Trajectories of relative weight and waist circumference among children with and without developmental coordination disorder

Background

Children with developmental coordination disorder have been found to be less likely to participate in physical activities and therefore may be at increased risk of overweight and obesity. We examined the longitudinal course of relative weight and waist circumference among school-aged children with and without possible developmental coordination disorder.

Methods

We received permission from 75 (83%) of 92 schools in southwestern Ontario, Canada, to enrol children in the fourth grade (ages 9 and 10 at baseline). Informed consent from the parents of 2278 (95.8%) of 2378 children in these schools was obtained at baseline. The main outcome measures were body mass index (BMI) and waist circumference. Children were followed up over two years, from the spring of 2005 to the spring of 2007.

Results

Over the course of the study, we identified 111 children (46 boys and 65 girls) who had possible developmental coordination disorder. These children had a higher mean BMI and waist circumference at baseline than did those without the disorder; these differences persisted or increased slightly over time. Children with possible developmental coordination disorder were also at persistently greater risk of overweight (odds ratio [OR] 3.44, 95% confidence interval [CI] 2.34–5.07) and obesity (OR 4.00, 95% CI 2.57–6.21) over the course of the study.

Interpretation

Our findings showed that children with possible developmental coordination disorder were at greater risk of overweight and obesity than children without the disorder. This risk did not diminish over the study period.Developmental coordination disorder is a neuro-developmental condition that affects 5%–6% of school-aged children.¹ Children with the disorder present with a range of coordination difficulties, including fine and gross motor problems,² all of which interfere with normal daily activities, recreational activities and academic performance skills such as handwriting.³ Developmental coordination disorder is diagnosed when existing neurologic and physical problems are ruled out as the cause of motor coordination difficulties and intellectual development has been taken into consideration (Box 1).^1,4 The clinical implications of a diagnosis have been described previously.⁵

Box 1.?Diagnostic criteria for developmental coordination disorder

1. Performance in daily activities that require motor coordination is substantially below that expected given the person’s chronological age and measured intelligence. This may be manifested by marked delays in achieving motor milestones (e.g., walking, crawling, sitting), dropping things, “clumsiness,” poor performance in sports or poor handwriting.
2. The disturbance in criterion A significantly interferes with academic achievement or activities of daily living.
3. The disturbance is not due to a general medical condition (e.g., cerebral palsy, hemiplegia or muscular dystrophy) and does not meet criteria for a pervasive developmental disorder.
4. If mental retardation is present, the motor difficulties are in excess of those usually associated with it.

Reproduced with permission from the Diagnostic and Statistical Manual of Mental Disorders, Text Revision, Fourth Edition.⁴ Copyright © 2000 American Psychiatric Association.Because children with developmental coordination disorder have been found to be less likely to participate in physical activities,⁶ it has been hypothesized that this condition may be a risk factor for obesity.⁷ Only a few studies have examined the association between motor coordination problems and overweight or obesity in children.^7–10 Moreover, the literature in this area is limited in two key respects. First, previous research has relied almost exclusively on body mass index (BMI) as the outcome measure.^8–10 Although important, BMI is not the only indicator of relative weight and has been shown to be weakly correlated with fat mass in young children.^11,12 Waist circumference provides valid estimates of abdominal fat in pediatric populations¹³ and appears to be a stronger predictor of cardiovascular risk among children.^14,15 Second, previous research in this area has been limited to cross-sectional data, with two notable exceptions.^8,9 However, results from these two prospective studies were mixed: one study showed a significant effect of motor coordination on weight,⁸ the other did not.⁹Our objective was to document several measures of adiposity over time in children with and without developmental coordination disorder.