Although women with migraine with and without aura are at increased risk for stroke, the absolute risk is still very low. For example, one review reported that the incidence of ischemic stroke per 100,000 person-years among women 20 to 44 years of age was 2.5 for those without migraine not taking estrogen-containing contraceptives, 5.9 for those with migraine with aura not taking estrogen-containing contraceptives, and 14.5 among those with migraine with aura and taking estrogen-containing contraceptives.6 Another important observation is that the incidence of thrombotic stroke dramatically increases from adolescence (3.4 per 100,000 person-years) to 45-49 years of age (64.4 per 100,000 person-years).7 Therefore, older women with migraine are at greater risk for stroke than adolescents.
Diagnostic criteria for migraine with and without aura
In contraceptive counseling, if an estrogen-containing contraceptive is being considered, it is important to identify women with migraine headache, determine migraine subtype, assess the frequency of migraines and identify other cardiovascular risk factors, such as hypertension and cigarette smoking. The International Headache Society has evolved the diagnostic criteria for migraine with and without aura, and now endorses the criteria published in the 3rd edition of the International Classification of Headache Disorders (ICHD-3; TABLES 1 and 2).8 For non-neurologists, these criteria may be difficult to remember and impractical to utilize in daily contraceptive counseling. Two simplified tools, the ID Migraine Questionnaire9 and the Visual Aura Rating Scale (TABLE 3)4 may help identify women who have migraine headaches and assess for the presence of aura.
The ID Migraine Questionnaire
In a study of 563 people seeking primary care who had headaches in the past 3 months, 3 questions were identified as being helpful in identifying women with migraine. This 3-question screening tool had reasonable sensitivity (81%), specificity (75%), and positive predictive value (93%) compared with expert diagnosis using the ICHD-3.9 The 3 questions in this screening tool, which are answered “Yes” or “No,” are:
During the last 3 months did you have the following symptoms with your headaches:
- Feel nauseated or sick to your stomach?
- Light bothered you?
- Your headaches limited your ability to work, study or do what you needed to do for at least 1 day?
If two questions are answered “Yes” the patient may have migraine headaches.
Visual Aura Rating Scale for the diagnosis of migraine with aura
More than 90% of women with migraine with aura have visual auras, leaving only a minority with non–visual aura, such as tingling or numbness in a limb, speech or language problems, or muscle weakness. Hence for non-neurologists, it is reasonable to focus on the accurate diagnosis of visual aura to identify those with migraine with aura.
In the clinical context of contraceptive counseling, the Visual Aura Rating Scale (VARS) is especially useful because it has good sensitivity and specificity, and it is easy to use in practice (TABLE 3).4 VARS assesses for 5 characteristics of a visual aura, and each characteristic is associated with a weighted risk score. The 5 symptoms assessed include:
- duration of visual symptom between 5 and 60 minutes (3 points)
- visual symptom develops gradually over 5 minutes (2 points)
- scotoma (2 points)
- zig-zag line (2 points)
- unilateral (1 point).
Continue to: Of note, visual aura is usually...