Genetic and environmental influences on recurrent headaches in eight to nine-year-old twins.

The major objective of the present study was to estimate genetic and environmental influences on recurrent headaches in prepubescent twins. A nationwide cohort of 8 to 9-year-old Swedish twins (n = 1,480) was screened for nonsymptomatic and recurrent headaches through a questionnaire mailed to their parents (75% response frequency). Among positives, 79% of headaches were classified as migraine or tension-type headache in close accordance with the International Headache Society criteria. The prevalences of migraine and nonmigrainous headaches were 2.4% and 11.3%, respectively, and without significant differences between the sexes or zygosity types. Inheritance on liability to recurrent headaches was estimated to 70% (a2 = 0.70, 95% CI = 0.54-0.82) for boys and girls but the genetic effect was found to be uncorrelated between the sexes. We conclude that genetic and individual specific effects are important for recurrent headaches of migrainous and nonmigrainous types in prepubescent children, and that different genetic etiologies might exist for boys and girls.

A 40-year follow-up of school children with migraine.

A prevalence study of 9000 Swedish school children conducted in 1955 showed that nearly 4% had migraine. The prevalence of migraine was 1.4% at 7 years of age and 5.3% at 15 years of age. From the age of 11 there was a gradual increase of migraine headache and a predominance among girls. A subgroup of 73 children with pronounced migraine and an average onset of 6 years was followed during a period of 40 years. The results showed that 23% of the children were migraine-free before the age of 25, boys significantly more often than girls. However, around the age of 50, more than half of the migraine group still had migraine attacks. A recall bias was found in that a number of the subjects in their middle-life (41%) could not remember that they had had aura symptoms previously. Of those who had become parents, 52% have in their present or previous families had one child or more who had developed recurrent headache, probably of the migraine-type.

Genetic influence in headaches: a Swedish twin study.

The heritability of liability to self-reported migraine and nonmigrainous headaches was examined in two large cohorts from the Swedish Twin Registry consisting of 6448 (the older cohort) and 12,884 (the younger cohort) like-sexed twin pairs. Higher concordance rates were consistently found for lifetime migraine among the monozygotic twins than in the dizygotic twins, as well as for migraine headaches of the recurrent disabling type. In addition, a higher concordance rate was found among the monozygotic twins than in dizygotic twins in a "mixed" group of possible tension-type or mild migraine headaches (or both). The results of structural equation model-fitting analyses showed that genetic effects for migraine headaches were stronger for the females (estimates ranging from 49% to 58%) than for the males (39% to 44%) in the two cohorts. Unique nonshared environmental effects were greatest for the "mixed" group in both sexes (estimates ranging from 60% to 69%). The results are discussed in view of similar large-scale twin studies examining the heritability of liability to migraine.

Computed tomography of the brain in children with minor neurodevelopmental disorders.

Eighty-nine boys and twenty girls with minor neurodevelopmental disorders underwent cranial computed tomography (CT). Twenty-five per cent showed aberrations at CT. The incidence of manifest lefthandedness and of developmental language disorders was not higher among children with pathological CT findings than among those with normal ones. Nineteen per cent of the children with pathological CT results but only 1% of those with normal CT findings had had afebrile seizures. Abnormal chromatographic patterns of peptides and protein associated peptide complexes in the urine were found significantly more often in children with pathological than in those with normal CT.

Familial minor neurodevelopmental disorders.

Sixteen patients (13 males and 3 females) with minor neurodevelopmental disorders from 7 families were examined in an etiologic study. In four of the families (3, 5, 6 and 7) no brain damaging factors could be traced in the prenatal, perinatal or postnatal periods, and genetic main etiologies were strongly suspected. In one family (1) alcohol abuse during the pregnancies was thought to be an etiologically contributing factor. Potentially brain damaging factors were demonstrated in at least one patient from each of the remaining two families (2 and 4), and might, in these cases, have interacted with hereditary factors.

Early bladder training in patients with spina bifida.

A bladder training programme was applied in 43 children with myelomeningocele and complete urinary incontinence. In one group the training was commenced before the age of 3 years (mean age 1.3 years) and in another group between the ages of 3 and 13 years (mean age 5.8 years). The results as regards continence were better in the group with an early start of training, girls showing significantly better results than boys. Pharmacotherapy and cautious urethral surgery were valuable complements in selected cases. Vesico-ureteral reflux disappeared during treatment in 60% of the patients. Patients not showing significant improvement should be candidates for clean intermittent catheterization and/or cholinergic drugs, if detrusor hyperactivity is present.

Dyskinetic cerebral palsy. I. Clinical categories, associated neurological abnormalities and incidences.

An unselected series of 116 dyskinetic cerebral palsy cases born 1959-70 was delineated and subgrouped according to neurological criteria into 35 hyperkinetic (30%) and 81 dystonic (70%) cases. Of the hyperkinetics, 80% had a mild motor disability, while 90% of the dystonics had moderate or severe disability. Subordinated spastic signs were found in 9% of the hyperkinetic and in 44% of the dystonic cases. IQ was greater than 90 in 69% of the hyperkinetics and 25% of the dystonics and less than 50 in 11% and 41%, respectively. Two or more additional neurological abnormalities (spasticity, mental retardation, epilepsy, anarthria, dysarthria, hearing deficit) were detected in 46% hyperkinetic and 81% dystonic cases. A heavy multihandicap complex was present predominantly in the dystonic subgroup. The 5-19 year mortality rate was 6% and was confined to the most severely handicapped dystonic cases. The twin rate was 5%. A total of 9% had birth weights less than or equal to 1500 g, and 31% had less than or equal to 2500 g. The weight- and age-specific incidences increased rapidly with decreasing birth weights and gestational ages. The crude incidence of hyperkinetic cerebral palsy was 0.07 and dystonic cerebral palsy 0.17 per thousand live births.

Migraine in childhood and its prognosis.

In 1955 a population study in Uppsala comprising about 9,000 school children showed that migraine increased from 1.4% at the age of seven to 5.3% at fifteen. With increasing age there was an increasing predominance of girls. A matched comparison between 73 children with more pronounced migraine and 73 control children showed a greater tendency in the migraine group to abdominal pain, motion sickness, sleep disturbance and orthostatic symptoms. In a longitudinal study lasting 23 years the 73 migraine children were followed-up until all were over 30 years of age. During puberty and as young adults 62% were free from migraine for at least two years. Of these, 22% again suffered migraine regularly. Thus, 60% had migraine attacks at 30. Girls seem to have a greater relapse rate than boys. Most of the girls with classical migraine were headache free during pregnancy. Every third family with one parent belonging to the migraine group and with children over four years of age had one child with migraine symptoms. Migraine seems to be more frequently inherited via the mother, and to girls.

Computed tomography of the brain in children with minimal brain damage: a preliminary study of 46 children.

Forty-six children aged 4 to 15 years with minimal brain damage (MBD) underwent computed cranial tomography (CT). The criteria used for a diagnosis of MDB was the presence of clinical features of a developmental disturbance of the central nervous system causing incoordination. CT revealed abnormalities in 15 cases (32.6%), consisting in cerebral atrophy, asymmetry or an anomaly.