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Acupuncture for the Prevention of Tension-Type Headache (2016)
Author’s Accepted Manuscript ACUPUNCTURE FOR THE PREVENTION OF TENSION-TYPE HEADACHE (2016) Arya Nielsen
www.elsevier.com/locate/jsch
PII: DOI: Reference:
S1550-8307(17)30055-1 http://dx.doi.org/10.1016/j.explore.2017.03.007 JSCH2190
To appear in: Explore: The Journal of Science and Healing Cite this article as: Arya Nielsen, ACUPUNCTURE FOR THE PREVENTION OF TENSION-TYPE HEADACHE (2016), Explore: The Journal of Science and Healing, http://dx.doi.org/10.1016/j.explore.2017.03.007 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Section Head: Cochrane Reviews
Acupuncture for the prevention of tension-type headache (2016). Update of Cochrane Database Syst Rev. 2009;(1):CD007587.
Arya Nielsen, PhD
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of tension-type headache. Cochrane Database Syst Rev. 2016;48(CD007587 %@ doi: 10.1002/14651858.CD007587.pub2.)
BACKGROUND: Acupuncture is often used for prevention of tension-type headache but its effectiveness is still controversial. This is an update of our Cochrane review originally published in Issue 1, 2009 of The Cochrane Library. OBJECTIVES: To investigate whether acupuncture is a) more effective than no prophylactic treatment/routine care only; b) more effective than 'sham' (placebo) acupuncture; and c) as effective as other interventions in reducing headache frequency in adults with episodic or chronic tension-type headache. SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE and AMED to 19 January 2016. We searched the World Health Organization (WHO) International Clinical Trials Registry Platform to 10 February 2016 for ongoing and unpublished trials. SELECTION CRITERIA: We included randomised trials with a post-randomization observation period of at least eight weeks, which compared the clinical effects of an acupuncture intervention with a control (treatment of acute headaches only or routine care), a sham acupuncture intervention or another prophylactic intervention in adults with episodic or chronic tension-type headache. DATA COLLECTION AND ANALYSIS: Two review authors checked eligibility; extracted information on participants, interventions, methods and results; and assessed study risk of bias and the quality of the acupuncture intervention. The main efficacy outcome measure was response (at least 50% reduction of headache frequency) after completion of treatment (three to
four months after randomization). To assess safety/acceptability we extracted the number of participants dropping out due to adverse effects and the number of participants reporting adverse effects. We assessed the quality of the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation). MAIN RESULTS: Twelve trials (11 included in the previous version and one newly identified) with 2349 participants (median 56, range 10 to 1265) met the inclusion criteria. Acupuncture was compared with routine care or treatment of acute headaches only in two large trials (1265 and 207 participants), but they had quite different baseline headache frequency and management in the control groups. Neither trial was blinded but trial quality was otherwise high (low risk of bias). While effect size estimates of the two trials differed considerably, the proportion of participants experiencing at least 50% reduction of headache frequency was much higher in groups receiving acupuncture than in control groups (moderate quality evidence; trial 1: 302/629 (48%) versus 121/636 (19%); risk ratio (RR) 2.5; 95% confidence interval (CI) 2.1 to 3.0; trial 2: 60/132 (45%) versus 3/75 (4%); RR 11; 95% CI 3.7 to 35). Long-term effects (beyond four months) were not investigated. Acupuncture was compared with sham acupuncture in seven trials of moderate to high quality (low risk of bias); five large studies provided data for one or more meta-analyses. Among participants receiving acupuncture, 205 of 391 (51%) had at least 50% reduction of headache frequency compared to 133 of 312 (43%) in the sham group after treatment (RR 1.3; 95% CI 1.09 to 1.5; four trials; moderate quality evidence). Results six months after randomization were similar. Withdrawals were low: 1 of 420 participants receiving acupuncture dropped out due to adverse effects and 0 of 343 receiving sham (six trials; low quality evidence). Three trials reported the number of participants reporting adverse effects: 29 of 174 (17%) with acupuncture versus 12 of 103 with sham (12%; odds ratio (OR) 1.3; 95% CI 0.60 to 2.7; low quality evidence). Acupuncture was compared with physiotherapy, massage or exercise in four trials of low to moderate quality (high risk of bias); study findings were inadequately reported. No trial found a significant superiority of acupuncture and for some outcomes the results slightly favored the comparison therapy. None of these trials reported the number of participants dropping out due to adverse effects or the number of participants reporting adverse effects. Overall, the quality of the evidence assessed using GRADE was moderate or low, downgraded mainly due to a lack of blinding and variable effect sizes.
AUTHORS' CONCLUSIONS: The available results suggest that acupuncture is effective for treating frequent episodic or chronic tension-type headaches, but further trials - particularly comparing acupuncture with other treatment options – are needed.
Commentary Tension-type headache (TTH) is the most common type of primary headache (the lifetime prevalence in the general population varies between 30% and 78%),1 global prevalence of tension-type headache increased 15.3% from 2005 to 2015.2 The disability attributable to it is larger worldwide than that due to migraine yet migraine is investigated more often than tensiontype headache.3 Patients may suffer from both types of headache. Patients often manage TTH and cTTH with a blend of therapies that might include over the counter pain medication like Tylenol, non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin, ibuprofen, alleve, and or with prescribed antidepressant medication such as amitriptyline (Elavil). Nonpharmacologic approaches are also engaged by headache sufferers such as relaxation techniques, behavioral interventions and physical modalities like exercise, massage, acupuncture, spinal manipulation and physiotherapy.4 Due to the recurring nature of TTH and cTTH, patients understandably seek out novel forms of care that might spare them both pain, side effects and or expense of their current strategy.
This updated Cochrane review of 12 trials with 2349 subjects found that acupuncture is effective in preventing frequent TTH, e.g., with ‘implications for practice’ stated: ‘the available results suggest that acupuncture is effective for treating frequent episodic or chronic tension-type headaches’..5 ] In kind with another 2016 summary of evidence, a role is emerging for acupuncture as part of a treatment plan for patients with migraine, tension-type and chronic headaches.6
Pain is a primary cause for health care seeking including for acupuncture care. In an acupuncture practice, patients may present with recurring headache as a primary complaint, report headaches as a secondary complaint or report a headache at a session for another health problem. Acupuncturists experience patient headaches as responsive to acupuncture therapy, congruent
with the conclusions of this review. Of interest to clinicians is the definition of kinds of headaches included in the Cochrane reviewed trials, how they were treated and the way in which response is assessed compared to sham, for example. Clinicians and referring practitioners want to know the effect of acupuncture in the short and long term and if, or when referral to an acupuncturist is warranted. Is it equal to other options of care or does acupuncture provide an advantage over other options of care?
The acupuncture trials in this review include primarily comparisons of acupuncture needling (minimum six weekly sessions) to usual care or to sham. Acupuncture added to usual care (typically pain killers or nonsteroidal anti-inflammatory medications) was superior to usual care alone. This is congruent with the real world clinical experience of acupuncturists. On the other hand, that acupuncture is interpreted as having only a mild effect over ‘placebo’ would be contested by practitioners because the kinds of sham used in the included trials resemble styles of practice and not inert controls. Practicing acupuncturists are confident that were acupuncture to be compared to truly inert ‘placebo’ controls, the comparative advantages of true acupuncture would be revealed as substantially greater than the estimates seen in this review. Insert Table 1
The confidence in sham acupuncture ‘There is some evidence that sham acupuncture is associated with larger effects than, for example, a placebo pill or other non-pharmacological sham interventions’.7 In individual patient data meta-analysis, acupuncture was significantly superior to all categories of control group.8 For trials that used penetrating needles for sham control, acupuncture had smaller effect sizes than for trials in which acupuncture was compared to non-penetrating sham or sham control without needle. In fact penetrating needles as a control is now discouraged.8 Yet ‘…even the nonpenetrating ‘placebo’ needles might activate unmyelinated (C ‘tactile’) afferent nerves which can influence pain perception and so too cannot be regarded as inert.9
If sham placebo arms are meant to have no or negligible physical effect, but in fact demonstrate a larger than negligible clinical effect, then it follows that many sham acupuncture treatments are not inert controls but rather comparisons of kinds of stimulation, i.e. needle stimulation at points
off channel, or mild or simulated stimulation of points on or off channel. Rather than comparing an active intervention to an inert control, these trials may in fact be finding the effect of variable dosage stimulation. While the authors of this review intentionally excluded trials that compare different forms of acupuncture, that may be precisely what they have done.
It is as if comparing variable dosage of antibiotics, finding a verum dose slightly more effective than a milder dose would not lead to a conclusion of the ineffectiveness of antibiotic therapy. A conclusion that acupuncture is, in fact, effective over sham is important to clinicians and patients weighing options of care. That these findings are interpreted as insubstantial, i.e. only mildly effective over sham, is misleading if the fact that acupuncture ‘sham’ methods are in themselves an active form of treatment is not taken into consideration.10 Acupuncture continues to be devalued by those who believe that it is solely a placebo treatment when in fact from this review what follows is more an insight regarding treatment dosage; the more active acupuncture treatment given at true acupuncture points is more effective than milder forms of penetrating or nonpenetrating point or nonpoint stimulation. A truly inactive sham control for acupuncture has yet to be developed and indeed may not be possible. Further, active or mild acupuncture treatment appears to offer benefit to TTH and cTTH sufferers engaging in usual care. Therefore, clinicians would do well to consider referral for patients for whom usual care is insufficient, where headaches persist with usual care treatment or for whom adverse effects of existing treatment require a new approach.
Finally, how acupuncture treatments compare to other nonpharmacological interventions for TTH cannot be answered at present. How acupuncture compares to medication is undertaken in two places. First, as mentioned above, acupuncture added to usual care (pain meds or NSAIDs) is superior to usual care alone. Only one trial attempted to compare acupuncture directly to pharmacologic treatment for cTTH, that is, with an arm using the antidepressant amitriptyline. However, patients were unwilling to participate in the study due to a possibility of being randomised to amitriptyline, which is associated with unpleasant adverse effects. Or as patients often remark: there is the condition and there is the treatment for the condition. In medicine this is often described as weighing benefits and harms.
Change in review title from 2009 The reviewers state that they changed the title of this review update from ‘Acupuncture for tension-type headache’ (2009) to ‘Acupuncture for the prevention of tension-type headache’ (2016): ‘…to make it more clear that this review does not address the treatment of acute headaches’. While the authors confirm their conclusions remain unchanged from 2009, the change in title situates their conclusions in a way that may be confusing for readers and for referring practitioners. Should they refer a patient who sits in their office with a tension headache and if so can they expect relief or is acupuncture only meant as preventive for the next TTH episode? In fact, there is evidence from this review and other reviews that suggests that acupuncture is effective in treating individual episodes of headache including migraine and TTH6,11, that acupuncture is a beneficial addition to usual care in the treatment of acute headache and headache frequency. Evidence is graded ‘moderate’ that acupuncture has benefit over sham, a finding they agree is on par with reviews on treatment for chronic pain12,13. They report on 2 trials that assessed effect for acute headache in terms of at least 50% reduction in headache frequency, where acupuncture was superior in both. The change in title does not appear to be intended to downgrade evidence in terms of treating a presenting headache but to give weight to the analysis of collective data upon the effects of acupuncture for frequency of tension-type and chronic headaches over the long term. This conclusion is relevant to patients and referring clinicians who may also want to reduce the burden, side-effects and risks of analgesic or nonsteroidal inflammatory medications that are commonly used to manage TTH and cTTH headaches.
Medication: benefits and harms The desire of patients to reduce or avoid medication is a feature of clinical life that could not be comprehensively addressed in the review: the very real adverse effects and risks of pharmacological treatment for TTH or cTTH. Patients seek care for pain and for relief from adverse effects of medications. One reviewed trial measured not only pain reduction but cessation of pain medication, 14 an effect that is consistent with real world patients who report less need for pain medication with reduction in pain and or headache frequency. Overall this effect on reducing medication use could not be confirmed in the review due to insufficient
reporting in the individual trials. But even where adverse events were poorly tracked in trials, few subjects dropped out of studies due to adverse effects of acupuncture.
Limitations of the review The authors refer to theories and concepts of traditional East Asian medicine as not having a basis in science;5,7 and that concepts of acupuncture involving specifically located points on a system of ‘channels’ called meridians are controversial’. 15 Such a statement deserves review from a 2002 article by Kaptchuk when there has been considerable science published on the anatomically distinct nature of meridians or channels as cleavages of connective tissue planes16,17, and the distinctly responsive nature of acupuncture points to needle insertion and rotation18,19, creating a greater mechanical signal transduction within the connective tissue compared to non-acupuncture points.20 . Additionally, fMRI studies indicate not only effect in the brain from treatment of specific acupuncture points21-23 but a difference in effect from kinds of needle perturbation applied, with implications for the treatment of pain. 24
There are further distinguishing features of pain for acupuncturists: persistent or recurring nature of a headache and if pain is ‘fixed’, occupying same or similar area can indicate what is called ‘blood stasis’ that requires treatment additional to acupuncture needling. Neither the Cochrane reviewers nor the researchers in the included trials appear to make this distinction, which is fundamental to acupuncture practice and goes beyond point choices, channel science or even styles of acupuncture. Incorporation of these filters have yet to be evaluated in trials that examine a single feature of practice and not how it may be delivered in real world clinical practice where acupuncture is rarely given alone.
The update of this review from 2009 is relevant to clinicians as the authors clarified their original findings and state that this review has now been ‘stabilized’ and will be re-assessed for updating in ten years. However, they also point to the need for large high quality trials that compare acupuncture to other effective treatments rather than to sham acupuncture. In the event of those kinds of trials being added to the literature, an update might be expected sooner.
AUTHOR BIO Arya Nielsen, PhD works in the Department of Family Medicine, Icahn School of Medicine at Mount Sinai, at Mount Sinai Beth Israel Medical Center
References 1.
The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia : an international journal of headache. 2013;33(9):629-808.
2.
Disease GBD, Injury I, Prevalence C. Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;388(10053):15451602.
3.
Stovner L, Hagen K, Jensen R, et al. The global burden of headache: a documentation of headache prevalence and disability worldwide. Cephalalgia : an international journal of headache. 2007;27(3):193-210.
4.
Sun-Edelstein C, Mauskop A. Complementary and alternative approaches to the treatment of tension-type headache. Current pain and headache reports. 2012;16(6):539-544.
5.
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of tension-type headache. Cochrane Database Syst Rev. 2016;48(CD007587 %@ doi: 10.1002/14651858.CD007587.pub2.).
6.
Coeytaux RR, Befus D. Role of Acupuncture in the Treatment or Prevention of Migraine, Tension-Type Headache, or Chronic Headache Disorders. Headache. 2016;56(7):12381240.
7.
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of episodic migraine. Cochrane Database Syst Rev. 2016;6(CD001218 %@ doi: 10.1002/14651858.CD001218.pub3).
8.
MacPherson H, Vertosick E, Lewith G, et al. Influence of control group on effect size in trials of acupuncture for chronic pain: a secondary analysis of an individual patient data meta-analysis. PLoS One. 2014;9(4):e93739 %@ doi: 93710.91371/journal.pone.0093739.
9.
Lund I, Lundeberg T. Are minimal, superficial or sham acupuncture procedures acceptable as inert placebo controls? Acupuncture in medicine : journal of the British Medical Acupuncture Society. 2006;24(1):13-15.
10.
Glickman-Simon R. Acupuncture May Be Effective for Prevention of Tension-Type Headache, But Magnitude of Improvement May Be Small Compared to Sham. Explore (NY). 2016.
11.
Thomas DA, Maslin B, Legler A, Springer E, Asgerally A, Vadivelu N. Role of Alternative Therapies for Chronic Pain Syndromes. Current pain and headache reports. 2016;20(5):29.
12.
Vickers AJ, Cronin AM, Maschino AC, et al. Acupuncture for Chronic Pain: Individual Patient Data Meta-analysis. Arch Intern Med. 2012:1-10.
13.
MacPherson H, Vickers A, Bland M, et al. Programme Grants for Applied Research. Acupuncture for chronic pain and depression in primary care: a programme of research. Southampton (UK): NIHR Journals Library; 2017
14.
Endres HG, Bowing G, Diener HC, et al. Acupuncture for tension-type headache: a multicentre, sham-controlled, patient-and observer-blinded, randomised trial. The journal of headache and pain. 2007;8(5):306-314.
15.
Kaptchuk TJ. Acupuncture: theory, efficacy, and practice. Ann Intern Med. 2002;136(5):374-383.
16.
Langevin HM, Yandow JA. Relationship of acupuncture points and meridians to connective tissue planes. The Anatomical record. 2002;269(6):257-265.
17.
Langevin HM, Churchill DL, Wu J, et al. Evidence of connective tissue involvement in acupuncture. FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 2002;16(8):872-874.
18.
Langevin HM, Churchill DL, Cipolla MJ. Mechanical signaling through connective tissue: a mechanism for the therapeutic effect of acupuncture. FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 2001;15(12):22752282.
19.
Langevin HM, Bouffard NA, Badger GJ, Churchill DL, Howe AK. Subcutaneous tissue fibroblast cytoskeletal remodeling induced by acupuncture: evidence for a mechanotransduction-based mechanism. Journal of cellular physiology. 2006;207(3):767-774.
20.
Langevin HM, Churchill DL, Fox JR, Badger GJ, Garra BS, Krag MH. Biomechanical response to acupuncture needling in humans. Journal of applied physiology (Bethesda, Md : 1985). 2001;91(6):2471-2478.
21.
Hui KK, Napadow V, Liu J, et al. Monitoring acupuncture effects on human brain by FMRI. Journal of visualized experiments : JoVE. 2010(38).
22.
Napadow V, Dhond R, Park K, et al. Time-variant fMRI activity in the brainstem and higher structures in response to acupuncture. NeuroImage. 2009;47(1):289-301.
23.
Chae Y, Chang DS, Lee SH, et al. Inserting needles into the body: a meta-analysis of brain activity associated with acupuncture needle stimulation. The journal of pain : official journal of the American Pain Society. 2013;14(3):215-222.
24.
Hui KK, Nixon EE, Vangel MG, et al. Characterization of the "deqi" response in acupuncture. BMC Complement Altern Med. 2007;7:33.
Definition Tension- type headache (TTH)
Chronic tension-type headache (cTTH) Migraine headache
Features Episodes of pain, typically bilateral, pressing or tightening, mild to moderate intensity, does not worsen with routine physical activity “
Frequency More than one but fewer than 15 days per month
Medication Analgesic or nonsteroidal anti-inflammatory drugs
15 or more days per month
Antidepressants such as amitriptyline (Elavil)
Recurrent attacks of severe headache; mostly one-sided
Varies
Prophylactic: propranolol, metoprolol, flunarizine, valproic acid and topiramate
www.elsevier.com/locate/jsch
PII: DOI: Reference:
S1550-8307(17)30055-1 http://dx.doi.org/10.1016/j.explore.2017.03.007 JSCH2190
To appear in: Explore: The Journal of Science and Healing Cite this article as: Arya Nielsen, ACUPUNCTURE FOR THE PREVENTION OF TENSION-TYPE HEADACHE (2016), Explore: The Journal of Science and Healing, http://dx.doi.org/10.1016/j.explore.2017.03.007 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
Section Head: Cochrane Reviews
Acupuncture for the prevention of tension-type headache (2016). Update of Cochrane Database Syst Rev. 2009;(1):CD007587.
Arya Nielsen, PhD
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of tension-type headache. Cochrane Database Syst Rev. 2016;48(CD007587 %@ doi: 10.1002/14651858.CD007587.pub2.)
BACKGROUND: Acupuncture is often used for prevention of tension-type headache but its effectiveness is still controversial. This is an update of our Cochrane review originally published in Issue 1, 2009 of The Cochrane Library. OBJECTIVES: To investigate whether acupuncture is a) more effective than no prophylactic treatment/routine care only; b) more effective than 'sham' (placebo) acupuncture; and c) as effective as other interventions in reducing headache frequency in adults with episodic or chronic tension-type headache. SEARCH METHODS: We searched CENTRAL, MEDLINE, EMBASE and AMED to 19 January 2016. We searched the World Health Organization (WHO) International Clinical Trials Registry Platform to 10 February 2016 for ongoing and unpublished trials. SELECTION CRITERIA: We included randomised trials with a post-randomization observation period of at least eight weeks, which compared the clinical effects of an acupuncture intervention with a control (treatment of acute headaches only or routine care), a sham acupuncture intervention or another prophylactic intervention in adults with episodic or chronic tension-type headache. DATA COLLECTION AND ANALYSIS: Two review authors checked eligibility; extracted information on participants, interventions, methods and results; and assessed study risk of bias and the quality of the acupuncture intervention. The main efficacy outcome measure was response (at least 50% reduction of headache frequency) after completion of treatment (three to
four months after randomization). To assess safety/acceptability we extracted the number of participants dropping out due to adverse effects and the number of participants reporting adverse effects. We assessed the quality of the evidence using GRADE (Grading of Recommendations Assessment, Development and Evaluation). MAIN RESULTS: Twelve trials (11 included in the previous version and one newly identified) with 2349 participants (median 56, range 10 to 1265) met the inclusion criteria. Acupuncture was compared with routine care or treatment of acute headaches only in two large trials (1265 and 207 participants), but they had quite different baseline headache frequency and management in the control groups. Neither trial was blinded but trial quality was otherwise high (low risk of bias). While effect size estimates of the two trials differed considerably, the proportion of participants experiencing at least 50% reduction of headache frequency was much higher in groups receiving acupuncture than in control groups (moderate quality evidence; trial 1: 302/629 (48%) versus 121/636 (19%); risk ratio (RR) 2.5; 95% confidence interval (CI) 2.1 to 3.0; trial 2: 60/132 (45%) versus 3/75 (4%); RR 11; 95% CI 3.7 to 35). Long-term effects (beyond four months) were not investigated. Acupuncture was compared with sham acupuncture in seven trials of moderate to high quality (low risk of bias); five large studies provided data for one or more meta-analyses. Among participants receiving acupuncture, 205 of 391 (51%) had at least 50% reduction of headache frequency compared to 133 of 312 (43%) in the sham group after treatment (RR 1.3; 95% CI 1.09 to 1.5; four trials; moderate quality evidence). Results six months after randomization were similar. Withdrawals were low: 1 of 420 participants receiving acupuncture dropped out due to adverse effects and 0 of 343 receiving sham (six trials; low quality evidence). Three trials reported the number of participants reporting adverse effects: 29 of 174 (17%) with acupuncture versus 12 of 103 with sham (12%; odds ratio (OR) 1.3; 95% CI 0.60 to 2.7; low quality evidence). Acupuncture was compared with physiotherapy, massage or exercise in four trials of low to moderate quality (high risk of bias); study findings were inadequately reported. No trial found a significant superiority of acupuncture and for some outcomes the results slightly favored the comparison therapy. None of these trials reported the number of participants dropping out due to adverse effects or the number of participants reporting adverse effects. Overall, the quality of the evidence assessed using GRADE was moderate or low, downgraded mainly due to a lack of blinding and variable effect sizes.
AUTHORS' CONCLUSIONS: The available results suggest that acupuncture is effective for treating frequent episodic or chronic tension-type headaches, but further trials - particularly comparing acupuncture with other treatment options – are needed.
Commentary Tension-type headache (TTH) is the most common type of primary headache (the lifetime prevalence in the general population varies between 30% and 78%),1 global prevalence of tension-type headache increased 15.3% from 2005 to 2015.2 The disability attributable to it is larger worldwide than that due to migraine yet migraine is investigated more often than tensiontype headache.3 Patients may suffer from both types of headache. Patients often manage TTH and cTTH with a blend of therapies that might include over the counter pain medication like Tylenol, non-steroidal anti-inflammatory drugs (NSAIDs) like aspirin, ibuprofen, alleve, and or with prescribed antidepressant medication such as amitriptyline (Elavil). Nonpharmacologic approaches are also engaged by headache sufferers such as relaxation techniques, behavioral interventions and physical modalities like exercise, massage, acupuncture, spinal manipulation and physiotherapy.4 Due to the recurring nature of TTH and cTTH, patients understandably seek out novel forms of care that might spare them both pain, side effects and or expense of their current strategy.
This updated Cochrane review of 12 trials with 2349 subjects found that acupuncture is effective in preventing frequent TTH, e.g., with ‘implications for practice’ stated: ‘the available results suggest that acupuncture is effective for treating frequent episodic or chronic tension-type headaches’..5 ] In kind with another 2016 summary of evidence, a role is emerging for acupuncture as part of a treatment plan for patients with migraine, tension-type and chronic headaches.6
Pain is a primary cause for health care seeking including for acupuncture care. In an acupuncture practice, patients may present with recurring headache as a primary complaint, report headaches as a secondary complaint or report a headache at a session for another health problem. Acupuncturists experience patient headaches as responsive to acupuncture therapy, congruent
with the conclusions of this review. Of interest to clinicians is the definition of kinds of headaches included in the Cochrane reviewed trials, how they were treated and the way in which response is assessed compared to sham, for example. Clinicians and referring practitioners want to know the effect of acupuncture in the short and long term and if, or when referral to an acupuncturist is warranted. Is it equal to other options of care or does acupuncture provide an advantage over other options of care?
The acupuncture trials in this review include primarily comparisons of acupuncture needling (minimum six weekly sessions) to usual care or to sham. Acupuncture added to usual care (typically pain killers or nonsteroidal anti-inflammatory medications) was superior to usual care alone. This is congruent with the real world clinical experience of acupuncturists. On the other hand, that acupuncture is interpreted as having only a mild effect over ‘placebo’ would be contested by practitioners because the kinds of sham used in the included trials resemble styles of practice and not inert controls. Practicing acupuncturists are confident that were acupuncture to be compared to truly inert ‘placebo’ controls, the comparative advantages of true acupuncture would be revealed as substantially greater than the estimates seen in this review. Insert Table 1
The confidence in sham acupuncture ‘There is some evidence that sham acupuncture is associated with larger effects than, for example, a placebo pill or other non-pharmacological sham interventions’.7 In individual patient data meta-analysis, acupuncture was significantly superior to all categories of control group.8 For trials that used penetrating needles for sham control, acupuncture had smaller effect sizes than for trials in which acupuncture was compared to non-penetrating sham or sham control without needle. In fact penetrating needles as a control is now discouraged.8 Yet ‘…even the nonpenetrating ‘placebo’ needles might activate unmyelinated (C ‘tactile’) afferent nerves which can influence pain perception and so too cannot be regarded as inert.9
If sham placebo arms are meant to have no or negligible physical effect, but in fact demonstrate a larger than negligible clinical effect, then it follows that many sham acupuncture treatments are not inert controls but rather comparisons of kinds of stimulation, i.e. needle stimulation at points
off channel, or mild or simulated stimulation of points on or off channel. Rather than comparing an active intervention to an inert control, these trials may in fact be finding the effect of variable dosage stimulation. While the authors of this review intentionally excluded trials that compare different forms of acupuncture, that may be precisely what they have done.
It is as if comparing variable dosage of antibiotics, finding a verum dose slightly more effective than a milder dose would not lead to a conclusion of the ineffectiveness of antibiotic therapy. A conclusion that acupuncture is, in fact, effective over sham is important to clinicians and patients weighing options of care. That these findings are interpreted as insubstantial, i.e. only mildly effective over sham, is misleading if the fact that acupuncture ‘sham’ methods are in themselves an active form of treatment is not taken into consideration.10 Acupuncture continues to be devalued by those who believe that it is solely a placebo treatment when in fact from this review what follows is more an insight regarding treatment dosage; the more active acupuncture treatment given at true acupuncture points is more effective than milder forms of penetrating or nonpenetrating point or nonpoint stimulation. A truly inactive sham control for acupuncture has yet to be developed and indeed may not be possible. Further, active or mild acupuncture treatment appears to offer benefit to TTH and cTTH sufferers engaging in usual care. Therefore, clinicians would do well to consider referral for patients for whom usual care is insufficient, where headaches persist with usual care treatment or for whom adverse effects of existing treatment require a new approach.
Finally, how acupuncture treatments compare to other nonpharmacological interventions for TTH cannot be answered at present. How acupuncture compares to medication is undertaken in two places. First, as mentioned above, acupuncture added to usual care (pain meds or NSAIDs) is superior to usual care alone. Only one trial attempted to compare acupuncture directly to pharmacologic treatment for cTTH, that is, with an arm using the antidepressant amitriptyline. However, patients were unwilling to participate in the study due to a possibility of being randomised to amitriptyline, which is associated with unpleasant adverse effects. Or as patients often remark: there is the condition and there is the treatment for the condition. In medicine this is often described as weighing benefits and harms.
Change in review title from 2009 The reviewers state that they changed the title of this review update from ‘Acupuncture for tension-type headache’ (2009) to ‘Acupuncture for the prevention of tension-type headache’ (2016): ‘…to make it more clear that this review does not address the treatment of acute headaches’. While the authors confirm their conclusions remain unchanged from 2009, the change in title situates their conclusions in a way that may be confusing for readers and for referring practitioners. Should they refer a patient who sits in their office with a tension headache and if so can they expect relief or is acupuncture only meant as preventive for the next TTH episode? In fact, there is evidence from this review and other reviews that suggests that acupuncture is effective in treating individual episodes of headache including migraine and TTH6,11, that acupuncture is a beneficial addition to usual care in the treatment of acute headache and headache frequency. Evidence is graded ‘moderate’ that acupuncture has benefit over sham, a finding they agree is on par with reviews on treatment for chronic pain12,13. They report on 2 trials that assessed effect for acute headache in terms of at least 50% reduction in headache frequency, where acupuncture was superior in both. The change in title does not appear to be intended to downgrade evidence in terms of treating a presenting headache but to give weight to the analysis of collective data upon the effects of acupuncture for frequency of tension-type and chronic headaches over the long term. This conclusion is relevant to patients and referring clinicians who may also want to reduce the burden, side-effects and risks of analgesic or nonsteroidal inflammatory medications that are commonly used to manage TTH and cTTH headaches.
Medication: benefits and harms The desire of patients to reduce or avoid medication is a feature of clinical life that could not be comprehensively addressed in the review: the very real adverse effects and risks of pharmacological treatment for TTH or cTTH. Patients seek care for pain and for relief from adverse effects of medications. One reviewed trial measured not only pain reduction but cessation of pain medication, 14 an effect that is consistent with real world patients who report less need for pain medication with reduction in pain and or headache frequency. Overall this effect on reducing medication use could not be confirmed in the review due to insufficient
reporting in the individual trials. But even where adverse events were poorly tracked in trials, few subjects dropped out of studies due to adverse effects of acupuncture.
Limitations of the review The authors refer to theories and concepts of traditional East Asian medicine as not having a basis in science;5,7 and that concepts of acupuncture involving specifically located points on a system of ‘channels’ called meridians are controversial’. 15 Such a statement deserves review from a 2002 article by Kaptchuk when there has been considerable science published on the anatomically distinct nature of meridians or channels as cleavages of connective tissue planes16,17, and the distinctly responsive nature of acupuncture points to needle insertion and rotation18,19, creating a greater mechanical signal transduction within the connective tissue compared to non-acupuncture points.20 . Additionally, fMRI studies indicate not only effect in the brain from treatment of specific acupuncture points21-23 but a difference in effect from kinds of needle perturbation applied, with implications for the treatment of pain. 24
There are further distinguishing features of pain for acupuncturists: persistent or recurring nature of a headache and if pain is ‘fixed’, occupying same or similar area can indicate what is called ‘blood stasis’ that requires treatment additional to acupuncture needling. Neither the Cochrane reviewers nor the researchers in the included trials appear to make this distinction, which is fundamental to acupuncture practice and goes beyond point choices, channel science or even styles of acupuncture. Incorporation of these filters have yet to be evaluated in trials that examine a single feature of practice and not how it may be delivered in real world clinical practice where acupuncture is rarely given alone.
The update of this review from 2009 is relevant to clinicians as the authors clarified their original findings and state that this review has now been ‘stabilized’ and will be re-assessed for updating in ten years. However, they also point to the need for large high quality trials that compare acupuncture to other effective treatments rather than to sham acupuncture. In the event of those kinds of trials being added to the literature, an update might be expected sooner.
AUTHOR BIO Arya Nielsen, PhD works in the Department of Family Medicine, Icahn School of Medicine at Mount Sinai, at Mount Sinai Beth Israel Medical Center
References 1.
The International Classification of Headache Disorders, 3rd edition (beta version). Cephalalgia : an international journal of headache. 2013;33(9):629-808.
2.
Disease GBD, Injury I, Prevalence C. Global, regional, and national incidence, prevalence, and years lived with disability for 310 diseases and injuries, 1990-2015: a systematic analysis for the Global Burden of Disease Study 2015. Lancet. 2016;388(10053):15451602.
3.
Stovner L, Hagen K, Jensen R, et al. The global burden of headache: a documentation of headache prevalence and disability worldwide. Cephalalgia : an international journal of headache. 2007;27(3):193-210.
4.
Sun-Edelstein C, Mauskop A. Complementary and alternative approaches to the treatment of tension-type headache. Current pain and headache reports. 2012;16(6):539-544.
5.
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of tension-type headache. Cochrane Database Syst Rev. 2016;48(CD007587 %@ doi: 10.1002/14651858.CD007587.pub2.).
6.
Coeytaux RR, Befus D. Role of Acupuncture in the Treatment or Prevention of Migraine, Tension-Type Headache, or Chronic Headache Disorders. Headache. 2016;56(7):12381240.
7.
Linde K, Allais G, Brinkhaus B, et al. Acupuncture for the prevention of episodic migraine. Cochrane Database Syst Rev. 2016;6(CD001218 %@ doi: 10.1002/14651858.CD001218.pub3).
8.
MacPherson H, Vertosick E, Lewith G, et al. Influence of control group on effect size in trials of acupuncture for chronic pain: a secondary analysis of an individual patient data meta-analysis. PLoS One. 2014;9(4):e93739 %@ doi: 93710.91371/journal.pone.0093739.
9.
Lund I, Lundeberg T. Are minimal, superficial or sham acupuncture procedures acceptable as inert placebo controls? Acupuncture in medicine : journal of the British Medical Acupuncture Society. 2006;24(1):13-15.
10.
Glickman-Simon R. Acupuncture May Be Effective for Prevention of Tension-Type Headache, But Magnitude of Improvement May Be Small Compared to Sham. Explore (NY). 2016.
11.
Thomas DA, Maslin B, Legler A, Springer E, Asgerally A, Vadivelu N. Role of Alternative Therapies for Chronic Pain Syndromes. Current pain and headache reports. 2016;20(5):29.
12.
Vickers AJ, Cronin AM, Maschino AC, et al. Acupuncture for Chronic Pain: Individual Patient Data Meta-analysis. Arch Intern Med. 2012:1-10.
13.
MacPherson H, Vickers A, Bland M, et al. Programme Grants for Applied Research. Acupuncture for chronic pain and depression in primary care: a programme of research. Southampton (UK): NIHR Journals Library; 2017
14.
Endres HG, Bowing G, Diener HC, et al. Acupuncture for tension-type headache: a multicentre, sham-controlled, patient-and observer-blinded, randomised trial. The journal of headache and pain. 2007;8(5):306-314.
15.
Kaptchuk TJ. Acupuncture: theory, efficacy, and practice. Ann Intern Med. 2002;136(5):374-383.
16.
Langevin HM, Yandow JA. Relationship of acupuncture points and meridians to connective tissue planes. The Anatomical record. 2002;269(6):257-265.
17.
Langevin HM, Churchill DL, Wu J, et al. Evidence of connective tissue involvement in acupuncture. FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 2002;16(8):872-874.
18.
Langevin HM, Churchill DL, Cipolla MJ. Mechanical signaling through connective tissue: a mechanism for the therapeutic effect of acupuncture. FASEB journal : official publication of the Federation of American Societies for Experimental Biology. 2001;15(12):22752282.
19.
Langevin HM, Bouffard NA, Badger GJ, Churchill DL, Howe AK. Subcutaneous tissue fibroblast cytoskeletal remodeling induced by acupuncture: evidence for a mechanotransduction-based mechanism. Journal of cellular physiology. 2006;207(3):767-774.
20.
Langevin HM, Churchill DL, Fox JR, Badger GJ, Garra BS, Krag MH. Biomechanical response to acupuncture needling in humans. Journal of applied physiology (Bethesda, Md : 1985). 2001;91(6):2471-2478.
21.
Hui KK, Napadow V, Liu J, et al. Monitoring acupuncture effects on human brain by FMRI. Journal of visualized experiments : JoVE. 2010(38).
22.
Napadow V, Dhond R, Park K, et al. Time-variant fMRI activity in the brainstem and higher structures in response to acupuncture. NeuroImage. 2009;47(1):289-301.
23.
Chae Y, Chang DS, Lee SH, et al. Inserting needles into the body: a meta-analysis of brain activity associated with acupuncture needle stimulation. The journal of pain : official journal of the American Pain Society. 2013;14(3):215-222.
24.
Hui KK, Nixon EE, Vangel MG, et al. Characterization of the "deqi" response in acupuncture. BMC Complement Altern Med. 2007;7:33.
Definition Tension- type headache (TTH)
Chronic tension-type headache (cTTH) Migraine headache
Features Episodes of pain, typically bilateral, pressing or tightening, mild to moderate intensity, does not worsen with routine physical activity “
Frequency More than one but fewer than 15 days per month
Medication Analgesic or nonsteroidal anti-inflammatory drugs
15 or more days per month
Antidepressants such as amitriptyline (Elavil)
Recurrent attacks of severe headache; mostly one-sided
Varies
Prophylactic: propranolol, metoprolol, flunarizine, valproic acid and topiramate