Abstract
Background
Many people suffering from migraine combine pharmacological and non-pharmacological treatments. The purpose of this systematic review is to provide an updated guideline for some widely used non-pharmacological treatment options for migraine.
Methods
We conducted a systematic literature review of randomized studies of adults with migraine treated with manual joint mobilisation techniques, supervised physical activity, psychological treatment, acupuncture and patient education. The main outcomes measured were days with headache and quality of life. Recommendations were formulated based on the Grade of Recommendation, Assessment, Development and Evaluation (GRADE) approach including patient preferences based on expert opinion and questionnaire data.
Results
The overall level of certainty of the evidence was low to very low. Manual therapy techniques and psychological treatment did not change the studied outcomes. Supervised physical activity might have a positive impact on quality of life, acupuncture on headache frequency, intensity, quality of life and the use of attack-medicine. Patient education might improve self-rated health and quality of life and increase the number of well-informed patients.
Conclusion
Based on observed effects, the lack of serious adverse events, and patients’ preferences, we make weak recommendations for considering the investigated interventions as a supplement to standard treatment.
Keywords
Introduction
Migraine, episodic and chronic, is a debilitating headache disorder affecting about 20% of the Danish population (1). It is the most prevalent cause of years lived with disability in the age group 15-49 years (2,3).
The standard therapy for migraine consists of acute pharmacological treatment of the migraine attack and, depending on the attack frequency, preventive headache medication. Acute treatment comprises simple analgesics and migraine specific drugs like triptans, combined with antiemetic drugs (4). Antihypertensive and anti-epileptic drugs are used for preventive treatment (5). Botulinum toxin and Calcitonin-Gene-Related Peptide/-Receptor (CGRP/-R)-antibodies are additional options for episodic and chronic migraine with variable availability depending on the evaluations of the health authorities of the respective countries (6,7).
Tolerability remains a clinical problem for many prophylactics, as side effects often lead to discontinuation and patients seek out alternative, non-pharmacological treatment options. Based on patient preferences and shortcomings of standard pharmacological treatment, clinicians, policymakers, and patients turn to the vast variety of available non-pharmacological treatments including physical interventions (physiotherapy, exercises, manual therapy), acupuncture, psychological and educational interventions.
The spectrum of physical interventions is large and comprises exercises aiming at the improvement or maintenance of one or more components of physical fitness (e.g. neck shoulder exercises as well as aerobic exercises, including high-intensity interval training and moderate continuous training), muscle relaxation and contract-relax techniques. Manual joint mobilising treatment, osteopathic manipulative treatment, chiropractic spinal manipulative treatment, and reflexotherapy are other examples illustrating the diversity of the techniques (8). Commonly applied acupunctural techniques comprise trigger point acupuncture, electro-acupuncture, and dry needling (9,10). In addition, various different psychological treatment approaches (autogenic training, systematic relaxation, mindfulness-based cognitive behavioral therapy, cognitive behavioral therapy, behavioral sleep modification), patient education, self-care nursing, Yoga, biofeedback-assisted diaphragmatic breathing, and many other interventions have been used to supplement medical treatment (11,12).
Some specialized headache clinics in Denmark have developed interdisciplinary treatment schedules (“headache schools”) comprising physiotherapeutic, psychological, and educational interventions supplementing the ongoing medical treatment (13). Currently, these interdisciplinary treatment schedules are usually not part of the primary care. However, an implementation of the large variety of available interventions will require standardised and evidence-based procedures, relevant professional staff, and adequate financial resources. In 2012, the National Clinical Guideline Centre, commissioned by the National Institute for Health and Care Excellence (NICE), published a clinical guideline for the management of primary headache disorders (NICE CG150), which found some evidence on the effect of acupuncture but no evidence on the use of manual or psychological therapies, education, or exercise (14). However, in the same year, the guideline committee of the Italian Society for the Study of Headaches (SISC) published an updated diagnostic and therapeutic guideline for primary headaches in adults concluding that there was most evidence for biofeedback and acupuncture in the preventive treatment of migraine (15). The discrepancies between these two guidelines are likely a result of different methodological approaches, including different search strategies and quality assessment of the identified evidence.
Thus, there is a need to establish evidence-based guidelines on the non-pharmacological treatment of migraine to update and standardise the non-pharmacological interventions, to guide health care professionals and to integrate the non-pharmacological treatment in the treatment of migraine independent of the level of health care. We therefore conducted a systematic literature review of five widely used non-pharmacological treatments of migraine, manual joint mobilisation techniques, supervised physical activity, psychological treatment, acupuncture and patient education, and used the results to prepare the present systematic review and meta-analysis.
Methods
This work is structured in accordance with the Population, Intervention, Comparison and Outcome (PICO) framework (16). A systematic review and meta-analysis have been constructed for each PICO reflecting the current evidence (Table 1). The method applied for each PICO follows the Grades of Recommendation, Assessment, Development, and Evaluation (GRADE) (17,18). A protocol for this publication has been registered in Prospero (CRD42020220132).
Identified randomized controlled studies (RCTs) for each PICO question. Studies were found in existing guidelines and systematic reviews, or via a search for individual RCTs.
Organisation of the work
The work was carried out by a joint project – and working group. The project group was responsible for coordinating the work and was comprised of a chairman, a project leader, a search specialist, a lead reviewer and a methodologist. The multidisciplinary working group included members appointed by professional organizations and scientific societies who provided input and guidance throughout the process. A reference group comprising stakeholders within the Danish health care system provided feedback on the PICO questions and the final recommendations. The final product was peer-reviewed by two external reviewers and in a public hearing. Potential conflicts of interests from any of the individuals involved were declared and made publicly available. The individuals involved and their conflicts of interest can be found in the public available guideline published in Magicapp.org.
Clinical questions
PICO questions were formulated to investigate the effect of five specific, widely used non-pharmacological interventions for patients diagnosed with migraine.
This article comprises PICO 1, 3, 5, 7, and 9. PICO 2, 4, 6, 8, and 10 concerning tension-type headache are published elsewhere.
The interventions were defined as follows:
- Manual joint mobilisation techniques (PICO 1):
All manual joint mobilisation techniques aiming to affect joints, muscles and connective tissue in the cervical, thoracic, and lumbar spine. That implies mobilisation or manipulation within the joints’ normal range of motion, i.e. mobilisation as well as manipulation of the spine. The intervention had to be performed by relevant professional staff. The intervention period was 1–12 months.
- Supervised physical activity (PICO 3):
The physical activity program had to be supervised or instructed by relevant professional staff. Minimum intervention period was six weeks.
Exercise was defined according to the WHO-definition: A subcategory of physical activity that is planned, structured, repetitive, and purposeful in the sense that the improvement or maintenance of one or more components of physical fitness is the objective (21).
- Psychological treatment (PICO 5):
The treatment included individual or group-based interventions performed by a professional with knowledge and experience regarding migraine patients. Interventions included various types of therapy basically addressing self-efficacy aiming at secondary prevention and increased quality of life by improving both, the understanding of the disease and the coping strategies. Interventions had to be manualised or standardised.
- Acupuncture (PICO 7):
Intervention using thin, skin penetrating needles including “dry needling” and “trigger-point-acupuncture”. Electro-acupuncture was excluded. The intervention period should consist of minimum six treatment sessions.
- Patient education (PICO 9):
The intervention had to contain disease specific education on individual or class level assuring sufficient knowledge about the disease and its handling. Disease specific education addressed patients and their family members and comprised information about the disease, its treatment, medication overuse, self-care, life-style, physical activity, balanced diet, and sleep. Didactic methods might include exercise, home-exercise, and dialogue. The intervention had to be conducted by a trained professional.
Literature searches and study selection
A systematic search for literature was performed from May 2020 to July 2020 in databases including EMBASE, MEDLINE, PsycINFO, CINAHL and PEDRO. A search for randomized controlled trials (RCTs) was performed by subdividing the search into three major steps: 1) search for RCTs in existing guidelines, 2) search for RCTs in existing systematic reviews and 3) search for individual published RCTs. The search strategy was based on medical subject heading (MeSH and EMTREE) related to our eligibility criteria as well as freetext search words. There were no restrictions regarding publication status, however, the language was limited to English, Danish, Norwegian or Swedish. The search protocol is enclosed as supplement (Supplementary Search Protocol).
To evaluate eligibility, titles and abstracts of identified studies were screened by the lead reviewer and if needed assessed by an additional reviewer. The lead reviewer and a member of the working group then reviewed all full texts. Disagreement was discussed and resolved. The review authors were not blinded to year of publication, journal titles or the authors/institutions. A PRISMA flow chart was constructed to visually document the number of studies identified during the selection process (Supplementary flowcharts literature search).
Data extraction, risk of bias and quality assessment
The data extracted from eligible RCTs included: population demographics, details of the intervention and control conditions, outcome and the time of measurement. Data extraction and risk of bias were performed independently by the lead reviewer and the methodologist. Risk of bias was assessed using the Cochrane risk of bias tool (22). If relevant, clinical guidelines or systematic reviews were identified and the methodological quality was assessed using the AGREE-II tool (23) and the AMSTAR II tool, respectively (24). Only guidelines and systematic reviews of sufficient methodological quality were included. Discrepancies during data extraction and quality assessment were identified and resolved through discussion, which included a third reviewer if needed.
Summary measures
If data across the identified RCTs were comparable, a meta-analysis for each outcome was constructed to give a summary measure of the effect. Data was extracted in the online software program Covidence (Covidence team https://www.covidence.org/home) and exported to RevMan5 (Review Manager (RevMan) (Computer Program) (2014), Version 5.3 In; Copenhagen; The Nordic Cochrane Centre, Cochrane Collaboration) where random-effect models were used to calculate pooled estimates of effects. For dichotomous outcome, a relative risk (RR) and 95% confidence interval were calculated. For continuous outcomes, the mean difference (MD) and the 95% confidence interval were calculated. However, if different measurement scales were applied across the studies, a standardised mean difference (SMD) was used to estimate the effect size. Statistical heterogeneity was quantified using I2 statistic, with an I2> 50% being considered substantial heterogeneity (25). A forest plots was constructed for each outcome. Data was not sufficient to provide any subgroup analyses.
Certainty of evidence
The certainty of evidence for each outcome was evaluated using the GRADE approach (26), which includes four possible ratings: high, moderate, low and very low. If needed, downgrading was performed for each outcome by evaluating the degree of risk of bias, inconsistency, indirectness, imprecision, and publication bias. For each PICO, the overall certainty of evidence was based on the lowest level of evidence obtained of the primary outcomes.
From evidence to recommendation
Recommendations were constructed using the GRADE approach (26). When evidence was available for a given PICO, either a strong or weak recommendation in favor of or against an intervention was made. Final recommendations were based on a combined evaluation of the identified benefits and harms, the certainty of the evidence and the patient preferences.
Patient preferences
Patient preferences were based on the interdisciplinary expert opinion of the working group and the reference group as well as on patient involvement comprising the answers of 380 patients to a questionnaire of the Danish Knowledge Center for Headache, which was distributed via Facebook and patient associations. Patient answers were collected over a period of 2 weeks in June 2020. The questionnaire focused on the patients’ expectations regarding interventions by physiotherapists, chiropractors, psychologists, acupuncture and education (lectures/classes) as well as the likelihood with which patients would ask for a specific intervention again.
Results
Literature search and study selection
An initial search for existing guidelines identified one relevant and methodological well-performed guideline (14) according to the AGREE-II tool. A subsequent search for systematic reviews identified a total of 19 relevant reviews as assessed by the AMSTAR II tool. The AGREE-II and AMSTAR II evaluations can be found in Supplementary Figures 1 and 2. Relevant RCTs were extracted from the identified guideline and systematic reviews. A subsequent search for individual RCTs, lead to further identification of relevant studies for each PICO (PICO 1: n = 1; PICO 3: n = 1; PICO 5: n = 1; PICO 7: n = 1; PICO 9: n = 3). The flowchart for each PICO can be found in the Supplementary flowcharts literature search. The relevant evidence for each PICO is given in Table 1. In addition, an overview over the identified evidence is given (Supplementary overview over the identified relevant studies).
Estimated effects and recommendations
The included RCTs for each PICO and the assessed outcomes can be found in Table 1. The forest plots for each outcome can be found in Supplementary Figure 3. The information concerning the benefits and harms, patient preferences and certainty of the evidence was used in constructing the final recommendations. An overview can be found in Table 2.
Overview of the recommendations for the use of non-pharmacological treatment for patients with migraine.
Patient questionnaire
380 patients answered to the questionnaire of the Danish Knowledge Center for Headache. The patients’ most distinctive expectations regarding the different interventions were improved quality of life, reduced number of headache days and reduced use of analgesics. 86% of the patients expected education to result in increased knowledge about headache and headache treatment. Psychological treatment was expected to result in improved pain coping strategies (63%) and positive impact on depression, anxiety and stress (58%). Regarding the likelihood with which patients would ask for a specific intervention again, there was a certain amount of variability. However, 54% of the patients would ask for education again (Supplementary Figure 4).
Clinical questions
Manual joint mobilisation techniques
Two relevant RCTs were identified (Table 1, Supplementary overview over the identified relevant studies). No change was observed for the two critical outcomes (headache frequency, quality of life) and 3 out of 8 secondary outcomes (headache intensity, number of migraine days and use of analgesics). No evidence was found relating to the remaining secondary outcomes. The overall certainty of evidence was rated as low due to imprecision. Of note, the identified relevant studies did not comprise soft tissue interventions such as trigger point treatment. Thus, our recommendation is restricted on the use of manual therapy techniques. Results showed that no serious adverse events were observed following the use of manual therapy techniques. With regards to patient preferences, it was expected that patients who present with neck pain alongside migraine, would prefer this intervention. Based on these findings, the working group made a weak recommendation for considering the use of manual therapy techniques in addition to standard treatment for patients with migraine (Table 2).
Supervised physical activity
Six relevant RCTs were identified (Table 1, Supplementary overview over the identified relevant studies). Results showed that supervised physical activity might have a positive impact on quality of life when measured at longest follow-up. No change was observed for the remaining identified outcomes. The overall certainty of evidence was rated as very low due to risk of bias, inconsistency and imprecision. No serious adverse events were observed. It was expected that there was a certain amount of variability in the number of patients who would prefer this intervention. Based on these findings, the working group made a weak recommendation for considering the use of supervised physical activity in addition to standard treatment for patients with migraine (Table 2).
Psychological treatment
In this PICO, nine relevant RCTs were identified (Table 1, Supplementary overview over the identified relevant studies). The intervention period was 4 weeks – 4 months. No change was observed for the identified outcomes. No serious adverse events were observed following psychological intervention. The overall certainty of evidence was rated as very low due to risk of bias, inconsistency and imprecision. Furthermore, it was expected that there would be a certain amount of variability in the number of patients who would prefer this intervention. Based on these findings, the working group made a weak recommendation for considering the use of psychological treatment in patients for whom the burden of migraine has a substantial impact on their daily life (Table 2).
Acupuncture
Seven relevant RCTs were identified (Table 1, Supplementary overview over the identified relevant studies). Results showed that the use of acupuncture might have a positive impact on headache frequency, headache intensity, and quality of life at the end of treatment as well as on the general use of attack-medicine/analgesics. There was no difference in the occurrence of serious adverse events between the intervention and control group. No other changes were observed for the remaining identified outcomes. The overall certainty of evidence was low due to risk of bias and inconsistency. It was expected that there would be a certain amount of variability in the number of patients who would prefer this intervention. Based on these findings, the working group made a weak recommendation for considering the use of acupuncture in addition to standard treatment for patients with migraine (Table 2).
Patient education
Five relevant RCTs were identified (Table 1, Supplementary overview over the identified relevant studies). The intervention period was 1 day – 3 months. Results showed that patient education might have a positive impact on self-rated health and quality of life as well as increase the number of patients with improved level of knowledge about their disease and its treatment. No serious adverse events were observed and no other changes were observed for the remaining identified outcomes. The overall certainty of evidence was very low due to risk of bias and imprecision. It was expected that most of the patients would ask for this intervention. Based on these findings, the working group made a weak recommendation for considering the use of patient education in addition to standard treatment for patients with migraine (Table 2).
Discussion
This systematic review and meta-analysis addressed five clinical questions, which could not be answered based on existing clinical guidelines or systematic reviews published after 2012. We collected and assessed all available evidence based on the method described by the Danish Health Authorities for developing national clinical guidelines. Recommendations were based on RCTs. However, the certainty of the available evidence from RCTs was consistently down-graded to low (manual therapy techniques, acupuncture) or very low (supervised physical activity, psychological treatment, patient education) due to imprecision (manual therapy techniques, supervised physical activity, psychological treatment, patient education), inconsistency (supervised physical activity, psychological treatment, acupuncture), and risk of bias (supervised physical activity, psychological treatment, acupuncture, patient education).
Overall, there was a striking lack of evidence for the efficacy of the interventions evaluated. Partially, studies did not differentiate between migraine and tension-type headache or interventions were applied on different types of headache, which were not necessarily defined according to the diagnostic criteria of the International Headache Society (19). Moreover, the evaluation and comparison of the treatment results turned out to be difficult due to the numerous different interventions and control groups used as well as the lack of blinded interventions. Different outcomes, numbers of interventions applied and treatment periods resulted in a lack of evidence and uncertainty about the most effective treatment. Frequently, the study design resulted in a high risk for performance and detection bias, inconsistent and imprecise results. Most of the interventions were neither manualised nor standardised and performed by a variety of professionals.
Thus, recommendations are based on few, mostly small and methodologically weak studies. This lack of high-quality clinical trials in the field of non-pharmacological interventions in migraine treatment constitutes the main weakness, which is reflected in the weak recommendations within this systematic review and meta-analysis. Accordingly, the authors’ final recommendations were not only based on the level of evidence, but also on the lack of serious adverse events, and the patients’ preferences.
However, our results are comparable to the recommendations of other guidelines from (27) and Great Britain (14), but we expect that new high-quality clinical research focusing on non-pharmacological interventions in migraine patients will be likely to affect future guideline recommendations.
The strength of our recommendation is the organization of the work, which was performed, similar to other guidelines (28) as well as the strong adherence to relevant scientific standards, even if the authors were limited in the number of clinical questions, which could be addressed.
However, future research on this issue is desperately needed and should include all types of non-pharmacological treatments, e.g. the increasing variety of interventions, e.g. neuromodulatory approaches. Moreover, interventions should be evaluated using clinical trials according to the guidelines from the International Headache Society (29) as well as the CONSORT statement for reporting randomized trials (http://www.consort-statement.org/).
Conclusion
Based on the level of current evidence, the lack of serious adverse events, and the patients’ preferences, the authors recommend considering manual therapy techniques, supervised physical activity, psychological treatment, acupuncture, and patient education as a supplement to standard treatment.
Key findings
Manual therapy techniques, supervised physical activity, psychological treatment, acupuncture, and patient education should be considered as a supplement to standard treatment in migraine patients. Manual therapy techniques, supervised physical activity, psychological treatment, acupuncture, and patient education were not associated with serious adverse events.
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Supplemental material, sj-pdf-5-cep-10.1177_03331024211034489 for Manual joint mobilisation techniques, supervised physical activity, psychological treatment, acupuncture and patient education in migraine treatment. A systematic review and meta-analysis by Dagmar Beier, Henriette E Callesen, Louise N Carlsen, Kirsten Birkefoss, Hanna Tómasdóttir, Hanne Wűrtzen, Henrik W Christensen, Lotte S Krøll, Mette Jensen, Christel V Høst and Jakob M Hansen in Cephalalgia
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Supplemental material, sj-pdf-6-cep-10.1177_03331024211034489 for Manual joint mobilisation techniques, supervised physical activity, psychological treatment, acupuncture and patient education in migraine treatment. A systematic review and meta-analysis by Dagmar Beier, Henriette E Callesen, Louise N Carlsen, Kirsten Birkefoss, Hanna Tómasdóttir, Hanne Wűrtzen, Henrik W Christensen, Lotte S Krøll, Mette Jensen, Christel V Høst and Jakob M Hansen in Cephalalgia
Footnotes
Acknowledgements
We would like to thank the members of the reference group for their valuable discussions and comments that helped to improve the guideline: Ann Wilhelmsen, Senior Adviser, Regions of Denmark, appointed by the Regions of Denmark. Anne Bülow, appointed by Migraine Denmark. Beate Vesterskov, Psychologist, Headache Clinic, Hospital of South West Jutland, Denmark, appointed by the Regions of Denmark. Bent Ove Larsen, appointed by the Danish Association of People suffering from Headache. Jette Bach, appointed by the Migraine and Headache Association. Lea Heegaard, Chief Adviser, Danish Committee for Health Education, appointed by the Danish Committee for Health Education. Lise Holten, Chief Adviser, Local Government Denmark, appointed by the Local Government Denmark. Sonja Antic, Consultant, Headache Clinic, University Hospital Århus, Denmark, appointed by the Regions of Denmark.
Availability of the data
Declaration of conflicting interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by the Danish Health Authority.
References
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