Exploring the use of manual therapy as an adjunctive therapy to 'care as usual' on outcomes in chronic migraine.

Abstract

Although chronic migraine (CM) has an estimated of worldwide annual prevalence of between1.4% and 2.2%, with the greatest impact on females, the understanding of its pathophysiology is still largely unknown. This has led to a lack of effective treatments and at the time of this study Onabotulinumtoxin A (Botox) was the only medication licensed specifically for CM. However, whilst there are other treatment options, including psychological and physical therapies, their effectiveness in CM is uncertain. A rationale for the use of MT in CM was developed from a narrative review, with a systematic literature review of peer reviewed publications confirming limited research into the role of MT in the treatment of CM. The aim of this study was therefore to explore the effectiveness of manual therapy (MT) as an adjunctive treatment to 'care as usual' in females with CM, using a pragmatic, randomised controlled trial (RCT) in a tertiary headache clinic. Sixty-four female participants with severe CM were randomised into two groups: 'care as usual' and 'care as usual' with MT. The primary outcome was the between group difference in change scores using the Headache Impact Test (HIT6). Secondary outcomes included Patient Global Impression of Change (PGIC) and responder rates. The primary outcome favoured the use of adjunctive treatment with a significant difference in between-group HIT6 change scores. The MT group also had significantly higher responder rates in the HIT6 and PGIC outcomes. The presence of higher baseline levels of cutaneous allodynia, negative coping and emotional distress indicated a greater benefit from the combined MT/ 'care as usual' intervention than 'care as usual' alone. This was the first MT-CM RCT to take place in a UK tertiary NHS headache clinic and contributed new knowledge in several areas: (1) the first use of PGIC outcomes to be reported in an adjunctive CM study which suggested it provides a broader and potentially more patient centred measure of treatment effectiveness, compared to the HIT6 alone. (2) the potential to use movement between allodynia symptom checklist (ASC) categories as a better indication of reduction in allodynia brought about by MT rather than the normal dichotomous cut off score. (3) the first MT-CM study to examine psychological factors and propose that 'care as usual' treatment may be reinforcing negative coping behaviours and maintaining disability in treatment of CM. This study contributes to a body of knowledge on MT for CM, and concluded that MT plus 'care as usual' produced better outcomes versus 'care as usual' alone in females severely affected by CM.