This research evaluated whether the prevalence of gifted children was higher in a sample of children with primary chronic daily headache (CDH) compared to the general population. As a secondary aim, we sought to measure anxiety and depression -risk factors known to influence intellectual performance - accounting for these psychological factors in cognitive assessments of children with CDH. Three cross-sectional studies were conducted at a children's migraine center with two samples of children and adolescents. The first sample consisted of 368 children recruited consecutively over an 11-month period and the second same consisted of 48 children recruited over an 8-month period. Study participants had to be between the ages of 8 and 17 years, consulting for the first time, and received an International Headache Society (ICHD-II) diagnosis of primary headache (study 1) or CDH (sudies 2 e t 3). A psychological assessment was conducted using validated measures that have been standardized with the French population : the WISC-IV (intellectual performance) ,the R-CMAS (anxiety) and the MDI-C (depression). Results from study 3 indicated that the proportion of children with a diagnosis of CDH to have high intellectual potential was significantly greater than that of the general population (10,4 % vs 2,3 %, OR = 5,0). The average intelligence quotient (IQ) in this sample was statistically higher than population norms, even after controlling for the child's sex and parental socioeconomic status. Three out of four cognitive indexes were significantly higher among children with CDH : verbal Comprehension Index (VCI), perceptual Reasoning Index (PRI) and Working memory Index (WMI), with a particularly strong superiority for the index measuring verbal skills (VCI). Only the Processing Speed Index (PSI) in CDH patients was similar to the population norm. School absenteeism was the only variable to be negatively correlated with it. No association was found between IQ and headache severity, duration of headache history, headache diagnosis, sex, age, anxiety, or depression. In addition, we found that children with headache were on average more anxious and depressed than healthy children, with no distinction found between patients with chronic headache and patients with episodic headache. When this comorbidity of anxiety and/or depression was present, it was most often due to anxious or depressive symptoms that were slightly above average rather than symptoms indicating clinical psychopathology. Finally, children with CDH were found more likely to miss school than children with episodic headache. In line with our clinical experience, this research found a significant proportion of children with CDH to have gifted levels of intellectual performance. This relationship was present despite the complexity of the CDH diagnosis along with its common comorbidity with anxious and depressive symptoms.
