Factors of early life as predictors of headache in children at school entry.

To study the main predictors of childhood preschool headache, 1443 families expecting their first child were followed from the onset of pregnancy to the child's sixth year of life. Subject selection was based on stratified randomized cluster sampling. Of the children, 14.9% (144) suffered from headache disturbing daily activities at the age of 6 years. The mother's assessment of the infant's poor health (OR 2.5, 95% CI 1.1 to 5.8) and feeding problems (OR 1.9, 95% CI 1.1 to 3.2) at the age of 9 months predicted later occurrence of headache. At 3 years, depression and sleeping difficulties (according to Achenbach's psychological test) and recurrent difficulties in falling asleep (OR 3.2, 95% CI 1.5 to 7.2) were strong predictors. Headache in other family members (OR 3.5, 95% CI 2.0 to 5.9), especially in the mother (OR 1.7, 95% CI 1.2 to 2.4), predicted preschool headache in a child. At the age of 5 years, travel sickness (OR 2.8, 95% CI 1.5 to 5.1), nocturnal enuresis (OR 1.8, 95% CI 1.1 to 3.0), and the presence of long-term disease (OR 1.8, 95% CI 1.1 to 3.0) were strong predictors of later headache. At the same age, concentration difficulties (OR 2.3, 95% CI 1.3 to 4.2), behavioral problems (OR 2.7, 95% CI 1.1 to 6.4), unusual tiredness (OR 3.8, 95% CI 1.0 to 13.5), and, conversely, high sociability (OR 1.5, 95% CI 1.0 to 2.2) predicted headache. The three last-mentioned psychological factors seemed to be associated with concentration difficulties at the age of 5, which was found to be the strongest predictor. The parents of child headache sufferers often became aware of the child's problems long before the emergence of headache.