed.: Integrative Medicine. Philadelphia, PA: Saunders; 2003.
4. Hayden JA, et al. Systematic review: Strategies for using exercise therapy to improve outcomes in chronic low back pain. Ann Intern Med 2005;142:776-785.