Objective: To assess the evolution of idiopathic headache with early onset and to investigate the influence of early somatic disorders, "life events," and psychiatric disorders on the onset and the course of headache. We also studied the possible prognostic role of gender, headache diagnosis at onset, and history of headache in family members on the course of headache. We also investigated the applicability of the ICHD-II criteria to idiopathic headache in preschool children.
Methods: Prospective evaluation of 25 consecutive headache patients referred before the age of 6 years. Headache diagnosis was based on the IHS 1988 criteria, on the ICHD-II criteria, and on "alternative" clinical criteria [eg, duration less than 1 hour in migraine without aura (MWA), less than 30 minutes in tension-type headache (TTH)]. All patients were assessed by a structured interview to detect early developmental disorders (eg, feeding difficulties or sleep disorders) and "life events" (eg, parents' separation and others according to DSM-IV). All patients underwent clinical observations and assessment of psychiatric comorbidity (ICD-10) by means of interviews and the Child Behaviour Check List. All the above-mentioned evaluations were performed at recruitment (T0) and at the end of the follow-up period (T1).
Results: A total of 25 children with headache (12 males; 13 females) were monitored through long-term clinical follow-up (mean duration: 4.2 years; range: 2.8 to 6.6 years). The "definite" diagnosis of migraine without aura or TTH at T0 was possible in only 6/25 (24%) and 9/25 patients (36%) applying the IHS 1988 criteria and the ICHD-II criteria respectively, but in 20/25 (80%) applying the "alternative" clinical criteria. Evaluation of headache at T1 revealed: remission in 16/25 (64%) patients and persistence in 9/25 (36%). At T1, the ICHD-II diagnosis was possible in 100% of the children with headache persistence (1/9 migraine without aura and 8/9 TTH) and these diagnoses were found to be perfectly concordant with those obtained applying the "alternative criteria." Early developmental disorders were present in 11/25 children, with a significantly higher prevalence in children with headache persistence compared to children showing headache remission (78% vs. 25%; P < .05). No significant differences were found between patients with headache persistence and patients with headache remission with regard to gender, history of headache in family members, headache diagnosis at onset, psychiatric comorbidity at T0, and with regard to "life events" at both T0 and T1. Conversely, the children presenting psychiatric disorders at T1 were more frequently affected by headache than those without psychiatric disorders (59% vs. 15%; P < .05).
Conclusions: Our results suggest that the ICHD-II criteria are too restrictive to allow the classification of migraine without aura and TTH in preschool children. Nevertheless, a diagnosis based on these criteria was possible in all the patients with headache persistence at the end of several years' follow-up. We found a significant association between early somatic disorders and persistence of headache and also between the presence of psychiatric disorders at the end of follow-up and the persistence of headache. "Life events," on the other hand, while not showing a statistically significant association with the evolution of the headache, may nevertheless influence the course of the headache in some patients. Our results suggest that environmental and psychological factors play an important role in idiopathic headache with onset in preschool age, and thus that the diagnostic-therapeutic approach must take these factors into account.