Yoga for epilepsy

Review question
This review assessed the use of yoga as a treatment for control of epilepsy.

Background
Epilepsy is a disorder in which recurrent seizures are caused by abnormal electrical discharges in the brain. Most seizures can be controlled by antiepileptic drugs (AEDs) but sometimes seizures develop which are resistant to those drugs. People may also wish to try non-drug treatments such as yoga. Between 25% and 40% of people with epilepsy treated with AEDs have uncontrolled seizures, experience adverse effects from medication, suffer from stigmatisation and have a higher degree of psychiatric disorders as compared with people with other chronic illnesses. For those who have epilepsy and related problems it is important to develop, evaluate, and implement a complementary treatment model in the everyday treatment of epilepsy.

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.

Results
For this update, we did not identify any new studies to add, and thus the conclusions remain unchanged. The review 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.

Conclusions
No reliable conclusions can be drawn at present regarding the efficacy of yoga as a treatment for epilepsy. In addition, quality of the 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 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.

The evidence is current to 3 January 2017.

Authors' conclusions: 

A study of 50 subjects with epilepsy from two trials reveals a 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.

Since we did not find any new studies, our conclusions remain unchanged.

Read the full abstract...
Background: 

This is an updated version of the original Cochrane Review published in the Cochrane Library, Issue 5, 2015.

Yoga may induce relaxation and stress reduction, and influence the electroencephalogram and the autonomic nervous system, thereby controlling seizures. Yoga would be an attractive therapeutic option for epilepsy if proved effective.

Objectives: 

To assess whether people with epilepsy treated with yoga:

(a) have a greater probability of becoming seizure free;
(b) have a significant reduction in the frequency or duration of seizures, or both; and
(c) have a better quality of life.

Search strategy: 

For this update, we searched the Cochrane Epilepsy Group Specialized Register (3 January 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 12) in the Cochrane Library (searched 3 January 2017), MEDLINE (Ovid, 1946 to 3 January 2017), SCOPUS (1823 to 3 January 2017), ClinicalTrials.gov (searched 3 January 2017), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (searched 3 January 2017), and also registries of the Yoga Biomedical Trust and the Research Council for Complementary Medicine. In addition, we searched the references of all the identified studies. No language restrictions were imposed.

Selection criteria: 

The following study designs were eligible for inclusion: randomised controlled trials (RCT) of treatment of epilepsy with yoga. The studies could be double-, single- or unblinded. Eligible participants were adults with uncontrolled epilepsy comparing yoga with no treatment or different behavioural treatments.

Data collection and analysis: 

Two review authors independently assessed the trials for inclusion and extracted data. The following outcomes were assessed: (a) percentage of people rendered seizure free; (b) seizure frequency and duration; (c) quality of life. Analyses were on an intention-to-treat basis. Odds ratio (OR) with 95% confidence intervals (95% Cls) were estimated for the outcomes.

Main results: 

We did not identify any new studies for this update, therefore the results are unchanged.

For the previous version of the review, the authors found two unblinded trials in people with refractory epilepsy. In total these two studies included 50 people (18 treated with yoga and 32 to control interventions). Antiepileptic drugs were continued in all the participants. Baseline phase lasted three months in both studies and treatment phase from five weeks to six months in the two trials. Randomisation was by roll of a die in one study and using a computerised randomisation table in the other one but neither study provided details of concealment of allocation and were rated as unclear risk of bias. Overall, the two studies were rated as low risk of bias (all participants were included in the analysis; all expected and pre-expected outcomes were reported; no other sources of bias).

The overall ORs with 95% CI were as follows: (i) seizure free for six months — for yoga versus sham yoga the OR was 14.54 (95% CI 0.67 to 316.69) and for yoga versus 'no treatment' group it was 17.31 (95% CI 0.80 to 373.45); for Acceptance and Commitment Therapy (ACT) versus yoga the OR was 1.00 (95% Cl 0.16 to 6.42); (ii) reduction in seizure frequency — the mean difference between yoga versus sham yoga group was −2.10 (95% CI −3.15 to −1.05) and for yoga versus 'no treatment' group it was −1.10 (95% CI −1.80 to −0.40); (iii) more than 50% reduction in seizure frequency — for yoga versus sham yoga group, OR was 81.00 (95% CI 4.36 to 1504.46) and for the yoga versus 'no treatment' group it was 158.33 (95% CI 5.78 to 4335.63); ACT versus yoga OR was 0.78 (95% Cl 0.04 to 14.75); (iv) more than 50% reduction in seizure duration — for yoga versus sham yoga group OR was 45.00 (95% CI 2.01 to 1006.75) and for yoga versus 'no treatment' group it was 53.57 (95% CI 2.42 to 1187.26); ACT versus yoga OR was 0.67 (95% Cl 0.10 to 4.35).

In addition in Panjwani 1996 the authors reported that the one-way analysis of variance revealed no statistically significant differences between the three groups. A P-Lambda test taking into account the P values between the three groups also indicated that the duration of epilepsy in the three groups was not comparable. No data were available regarding quality of life. In Lundgren 2008 the authors reported that there was no significant difference between the yoga and ACT groups in seizure-free rates, 50% or greater reduction in seizure frequency or seizure duration at one-year follow-up. The yoga group showed significant improvement in their quality of life according to the Satisfaction With Life Scale (SWLS) (P < 0.05), while the ACT group had significant improvement in the World Health Organization Quality of Life-BREF (WHOQOL-BREF) scale (P < 0.01).

Overall, we assessed the quality of evidence as low; no reliable conclusions can be drawn at present regarding the efficacy of yoga as a treatment for epilepsy.