Interventional procedure consultation document

Transcranial magnetic stimulation for treating and preventing migraine

Treating and preventing migraine by magnetic stimulation of the brain

Migraine is a severe recurrent headache often associated with nausea and sensitivity to light and sound. Sometimes it may be preceded by an aura (which may include visual disturbances, an imagined unpleasant smell or difficulties with speech).

Transcranial magnetic stimulation can be used during or between migraine attacks. A device is used to administer a magnetic pulse or pulses to the scalp. The pulse or pulses pass throughout the brain and can stop or reduce the severity of migraine attacks or prevent them starting.

 

The National Institute for Health and Care Excellence (NICE) is examining transcranial magnetic stimulation for treating and preventing migraine and will publish guidance on its safety and efficacy to the NHS in England, Wales, Scotland and Northern Ireland. NICE’s Interventional Procedures Advisory Committee has considered the available evidence and the views of specialist advisers, who are consultants with knowledge of the procedure. The Advisory Committee has made provisional recommendations about transcranial magnetic stimulation for treating and preventing migraine.

This document summarises the procedure and sets out the provisional recommendations made by the Advisory Committee. It has been prepared for public consultation. The Advisory Committee particularly welcomes:

• comments on the provisional recommendations
• the identification of factual inaccuracies
• additional relevant evidence, with bibliographic references where possible.

Note that this document is not NICE’s formal guidance on this procedure. The recommendations are provisional and may change after consultation.

The process that NICE will follow after the consultation period ends is as follows.

• The Advisory Committee will meet again to consider the original evidence and its provisional recommendations in the light of the comments received during consultation.
• The Advisory Committee will then prepare draft guidance which will be the basis for NICE’s guidance on the use of the procedure in the NHS in England, Wales, Scotland and Northern Ireland.

For further details, see the Interventional Procedures Programme manual, which is available from the NICE website.

Through its guidance NICE is committed to promoting race and disability equality, equality between men and women, and to eliminating all forms of discrimination. One of the ways we do this is by trying to involve as wide a range of people and interest groups as possible in the development of our interventional procedures guidance. In particular, we aim to encourage people and organisations from groups who might not normally comment on our guidance to do so.

In order to help us promote equality through our guidance, we should be grateful if you would consider the following question:

Are there any issues that require special attention in light of NICE’s duties to have due regard to the need to eliminate unlawful discrimination, advance equality of opportunity, and foster good relations between people with a characteristic protected by the equalities legislation and others?

Please note that NICE reserves the right to summarise and edit comments received during consultations or not to publish them at all where in the reasonable opinion of NICE, the comments are voluminous, publication would be unlawful or publication would otherwise be inappropriate.

 

Closing date for comments: 16 August 2013

Target date for publication of guidance: 27 November 2013

 

 

1                      Provisional recommendations

Transcranial magnetic stimulation (TMS) can be used during the aura preceding a migraine episode or at the start of a migraine episode, with the intention of aborting or reducing the severity of the episode (‘treatment’); or at planned intervals, with the intention of reducing the frequency and/or severity of migraine episodes (‘prevention’).

 

1.1                  Evidence on the efficacy of TMS for the treatment of migraine is limited in quantity and for the prevention of migraine is limited in both quality and quantity. Evidence on its safety in the short and medium term is adequate but there is uncertainty about the safety of long-term or frequent use of TMS. Therefore, this procedure should only be used with special arrangements for clinical governance, consent and audit or research.

 

1.2                  Patient selection should normally be done in specialist headache clinics and the procedure should only be used under the direction of clinicians specialising in the management of headache.

 

1.3                  Clinicians wishing to undertake TMS for treating and preventing migraine should take the following actions.

·      Inform the clinical governance leads in their NHS trusts

·      Ensure that patients understand the uncertainty about the procedure’s safety and efficacy and provide them with clear written information. In addition, the use of NICE’s information for the public [[URL to be added at publication]] is recommended.

·      Audit [URL to audit tool to be added at publication] and review clinical outcomes of all patients having TMS for the treatment and prevention of migraine (see section 7.1).

 

1.4                  NICE encourages further research on TMS for treating and preventing migraine. Studies should describe clearly whether its use is for treatment or prevention. They should report details of patient selection and the dose and frequency of use. Outcome measures should include the number and severity of migraine episodes and quality of life. The development of any neurological disorders (such as epilepsy) in the short or longer term after starting treatment should be documented.

 

 

2                      Indications and current treatments

2.1                  Migraine is a common condition, affecting about 10% of adults. It is characterised by recurrent, pulsatile, unilateral or bilateral headaches that may last from 2 hours to 3 days and are often accompanied by nausea and sensitivity to light and sound. Migraine headache may be preceded by an aura, which can include visual or olfactory disturbances, or difficulties with speech (dysphasia). The International Classification of Headache Disorders (International Headache Society 2004) provides a classification of migraine types.

 

2.2                  Current treatment for migraine aims to prevent or stop episodes and manage symptoms with drugs such as triptans, analgesics and anti-emetics (as recommended in NICE clinical guideline 150). If these fail or are not tolerated, invasive treatments such as nerve blocks, botulinum toxin type A injections (NICE technology appraisal guidance 260) or acupuncture are sometimes used.

 

 

3                      The procedure

3.1                  Transcranial magnetic simulation (TMS) is a non-invasive procedure that aims to treat or prevent migraine episodes in people with acute or chronic migraine (with or without aura). TMS is given using a tabletop or handheld device that delivers a predetermined level of magnetic pulse or pulses to the head.

 

3.2                  The device is placed on the scalp and either single (sTMS) or repeated (rTMS) magnetic pulses are administered. The frequency, intensity, duration and interval times of pulses can be varied as needed. Treatments can be automatically recorded by the device in an integrated headache diary, which can be used to identify headache patterns and triggering factors. Patients may continue to use regular medications including migraine-preventive drugs.  

 

 

4                      Efficacy

This section describes efficacy outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview.

 

4.1                  A multicentre randomised controlled trial (RCT) of 164 patients treated for at least one attack of migraine with aura with a handheld sTMS device (n=82) or with sham stimulation (n=82) reported that pain-free rates 2 hours after stimulation were significantly better with sTMS (39% [32/82]) than with sham stimulation (22% [18/82]; p=0.018). Sustained pain-free response rates (with no recurrence and no rescue drug use) significantly favoured sTMS at 24 hours (29% [24/82] vs 16% [13/82]; p=0.0405) and 48 hours (27% [22/82] vs 13% [11/82]; p=0.0327) after treatment. There were no significant differences in secondary outcomes (headache response at 2 hours, use of rescue drugs, Migraine Disability Assessment [MIDAS] score and consistency of pain relief response) between groups.

 

4.2                  A case series of 51 patients with ‘medically resistant migraine’ using rTMS for prevention reported that 98% (50/51) of patients had a greater than 50% reduction in headache frequency at the end of 1 week and the improvement persisted at follow-up of 4 weeks in 80.4% (41/51) of patients. Headache frequency and severity, functional disability and use of rescue drugs were significantly reduced at all time points (1, 2, 3 and 4 weeks, p<0.0001) but the maximum benefit was observed in the first 2 weeks.

 

4.3                  A case series of 27 patients with migraine comparing low-frequency rTMS (n=14) against sham stimulation (n=13) for prevention reported no significant difference between groups for any reported outcome (including number and duration of migraine attacks, mean pain intensity, and use of analgesics). The ‘within-group’ findings showed a significant decrease in the number of migraine attacks during 8 weeks within the rTMS group from 9.36±2.82 attacks to 6.79±4.28 attacks (p=0.007), and a non-significant decrease within the sham group (numbers not reported; p=0.216). There was a significant reduction of migraine days during 8 weeks in both rTMS and sham groups (from 17.69±11.63 days to 13.15±9.27 days [p=0.012] and from 14.36±5.07 days to 9.50±6.80 days [p=0.006] respectively). The rTMS group showed a significant reduction of migraine hours during 8 weeks from 125.93±80.31 hours to 85.36±72.27 hours, p=0.035; the difference was not significant in the sham group (numbers not reported; p=0.080).

 

4.4                  The specialist advisers listed additional efficacy outcomes as complete resolution of a migraine attack, reduction in headache severity, and improvement in associated symptoms, disability and quality of life.

 

 

5                      Safety

This section describes safety outcomes from the published literature that the Committee considered as part of the evidence about this procedure. For more detailed information on the evidence, see the overview.

 

5.1                  No device-related serious adverse events were reported in the RCT of 164 patients.

 

5.2                  Slight ‘unsustained’ dizziness (n=1), drowsiness (n=1) and tiredness (n=2) were reported in a case series of 42 patients after treatment with low- or high-intensity transcranial magnetic stimulation (TMS). None of these events recurred or required medical attention.

 

5.3                  Amyostasia (muscle tremor causing difficulty in standing, n=1), irritability (n=1), ‘vigorous dreams’ (n=1) and phonophobia (n=1) were reported after rTMS treatment in the case series of 27 patients.

 

5.4                  Discomfort during the first session of rTMS of 2.42±0.74 (assessed using a 0–5 face pain scale where higher scores indicate greater pain) was 1.81±0.70 in the second session and 1.37±0.68 in the third session in the study of 51 patients.

 

5.5                  The specialist advisers listed transient muscle contraction, neuralgia at the stimulation site and hearing impairment during rTMS as additional anecdotal adverse events. The specialist advisers considered theoretical adverse events to include local scalp irritation, mood disorders, cognitive impairment, triggering of epilepsy during treatment and ‘kindling’ leading to seizures. One adviser raised the theoretical possibility of ‘permanent neural changes’ with prolonged use of rTMS.

 

 

6                      Committee comments

6.1                  The Committee noted that there is uncertainty about the optimal dose of TMS for both treatment and prevention of migraine, and the optimal frequency of use for prevention.

 

6.2                  The Committee noted variation among the published studies in the indications for TMS and the treatment parameters used. This variation made evaluation complex and underpinned the recommendation in 1.4 for future studies to include about clear descriptions of indications and treatment regimes.

 

6.3                  The Committee noted that TMS is not intended to provide a cure for migraine and that reduction in symptoms may be modest. It recognised the importance of informing patients about these considerations.

6.4                  The Committee noted the absence of evidence on the safety of long-term use of TMS, although there are currently no reports of the procedure causing harm in the long term. The recommendation in 1.4 about documenting neurological disorders in the long term is based on the lack of information about possible long-term effects of the procedure.

 

 

7                      Further information

7.1                  This guidance requires that clinicians undertaking the procedure make special arrangements for audit. NICE has identified relevant audit criteria and is developing an audit tool (which is for use at local discretion), which will be available when the guidance is published.

_{Personal data will not be posted on the NICE website. In accordance with the Data Protection Act names will be anonymised, other than in circumstances where explicit permission has been given.}

 _{It is the responsibility of consultees to accurately cite academic work in order that they can be validated.}

 

 

Bruce Campbell

Chairman, Interventional Procedures Advisory Committee

July 2013