Headache and acute illness in children.

Thirty-seven children with headaches who were seen in a walk-in clinic were matched to 37 headache-free controls. Thirty percent of the headache group and 11% of the headache-free control group had a body temperature above 38 degrees C (p less than 0.05). Nonrhythmic pain was more commonly associated with fever than was rhythmic pain (p less than 0.05). Of 34 headache subjects who completed questionnaires, those with more intense headaches reported a greater number of headache-exacerbating factors (p less than 0.01). Bilateral headaches were more painful than unilateral headaches, and in two thirds of the subjects, the intensity of pain paralleled the course of the underlying illness. A family history of migraine was more common in the headache group as compared to the headache-free control group (p less than 0.05). Headaches associated with acute illnesses may be a precursor to later migraine.