OBJECTIVES

This review assessed the effects of yoga for treating chronic nonspecific low back pain, compared with no specific treatment, a minimal intervention such as education, or another active treatment, with a focus on pain, function, and adverse events.1

TYPE OF REVIEW

The authors used the search methods recommended by Lefebvre 2011 and Furlan 2015 to search the following databases from inception until March 11, 2016, without restrictions to language or publication status: Cochrane Central Register of Controlled Trials (CENTRAL, which includes the Cochrane Back and Neck Group [CBN] Trials Register) (the Cochrane Library, 2016, Issue 2), MEDLINE (OvidSP, 1946 to March week 1 2016; MEDLINE In-Process & Other Non-Indexed Citations (OvidSP, March 10, 2016; Appendix 1), EMBASE (OvidSP, 1980 to 2016 week 10), Cumulative Index to Nursing and Allied Health Literature (EBSCO, 1981 to March 11, 2016), PsycINFO (OvidSP, 2002 to the second week of March 2016), Allied and Complementary Medicine Database (OvidSP, 1985 to March 2016), CBN Trials Register (Cochrane Register of Studies), Cochrane Complementary Medicine Field Trials Specialized Register (Cochrane Register of Studies Online), IndMED; PubMed; US National Institutes of Health http://ClinicalTrials.gov; and World Health Organization International Clinical Trials Registry Platform.1

RELEVANCE FOR NURSING

Low back pain is a prominent health problem. For many persons, it may last for 3 months or more, and at this point, it is termed chronic. Yoga is sometimes used as a treatment for low back pain. Therefore, nurses need to understand what evidence exists supporting the use of yoga in treating chronic low back pain, so they can advocate the best pain management for their patients.

CHARACTERISTICS OF THE EVIDENCE

The authors included 12 trials (1080 participants) carried out in the United States (7 trials), India (3 trials), and the United Kingdom (2 trials). Studies were unfunded (1 trial), funded by a yoga institution (1 trial), or funded by nonprofit or government sources (7 trials) or did not report on funding (3 trials). Most trials used Iyengar, Hatha, or Viniyoga forms of yoga. The trials compared yoga with no intervention or an exercise intervention (3 trials), a nonexercise intervention such as education (7 trials), or both exercise and nonexercise interventions (2 trials).1

None of the included studies had blinded participants or providers to treatment assignment, and all outcomes were self-reported. Therefore, all studies were at high risk of performance and detection bias, and the authors judged none of the studies to be of high certainty evidence. Some comparisons between yoga and the authors judged nonexercise controls for back-related function and pain produced estimates of moderate certainty. However, most outcomes were downgraded for imprecision because of few participants, and some were downgraded for inconsistency related to heterogeneity between studies, and therefore most comparisons between yoga and nonexercise controls were of low or very low certainty. There was no information on outcomes at other time points. There was no information on adverse events. Studies provided limited evidence on risk of clinical improvement, measures of quality of life, and depression. There was no evidence on work-related disability.

SUMMARY OF KEY EVIDENCE

There is low to moderate certainty evidence that yoga compared with nonexercise controls results in small to moderate improvements in back-related function at 3 and 6 months. Yoga may also be slightly more effective for pain at 3 and 6 months; however, the effect size did not meet predefined levels of minimum clinical importance. It is uncertain whether there is any difference between yoga and other exercise for back-related function or pain, or whether yoga added to exercise is more effective than exercise alone. Yoga is associated with more adverse events than nonexercise controls but may have the same risk of adverse events as other back-focused exercise. Yoga is not associated with serious adverse events. There is a need for additional high-quality research to improve confidence in estimates of effect, to evaluate long-term outcomes, and to provide additional information on comparisons between yoga and other exercise for chronic nonspecific low back pain.1

BEST PRACTICE RECOMMENDATIONS

Yoga appears to be more effective than nonexercise interventions and either as effective or slightly more effective than nonyoga exercise interventions. The authors' review was consistent with a previous systematic review of the safety of yoga in finding that yoga results in more adverse events than psychological or educational interventions but the same number of adverse events as non-yoga exercise.

RESEARCH RECOMMENDATIONS

There is a need for additional research testing yoga versus nonexercise controls to improve the confidence in the estimates of effect. Current trials provide relatively little information on the effects of yoga on pain and on outcomes in the long term. Also, most trials testing yoga versus nonexercise controls have been carried out in well-educated, middle and upper socioeconomic status populations in the United States or United Kingdom. Therefore, there is a need for further trials in a range of populations, including low socioeconomic status populations, older people, and populations with comorbidities. There is also a need for additional methodological research in this research focus, particularly into the potential influence of people's preferences and expectations on outcomes within randomized trials of yoga.1

Reference