Self-reported headache frequency in Canadian adolescents: validation and follow-up.

OBJECTIVE: To validate our previous estimates of the prevalence of frequent headache and associated factors in a new sample of 12- to 13-year-old adolescent Canadians, and to explore if estimates of the prevalence of frequent headache and associated factors remain stable within the original cohort after a two-year interval. METHODS: We analyzed the self-administered questionnaire microdata files of the National Longitudinal Survey of Children and Youth (NLSCY: 1998-1999). 1694 respondents representing 724,400 youth aged 12 to 13 years were used to validate the prevalence in our initial estimates. From the initial cohort, 1764 respondents representing 819,600 youth, now aged 14 to 15 years, were used to examine whether frequent headache prevalence or associated factors had changed in the intervening two years. RESULTS: Among the analyzed individuals, 26.3% of 12- to 13-year olds and 31.2% of 14- to 15-year olds reported frequent headaches of "about once a week" or more often (P= .001). Our previous study of the NLSCY: 1996-1997 found a prevalence of 26.6% in 12- to 13-year olds. We previously identified 22 risk factors, of which 15 were replicated and one proxy was available within this iteration of the survey. For the 12- to 13-year olds, 14/16 were associated (P < .01, chi-square) with frequent headaches. For the initial cohort, now 14- to 15-year olds, 15/16 risk factors remained associated (P < .01, chi-square) with an increased risk of headaches. CONCLUSIONS: Our estimates of frequent headache prevalence are reliable and consistent in two large nationally representative cohorts of 12- to 13-year olds. In the first of these groups there was an increase in prevalence over 2 years as adolescence progresses. Our identified risk factors for frequent headaches have been validated within another cohort and are maintained as the cohort ages.

Prevalence of reported migraine headaches in Canadian adolescents.

OBJECTIVE: To examine self-reported prevalence data for migraine among adolescent Canadians and to explore how reported migraine treatment varies by age. METHODS: We analyzed the microdata files of the Canadian National Population Health Survey (1996-1997). Respondents reported whether they had "migraine headaches diagnosed by a health professional". They also reported whether they received "any treatment or medication for migraine headaches", with treatments subdivided into drug, diet or "other". RESULTS: 99.9% of 173,216 eligible respondents reported whether they had migraine headaches. Migraine was reported by 2.4% of Canadian youth aged 12-14 years and by 5.0% of 15-19 year-olds compared to 7.2% of adults aged > or = 20 years of age (p< 0.0001, chi-square). Active treatment was used by 51.0% - higher by females (53.1%) than males (44.7%) (p<0.0001 chi-square). Treatment was used by 45.1% of 12-14 year-olds, by 45.7% of 15-19 year-olds and by 51.5% of those > or = 20 years (p=0.0027). The nature of the active treatment choice (drug, diet or other) did not significantly vary within the age groups studied. CONCLUSIONS: We present robust estimates of self-report diagnosed migraine prevalence, derived from a large nationally representative population survey. Estimates of the prevalence of active treatment for migraine provide insight into the burden of migraine within this population.

Self-reported headache frequency and features associated with frequent headaches in Canadian young adolescents.

OBJECTIVE: To explore the associated factors for frequent headache among young adolescent Canadians. METHODS: We analyzed the self-administered questionnaire microdata files of the National Longitudinal Survey of Children and Youth (NLSCY: 1996 to 1997). Two thousand and ninety respondents representing 793,100 Canadian youth aged 12 to 13 years were asked how often they had headaches in the previous 6 months. RESULTS: Of the 2090 adolescents, 1998 (96%) responded. Frequent headaches of "about once a week" or more often were reported by 26.6% of them aged 12 to 13 years (95% CI: 24.2, 28.6). Frequent headaches appear to be associated with a plethora of risk factors germane to the life experience of these young adolescents. All factors were significant at P <.0001 by chi-square analysis and can be loosely categorized as school-related, lifestyle-related, or involving mental health. A multivariate Classification and Regression Tree (CART) analysis models frequent headaches on a depression scale, a self-esteem scale, and ever having smoked, with 60% sensitivity, and 65% specificity. CONCLUSIONS: The NLSCY reveals a remarkable insight into headache frequency and the life experience of Canada's young adolescents with frequent headaches.

Botulinum toxin A as a treatment for excessive drooling in children.

Drooling is problematic for some neurologically impaired children. Botulinum toxin A injection to salivary glands has effectively reduced drooling in adults but has only recently been used to treat children. This was a preliminary study to determine the efficacy and safety of botulinum toxin in children. Children identified as having severe daily drooling were enrolled. The preinjection assessment included measurement of the amount and frequency of drool. Each parotid gland was injected with 5 U of botulinum toxin A. Follow-up was for a minimum of 16 weeks. Nine children were enrolled, 4-17 years of age. All children had moderate or severe mental retardation. At week 4, all patients had a reduced drooling frequency and eight of nine patients had a reduction in the weight of saliva. Overall, five of nine parents (55%) deemed the treatment successful. This preliminary study demonstrates that botulinum toxin A is a relatively effective treatment for some children with significant drooling without serious side effects.

Irritability in Krabbe's disease: dramatic response to low-dose morphine.

Krabbe's disease is characterized by normal neonatal development with subsequent regression and profound, medically intractable irritability. Two female infants presented at 5 months of age with increasing irritability, abnormal motor control, and developmental regression. Investigations confirmed the diagnosis of Krabbe's disease. Maximal treatment of gastroesophageal reflux and nitrazepam 0.1 mg/kg by mouth three times daily were unsuccessful in controlling irritability. Morphine was initiated and titrated to 0.06 mg/kg by mouth every 6 hours in Patient 1 and 0.1 mg/kg by mouth every 8 hours in Patient 2, resulting in remarkably successful control of irritability. The diagnosis of Krabbe's disease is devastating for families and is compounded by the marked irritability. Management is difficult, but in these two infants, irritability was successfully controlled with low-dose morphine.

The epidemiology of infantile spasms.

OBJECTIVE: The aim of this study was to estimate population based incidence rates for infantile spasms (IS) and to study our clinical impression that the incidence of IS has recently decreased in the Canadian Provinces of Nova Scotia and Prince Edward Island. METHODS: Birth cohorts from 1978 to 1998, identified through the hospital health records, EEG records and physician computerized databases, were followed for two years for the development of IS. Disease incidence rates were calculated using denominators derived from Statistics Canada's reported annual live birth rates. RESULTS: The inclusion criteria for IS were fulfilled by 75 patients. The overall incidence of IS was 30.7/100,000 live births (95% Cl 24.3, 38.8). Etiologic classification was symptomatic for 51 cases (68%), cryptogenic for 18 (24%), and idiopathic in six children (8%). Although there were more males (N=44) than females (N=31), the incidence rates were similar. There was a marked variability in annual and five-year incidence rates. CONCLUSIONS: Although the clinical characteristics of our patients were similar to other reported IS populations, the instability in IS incidence rates indicates a need for caution in interpreting smaller IS epidemiologic studies.

Parent perceptions of the value of Pediatric Neurology Clinic visits.

BACKGROUND: There is little data available on the acceptability to parents, of alternate methods of delivering care to their children. This pilot study explored parents' perceptions of conventional clinic visits and their attitudes to potential alternative methods of delivering care. METHODS: Questionnaires were completed by the families of 200 consecutive children before and after a visit to a tertiary-care Pediatric Neurology Clinic in Nova Scotia, Canada. RESULTS: Responses were received from 172 (86%) for the first questionnaire and 138 (69%) for the second. There were 59 new referrals, 76 follow-up visits and 39 were seen because of new concerns. Visiting the clinic resulted in school absenteeism for 85% of the children and lost pay for 19% of the parents. Telephone, video conference or replacement of the physician by a nurse practitioner were acceptable alternate methods of assessment for only 10%. The only factor which was associated with willingness to accept telephone as an assessment modality was an initial opinion that the visit was unnecessary. CONCLUSION: Escalating health care costs and limited specialist availability demand consideration of alternate methods of care delivery. Although adults seem comfortable with care outside the usual clinic setting, there is little data for the pediatric setting. The responses from the parents attending our clinic, indicate that families were happy with services offered in the conventional clinic. In contrast, only 10% found potential alternate methods acceptable. These opinions must be considered in the design of new methods of caring for children.

Validation of a model of gross motor function for children with cerebral palsy.

BACKGROUND AND PURPOSE: Development of gross motor function in children with cerebral palsy (CP) has not been documented. The purposes of this study were to examine a model of gross motor function in children with CP and to apply the model to construct gross motor function curves for each of the 5 levels of the Gross Motor Function Classification System (GMFCS). SUBJECTS: A stratified sample of 586 children with CP, 1 to 12 years of age, who reside in Ontario, Canada, and are known to rehabilitation centers participated. METHODS: Subjects were classified using the GMFCS, and gross motor function was measured with the Gross Motor Function Measure (GMFM). Four models were examined to construct curves that described the nonlinear relationship between age and gross motor function. RESULTS: The model in which both the limit parameter (maximum GMFM score) and the rate parameter (rate at which the maximum GMFM score is approached) vary for each GMFCS level explained 83% of the variation in GMFM scores. The predicted maximum GMFM scores differed among the 5 curves (level I=96.8, level II=89.3, level III=61.3, level IV=36.1, and level V=12.9). The rate at which children at level II approached their maximum GMFM score was slower than the rates for levels I and III. The correlation between GMFCS levels and GMFM scores was (.91. Logistic regression, used to estimate the probability that children with CP are able to achieve gross motor milestones based on their GMFM total scores, suggests that distinctions between GMFCS levels are clinically meaningful. CONCLUSION AND DISCUSSION: Classification of children with CP based on functional abilities and limitations is predictive of gross motor function, whereas age alone is a poor predictor. Evaluation of gross motor function of children with CP by comparison with children of the same age and GMFCS level has implications for decision making and interpretation of intervention outcomes.