Page 111 - The clinical aspects and management of chronic migraine Judith Anne Pijpers

Measurements and outcomes
All participants prospectively kept a 4-week diary, with daily registration of headache characteristics, accompanying symptoms and use of acute headache medication, during the baseline assessment period and the post treatment period (weeks 9-12) In addition, questionnaires were filled out at baseline regarding allodynia, depression and anxiety. Allodynia was questioned by the previously used and published Dutch Allodynia Symptom Checklist (ASC) 10, which is analogous to the validated English ASC 11,18. The ASC comprises 12 symptoms of cutaneous allodynia, namely pain or unpleasant sensation on the skin during: i) combing the hair; ii) wearing a pony tail; iii) shaving the face; iv) wearing eyeglasses; v) wearing contact lenses; vi) wearing earrings; vii) wearing a necklace; viii) wearing tight cloths; ix) taking a shower; x) resting the head on a pillow; xi) exposure to heat and xii) exposure to cold. Allodynia was scored as present when at least two of these symptoms occurred 10,11. To distinguish subtypes of allodynia, the 12 items were recoded based on i) spatial distribution and ii) type of stimulus. Based on the spatial distribution of referred hypersensitivity, allodynia was scored as cephalic allodynia (presence of allodynia whilst combing the hair, wearing a pony tail, shaving the face, wearing eyeglasses, wearing contact lenses, wearing earrings, taking a shower, resting the head on a pillow, exposure to heat, or exposure to cold) or extracephalic allodynia (presence of allodynia whilst wearing a necklace or wearing tight cloths). In case of both cephalic and extracephalic allodynia, the complaints were categorised as extracephalic allodynia, as extracephalic (thalamic, third order sensitisation) can be considered as more severe or advanced than cephalic (trigeminal nucleus caudalis, second order sensitisation). Based on previously performed factor analysis 10, the items were recoded based on type of stimulus as thermal (presence of allodynia whilst exposure to heat, exposure to cold or resting the head on a pillow), mechanical (presence of allodynia whilst combing the hair, wearing a pony tail, shaving the face, wearing eyeglasses, wearing contact lenses, wearing earrings, wearing a necklace, wearing tight cloths or taking a shower) or both thermal and mechanical. For the recoding into subtypes, ‘no allodynia’ was defined as absence of any allodynia symptoms. Hence, presence of cephalic, extracephalic, mechanical or thermal was scored as positive if one or more symptoms were reported, and was thus less strict compared with the overall allodynia definition, as the items per subgroup are more limited. Anxiety and depression were scored as present using a cut-off
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Allodynia as predictor for treatment response
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