Migrainous visual accompaniments are not rare in late life: the Framingham Study

Questionnaires to elicit symptoms of transient ischemic attacks (TIAs) may detect late-life transient visual symptoms similar to the visual aura of migraine, often without headache. We determined the frequency, characteristics, and stroke outcome of these symptoms in the Framingham Study.

During 1971-1989, at biennial examinations, 2110 subjects of the Framingham cohort were systematically queried about the occurrence of sudden visual symptoms.

Visual migrainous symptoms were reported by 1.23% (26/2110) of subjects (1.33% of women and 1.08% of men). In 65% of subjects the episodes were stereotyped, and they began after age 50 years in 77%. Mean +/- SD age at onset of the episodes was 56.2+/-18.7 years. In 58% of subjects the episodes were never accompanied by headaches, and 42% had no headache history. The number of episodes ranged from 1 to 500 and was 10 or more in 69% of subjects. The episodes lasted 15 to 60 minutes in 50% of subjects. Sixty-five percent of the subjects were examined by a study neurologist, and only 19% of them met the criteria of the International Headache Society. Twelve percent of subjects sustained a stroke after the onset of migrainous visual symptoms: a subarachnoid hemorrhage 1 year later, an atherothrombotic brain stem infarct 3 years later, and a cardioembolic stroke 27 years later. In contrast, of 87 subjects with TIAs in the same cohort, 33% developed a stroke (P = 0.030), two thirds within 6 months of TIA onset.

Late-life-onset transient visual phenomena similar to the visual aura of migraine are not rare and often occur in the absence of headache. These symptoms appear not to be associated with an increased risk of stroke, and invasive diagnostic procedures or therapeutic measures are generally not indicated.