title: Botulinum toxin A for prophylactic treatment of migraine and tension headaches in adults: a meta-analysis.
abstract: BACKGROUND
  Botulinum toxin A is US Food and Drug Administration approved for prophylactic treatment for chronic migraines.
  
  
  OBJECTIVE
  To assess botulinum toxin A for the prophylactic treatment of headaches in adults.
  
  
  METHODS
  A search of MEDLINE, EMBASE, bibliographies of published systematic reviews, and the Cochrane trial registries between 1966 and March 15, 2012. Inclusion and exclusion criteria of each study were reviewed. Headaches were categorized as episodic (<15 headaches per month) or chronic (≥15 headaches per month) migraine and episodic or chronic daily or tension headaches.
  
  
  METHODS
  Randomized controlled trials comparing botulinum toxin A with placebo or other interventions for headaches among adults.
  
  
  METHODS
  Data were abstracted and quality assessed independently by 2 reviewers. Outcomes were pooled using a random-effects model.
  
  
  RESULTS
  Pooled analyses suggested that botulinum toxin A was associated with fewer headaches per month among patients with chronic daily headaches (1115 patients, -2.06 headaches per month; 95% CI, -3.56 to -0.56; 3 studies) and among patients with chronic migraine headaches (n = 1508, -2.30 headaches per month; 95% CI, -3.66 to -0.94; 5 studies). There was no significant association between use of botulinum toxin A and reduction in the number of episodic migraine (n = 1838, 0.05 headaches per month; 95% CI, -0.26 to 0.36; 9 studies) or chronic tension-type headaches (n = 675, -1.43 headaches per month; 95% CI, -3.13 to 0.27; 7 studies). In single trials, botulinum toxin A was not associated with fewer migraine headaches per month vs valproate (standardized mean difference [SMD], -0.20; 95% CI, -0.91 to 0.31), topiramate (SMD, 0.20; 95% CI, -0.36 to 0.76), or amitriptyline (SMD, 0.29; 95% CI, -0.17 to 0.76). Botulinum toxin A was associated with fewer chronic tension-type headaches per month vs methylprednisolone injections (SMD, -2.5; 95% CI, -3.5 to -1.5). Compared with placebo, botulinum toxin A was associated with a greater frequency of blepharoptosis, skin tightness, paresthesias, neck stiffness, muscle weakness, and neck pain.
  
  
  CONCLUSIONS
  Botulinum toxin A compared with placebo was associated with a small to modest benefit for chronic daily headaches and chronic migraines but was not associated with fewer episodic migraine or chronic tension-type headaches per month.
authors.affiliation: Department of General Internal Medicine, Zablocki Veterans Affairs Medical Center, and Medical College of Wisconsin, Milwaukee, WI 53295, USA. jjackson@mcw.edu
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Jackson
authors.forename: Akira
authors.initials: A
authors.lastname: Kuriyama
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Hayashino
mesh_terms: D019274:Botulinum Toxins, Type A / Q000009:adverse effects / Q000627:therapeutic use*; D002908:Chronic Disease; D006801:Humans; D008881:Migraine Disorders / Q000517:prevention & control*; D009465:Neuromuscular Agents / Q000009:adverse effects / Q000627:therapeutic use*; D016032:Randomized Controlled Trials as Topic; D018781:Tension-Type Headache / Q000517:prevention & control*; D016896:Treatment Outcome
chemical_list: D009465:Neuromuscular Agents; D019274:Botulinum Toxins, Type A