Yoga, an integral part of Indian culture and heritage, is said to bestow good health － physical, mental and spiritual － on the practitioner. There are various types of yoga involving postural exercises (asanas), breath control (pranayama) and meditation. In one study, the practice of Sahaja yoga, a simple form of meditation, reduced seizures and EEG changes in people with epilepsy. The effect of meditation was attributed to a reduction in the level of stress as evidenced by changes in skin resistance and levels of blood lactate and urinary vanillylmandelic acid.
In this review we have included two unblinded randomised controlled trials (RCTs) recruiting a total of 50 participants (adults) with refractory epilepsy and comparing any type of classical Indian yoga to the control groups receiving no intervention or interventions such as yoga-mimicking exercises or Acceptance and Commitment Therapy. Antiepileptic drugs were continued in all the participants.
The outcomes assessed were: percentage of people rendered seizure free; seizure frequency and duration; and quality of life. Results of the overall efficacy analysis show that yoga treatment was better when compared with no intervention or interventions other than yoga, but no reliable conclusions can be drawn regarding the efficacy of yoga as a treatment for uncontrolled epilepsy. The yoga group showed significant improvement in their quality of life according to the Satisfaction With Life Scale.
Blinding may reduce the observer bias. Physician blinding may be achieved with the outcomes being assessed by a physician who is not involved in the trial. Participant blinding may not be possible, since it would be easy to distinguish whether the intervention given is yoga or not. It would be ideal if the seizure records are maintained by a blinded observer. Seizure frequency outcomes should preferably be expressed as the proportion of individuals seizure free or proportion with more than 50% reduction in seizure frequency, since mean values of seizure frequency are often skewed and difficult to analyse. Seizure duration may be measured in seconds or minutes (per episode or month). Validated quality-of-life measures (disease specific) may indicate whether there is overall improvement in the quality of life as a result of the intervention, besides seizure control.
No reliable conclusions can be drawn at present regarding the efficacy of yoga as a treatment for epilepsy. In addition, evidence to inform outcomes is limited and of low quality. Yoga can be considered as a complex intervention, similar to other forms of complementary and alternative treatments. Yoga can only be an add-on to antiepileptic drugs (AEDs) at the present time and cannot be used as the sole method of intervention. Finally, no reliable evidence was found to support the use of yoga and further trials are needed.
Authors' conclusions:
Study of 50 subjects with epilepsy from two trials reveals possible beneficial effect in control of seizures. Results of the overall efficacy analysis show that yoga treatment was better when compared with no intervention or interventions other than yoga (postural exercises mimicking yoga). There was no difference between yoga and Acceptance and Commitment Therapy. However no reliable conclusions can be drawn regarding the efficacy of yoga as a treatment for uncontrolled epilepsy, in view of methodological deficiencies such as limited number of studies, limited number of participants randomised to yoga, lack of blinding and limited data on quality-of-life outcome. Physician blinding would normally be taken to be the person delivering the intervention, whereas we think the 'physician' would in fact be the outcome assessor (who could be blinded), so that would be a reduction in detection bias rather than performance bias. In addition, evidence to inform outcomes is limited and of low quality. Further high-quality research is needed to fully evaluate the efficacy of yoga for refractory epilepsy.