Psychological distress in children with developmental coordination disorder and attention-deficit hyperactivity disorder

This study explored whether or not a population-based sample of children with developmental coordination disorder (DCD), with and without comorbid attention deficit/hyperactivity disorder (ADHD), experienced higher levels of psychological distress than their peers. A two-stage procedure was used to identify 244 children: 68 with DCD only, 54 with ADHD only, 31 with comorbid DCD and ADHD, and 91 randomly selected typically developing (TD) children. Symptoms of depression and anxiety were measured by child and parent report. Child sex and caregiver ethnicity differed across groups, with a higher ratio of boys to girls in the ADHD only group and a slightly higher proportion of non-Caucasian caregivers in the TD group. After controlling for age, sex, and caregiver ethnicity, there was significant variation across groups in both anxiety (by parent report, F(3,235) = 8.9, p < 0.001; by child report, F(3,236) = 5.6, p = 0.001) and depression (parent report, F(3,236) = 23.7, p < 0.001; child report, F(3,238) = 9.9, p < 0.001). In general, children in all three disorder groups had significantly higher levels of symptoms than TD children, but most pairwise differences among those three groups were not significant. The one exception was the higher level of depressive symptoms noted by parent report in the ADHD/DCD group. In conclusion, children identified on the basis of motor coordination problems through a population-based screen showed significantly more symptoms of depression and anxiety than typically developing children. Children who have both DCD and ADHD are particularly at heightened risk of psychological distress.     

Health-related physical fitness children with severe and moderate developmental coordination disorder

The present study aims to examine physical fitness among children with developmental coordination disorder (DCD) with varying degrees of severity (moderate and severe – mDCD, sDCD), and a group of children without DCD (wDCD), in the city of Manaus, Brazil. Initially, 180 children aged 6–10 years old participated in this study. After being diagnosed according to the DSM-IV-TR, 63 children were then divided into three groups (21 in each group). Health-related physical fitness was measured by means of the Fitnessgram, which included several core components, namely, body composition, muscle strength and endurance, flexibility, and cardiorespiratory resistance. The results showed no statistically significant differences between both groups in any of the assessed components. However, when analyzing the results of each component according to the criteria of the Fitnessgram, we observed that, regardless of the classification group, less than half of the children achieved scores that, according to the motor tests, would classify them as having a healthy fitness. Children with sDCD, mDCD and wDCD presented similar levels of health-related physical fitness, with an unsatisfactory performance for the component strength and muscular endurance. We therefore emphasize the importance of further research in this area, more particularly when it comes to following the development of motor skills and physical fitness in children with DCD, as well as the observation of the interactions between these variables over time.     

A prospective cohort study comparing workload in children with and without developmental coordination disorder

The purpose of this prospective cohort study was to assess how cardiorespiratory fitness (CRF) of children with probable developmental coordination disorder (DCD) changes over a period of 4.7 years relative to a group of typically developing controls. A school-based sample of children in a large region of Ontario, Canada with 75 out of a possible 92 schools consented to participate. Children enrolled in Grade 4 (mean = 9.9 years, SD = 0.35) at baseline (n = 2278) were followed over the course of 56 months. A total of eight waves of data collection were carried out throughout the study period. The short form of the Bruininks-Oseretsky test of motor proficiency was used to identify children with probable DCD and the maximal speed attained on the Léger 20-m shuttle run to measure CRF. Mixed-effects modeling was used to estimate the change over time in maximal Leger run speed for both groups adjusting for relevant covariates (e.g., gender, BMI, school, activity level, predilection for activity). Children with pDCD had consistently lower maximal run speed relative to controls. The trajectories of run speed in children with probable DCD and those without the disorder differed by gender with pDCD females demonstrating the lowest scores over time. Both genders with probable DCD showed a greater rate of decline in CRF over time relative to the controls. In conclusion, the difference in CRF between children with and without probable DCD is substantial, and it tends to increase over time. This adds to the argument suggesting that interventions intended to improve CRF may be appropriate and necessary for children with motor difficulties.     

Metabolic syndrome in children with and without developmental coordination disorder

Children with developmental coordination disorder (DCD) have higher rates of obesity compared to children with typical motor development, and, as a result may be at increased risk for developing metabolic syndrome (MetS). The purpose of this study was to determine the presence of MetS and its components among children with and without DCD. This nested case-control study classified 63 children scoring below the 16th percentile on the Movement Assessment Battery for Children (M-ABC-2) as probable DCD (pDCD), and 63 controls, all of whom scored above the 16th percentile. Metabolic syndrome was defined using the International Diabetes Federation (IDF) criteria. Eleven children met the criteria for MetS; 8 (72.3%) with pDCD and 3 (27.3%) controls (p = 0.115). Abdominal obesity was found in 39 (30.9%) of children, 29 (46.0%) with pDCD and 10 (15.9%) controls (p < 0.01). Serum triglycerides were higher in pDCD compared to controls, 91.9 mg/dl (63.1) vs. 67.7 mg/dl (33.3) in the control group, p = 0.001. Blood pressure was also significantly higher in the pDCD group, mean systolic BP (110 vs. 105 mmHg, p = 0.01) and mean diastolic BP (69 vs. 65 mmHg, p = 0.01). There were no statistically significant differences between the groups for other components of MetS. The higher prevalence of abdominal obesity and elevated triglycerides and blood pressure in children with pDCD may put them at risk of meeting all criteria of MetS earlier then their peers.     

Participation of children with developmental coordination disorder

Children with developmental coordination disorder (DCD) participate less frequently and in less diverse activities compared to typically-developing children. Participation restrictions have been attributed to poor motor skills, but no studies have examined the influence of the environment on participation of children with DCD. This study examined participation in children with DCD at home, school and in the community, considering both personal and environmental factors.Eighty-one parents of 4- to 12-year-old children with DCD (M = 8.3, SD = 2.1) completed the Participation and Environment Measure-Child and Youth (PEM-CY). Our data were compared to previously published data on typically-developing children. Children with DCD participated less frequently than typically-developing children in school and community settings and had less overall environmental support in all three settings. Regarding improvement in participation, children with DCD would benefit from motor interventions that also focus on modification of the environment to support their participation in home, school, and community settings.     

A staged approach for identifying children with developmental coordination disorder from the population

The purpose of this study was to describe the motor, attention and intellectual characteristics of a population-based sample of children first screened for motor impairment and to discuss the recruitment and identification methods employed. A two stage cross-sectional, school-based survey was conducted to screen for children with motor coordination difficulties and to identify children with an existing diagnosis of attention deficit hyperactivity disorder/attention deficit disorder (ADHD/ADD). The identified children, and a random sample of typically developing children, were assessed to confirm or rule out the presence of developmental coordination disorder (DCD).Six thousand four hundred and seventy five children were invited to participate; 2943 children, with parental consent, completed the initial screening process. Two hundred eighty four children with possible motor impairment were identified. The parents of 113 children consented to a full assessment. Sixty eight children of the 113 children met diagnostic criteria for DCD, and 26 also had ADHD. Twenty eight of the 55 children who screened in with a diagnosis of ADHD were subsequently found to have DCD. The total number of children with confirmed characteristics of DCD was reduced after application of DCD diagnostic criteria. This study differs from others with regard to the additional screening for children with ADHD/ADD. The second stage assessment notably increased the number of children identified with both ADHD and DCD.     

Anxiety profiles in children with and without developmental coordination disorder

Previous work has highlighted that children diagnosed with DCD may be at risk of greater problems related to emotional wellbeing. However, to date much work has relied on population based samples, and anxiety has not been examined within a group of children given a clinical diagnosis of DCD. Additionally, the profile of individual differences has generally not been considered within this group. Therefore, a group of parents (n = 27) completed the parent version of the Spence Children's Anxiety Scale (SCAS-P; Spence, 1998) in relation to their children with a diagnosis of DCD. Their responses on this measure were compared to those of parents with typically developing (TD) children (n = 35; both groups 6-15 years of age). Children diagnosed with DCD were reported to experience significantly greater levels of anxiety overall, as well as having significantly greater difficulty than the TD group in the domains of panic/agoraphobic anxiety, social phobia, and obsessive compulsive anxiety. In addition, the individual profiles of types of anxiety reportedly experienced varied widely across the DCD group. These findings suggest that anxiety is a major problem for a proportion of children diagnosed with DCD, and raises questions regarding intervention, long term outcomes, and the nature of the disorder itself.     

Obesity and motor coordination ability in Taiwanese children with and without developmental coordination disorder

The purpose of this study was to investigate the associations between obesity and motor coordination ability in Taiwanese children with and without developmental coordination disorder (DCD). 2029 children (1078 boys, 951 girls) aged nine to ten years were chosen randomly from 14 elementary schools across Taiwan. We used bioelectrical impedance analysis to measure percentage of body fat (PBF) and the Movement Assessment Battery for Children test (MABC test) to evaluate the motor coordination ability. Using cut-off points based on PBF from past studies, boys and girls were divided into obese, overweight and normal-weight groups, respectively. In boys, total impairment scores and scores on balance subtest in the MABC were significantly higher in the obese and overweight groups when compared against the normal-weight group. Girls in the obese and the overweight groups had higher balance impairment scores than those of the normal-weight group. Among boys, the prevalence of obesity was highest in the DCD group, when compared to the borderline DCD and TD boys. A higher percentage of DCD girls were overweight and obese than TD girls. Obesity may be associated with poor motor coordination ability among boys and girls, and particularly in relation to balance ability. Children with DCD may have a higher risk to be overweight or obese in Taiwan.     

Influence of methylphenidate on motor performance and attention in children with developmental coordination disorder and attention deficit hyperactive disorder

Individuals with attention deficit hyperactive disorder (ADHD) often have coexisting developmental coordination disorder (DCD). The positive therapeutic effect of methylphenidate on ADHD symptoms is well documented, but its effects on motor coordination are less studied. We assessed the influence of methylphenidate on motor performance in children with comorbid DCD and ADHD. Participants were 30 children (24 boys) aged 5.10–12.7 years diagnosed with both DCD and ADHD. Conners’ Parent Rating Scale was used to reaffirm ADHD diagnosis and the Developmental Coordination Disorder Questionnaire was used to diagnose DCD. The Movement Assessment Battery for Children-2 and the online continuous performance test were administrated to all participants twice, with and without methylphenidate. The tests were administered on two separate days in a blind design. Motor performance and attention scores were significantly better with methylphenidate than without it (p < 0.001 for improvement in the Movement Assessment Battery for Children-2 and p < 0.006 for the online continuous performance test scores).The findings suggest that methylphenidate improves both attention and motor coordination in children with coexisting DCD and ADHD. More research is needed to disentangle the causality of the improvement effect and whether improvement in motor coordination is directly affected by methylphenidate or mediated by improvement in attention.     

Wisconsin Card Sorting Test performance in children with developmental coordination disorder

The primary purpose of this study was to investigate and compare the executive functions measured by the Wisconsin Card Sorting Test (WCST) between children with developmental coordination disorder (DCD) and age-matched normal controls. A second purpose was to examine the relations between executive functions and school functions in DCD children. Seventy-one children with DCD and 70 children without motor problems were recruited from 14 public schools. Executive functions and school functions were assessed using the WCST, and the School Function Assessment - Chinese Version (SFA-C) respectively. Univariate analyses demonstrated significant between-group differences in five WCST measures. The logistic regression analysis showed differences between two groups on eight SFA-C subscales, and significant correlation between items measured on WCST and SFA-C was also found. The result of the study provides further evidence of impaired sub-domains of executive functions (i.e., mental shifting, flexibility) in children with DCD. The finding also adds to recent investigations into the relationship between executive functions and school functions in DCD. Implications for rehabilitation professionals and recommendations for further research are discussed.     

Assessment of cardiorespiratory and neuromotor fitness in children with developmental coordination disorder

The decreased participation in physical activity by children with probable developmental coordination disorder (pDCD) has raised concerns about their aerobic fitness and lung function levels. The purpose of the present study was to examine assessment of cardiorespiratory and neuromotor fitness, using laboratory-based tests during an incremental treadmill protocol in healthy children with and without pDCD. Twenty sex children ages 6–9 years took part in this study. Motor coordination was assessed using the Movement Assessment Battery for Children (MABC). All participants performed a cardiopulmonary exercise test (CPET) on a cycle ergometer. Pulmonary function was assessed by spirometric measurements (forced vital capacity: FVC, forced expiratory volume in 1 s: FEV₁) and walking distance (6MWD) was assessed using the 6-min walking test. The children with pDCD had lower VO_2 max than children without pDCD (p < 0.01). Moreover, FVC and FEV₁ were significantly higher in children without pDCD than in children with the disorder (p < 0.05, p < 0.01 respectively). Likewise, children with pDCD had poorer performance on the 6MWD than children without pDCD (p < 0.01). A significant correlation between the absolute value for FEV₁ and 6MWD (r = 0.637, p < 0.05) in pDCD group was observed. We found a significant correlation between VO_2 max and MABC score (r = −0.612, p < .001) and between VO_2 max and 6MWD (r = 0.502, p < .001) for all children. Moreover, a significant correlation between VO_2 max and FEV₁ (r = 0.668, p < .05) was found in children with pDCD. Overall, the reduced aerobic capacity of DCD was associated with decreased of lung function, as well as an alteration of peripheral muscle responses.     

Submaximal oxygen cost during incremental exercise in children with developmental coordination disorder

There has been minimal evidence examining the differences in submaximal aerobic power between children with and without probable developmental coordination disorder (pDCD). This is important as most activities of daily living are performed at submaximal levels. The aim of this study was to examine the oxygen cost of work (VO₂) performed during an incremental exercise protocol on a cycle ergometer. Subjects with pDCD (n = 63) were matched for age and gender to 63 typically developing controls (12–13 years of age) using a nested case–control design. Motor coordination was assessed using the Movement Assessment Battery for Children. Children with pDCD had significantly lower VO2 peak values relative to controls (35.0 vs. 42.9 ml/kg/min, p < 0.0001). At the submaximal level, mixed effects modeling demonstrated that, after controlling for relative body fat, and VO₂ peak, children with pDCD had consistently greater oxygen cost (VO₂ ml/kg/min) compared to controls at any given exercise intensity (p = 0.0006). A significant interaction between pDCD and workload indicated that the difference in VO₂ at higher workloads is greater than that at lower workloads (p = 0.0004). Children with pDCD utilize more oxygen to sustain the same submaximal workload. The implication of these findings is that children with pDCD may experience earlier fatigue than well coordinated individuals when engaging in physical activity.     

Assessment of physical fitness and exercise tolerance in children with developmental coordination disorder

Children with developmental coordination disorder (DCD) have been shown to be less physically fit when compared to their typically developing peers. The purpose of the present study was to examine the relationships among body composition, physical fitness and exercise tolerance in children with and without DCD. Thirty-seven children between the ages of 7 and 9 years participated in this study. Participants were classified according to results obtained on the Movement Assessment Battery for Children (MABC) and were divided in 2 groups: 19 children with DCD and 18 children without DCD. All children performed the following physical fitness tests: The five-jump test (5JT), the triple-hop distance (THD) and the modified agility test (MAT). Walking distance was assessed using the 6-min walking test (6MWT). Children with DCD showed higher scores than children without DCD in all MABC subscale scores, as well as in the total score (p < 0.001). Participants with DCD were found to perform significantly worse on the MAT (p < 0.001), the THD (p < 0.001) and 5JT (p < 0.05). Moreover, children with DCD had poorer performance on the 6MWT than children without DCD (p < 0.01). Our results found significant correlations among body mass index (BMI), THD (r = 0.553, p < 0.05), 5JT (r = 0.480, p < 0.05) and 6MWT (r = 0.544, p < 0.05) only in DCD group. A significant correlation between MAT and 5JT (r = −0.493, p < 0.05) was found. Similarly, THD and 5JT (r = 0.611, p < 0.01) was found to be correlated in children with DCD. We also found relationships among 6MWT and MAT (r = −0.522, p < 0.05) and the 6MWT and 5JT (r = 0.472, p < 0.05) in DCD group. In addition, we found gender specific patterns in the relationship between exercise tolerance, explosive strength, power, DCD, and BMI. In conclusion, the present study revealed that BMI was indicative of poorer explosive strength, power and exercise tolerance in children with DCD compared to children without DCD probably due to a limited coordination on motor control.     

Postural responses to a moving room in children with and without developmental coordination disorder

Children (10 or 11 years old) with and without developmental coordination disorder (DCD) were exposed to imposed optic flow in a moving room. We manipulated the amplitude and frequency of oscillatory room motion, and we evaluated the coupling of standing body sway with room oscillations. The results revealed that standing sway of both children with and without DCD was influenced by room motion. However, children with DCD responded differently than children without DCD to specific combinations of room motion amplitude and frequency. We conclude that DCD can influence a child's use of imposed optic flow for postural control and that these effects are situation-specific rather than being systemic.     

Left ventricular structure and function in children with and without developmental coordination disorder

Children with developmental coordination disorder (DCD) are more likely to develop cardiovascular disease risk factors such as obesity and reduced cardio-respiratory fitness. However, there is limited data using laboratory measures for assessing the risk of cardiovascular disease associated with DCD. The purpose of this study was to examine differences in left ventricular structure and function between children with DCD and healthy controls. The study involved 126 children (aged 12-13 years) with significant motor impairment (n = 63) and healthy controls (n = 63) matched for age, sex, and school. The Movement ABC test (M-ABC2) was used to classify children as probable DCD (p-DCD). Cardiac dimensions were measured using ultrasound echocardiography. Left ventricular mass (LVM) was elevated in children with p-DCD (89 ± 17 g) compared to controls (87 ± 21 g), however, this difference was not significant. When LVM was normalized to height^2.7, no difference was evident between groups (26 g and 26 g for the p-DCD and controls, respectively). However, the p-DCD group demonstrated significantly elevated stroke volume (p = 0.02), cardiac output (p < 0.001), end-diastolic volume (p = 0.03), and left ventricle diameter in diastole (p = 0.02). Also, peak VO₂ normalized for fat free mass (FFM) was significantly lower (p = 0.001) and systolic blood pressure (p = 0.01), body mass index (p = 0.001), heart rate (p = 0.005) and percent body fat (p < 0.001) were significantly higher in p-DCD. In regression analyses, p-DCD was a significant predictor of stroke volume and cardiac output even after accounting for height, FFM, VO_2FFM, and sex. Children with p-DCD do not demonstrate significantly elevated LVM or depressed systolic function compared to healthy controls. However, cases with p-DCD demonstrate significantly elevated end-diastolic volume, diastolic chamber size, stroke volume, and cardiac output. These differences indicate obesity related changes in the left ventricle and may represent the early stages of developing left ventricle hypertrophy.     

Bimanual coordination and limb-specific parameterization in patients with Parkinson's disease

Bimanual coordination and the capability to parameterize the individual limb movements were examined in patients with Parkinson's disease (PD) as compared to healthy control subjects. In-phase and anti-phase patterns were performed while the individual limb movements were subjected to amplitude and loading manipulations. Findings showed that PD patients produced the bimanual configurations with lower degrees of phasing accuracy and consistency than control subjects, indicating an impairment at the global (coordinative) level of simultaneously produced movements. At the local (limb-specific) level, the imposed distances with and without loading were unaffected in PD patients as compared to control subjects, whereas cycle times were prolonged and depended on the task requirements. This illustrates a disturbance at the limb-specific level in complying with the execution of the submovements. The finding that movement slowness only became evident in the more complex conditions, suggests that it did not mainly represent a deficit in the execution of coordinated movements, but rather an inability to accommodate the motor output during stringent spatiotemporal task constraints.     

High risk for obesity in children with a subtype of developmental coordination disorder

The purpose of this study was to compare the prevalence of overweight and obesity in typically developing (TD) children, children with developmental coordination disorder (DCD) and balance problems (DCD-BP), and children with DCD without balance problems (DCD-NBP). Two thousand and fifty-seven children (1095 boys, 962 girls) ages 9–12 years were recruited from 18 elementary schools in Taiwan. The Movement Assessment Battery for Children was used to assess motor coordination ability. International cut-off points for body mass index were used to classify participants into the following groups: normal-weight, overweight or obese. Compared with TD children, children in the DCD-BP group were more than twice as likely to be obese (OR = 2.28; 95% CI = 1.41–3.68). DCD-BP children were also more likely to be obese compared to DCD-NBP children (OR = 1.79; 95% CI = 1.02–3.16). Boys in the DCD-BP group were more likely to be obese when compared to DCD-BP girls (OR = 3.12; 95% CI = 1.28–7.57). Similarly, DCD-NBP boys were more likely to be obese when compared to DCD-NBP girls (OR = 2.67; 95% CI = 1.21–5.89). Children with both DCD and BP were significantly more likely to be obese when compared to TD and DCD-NBP children. From an intervention perspective, the inclusion of regular physical activity, including activities that encourage development of both balance and energy expenditure, may be required to prevent obesity in this population.     

Physical activity and fitness in children with developmental coordination disorder: a systematic review

Developmental coordination disorder (DCD) is a neurodevelopmental condition characterized by poor motor proficiency that interferes with a child's activities of daily living. Activities that most young children engage in such as running, walking, and jumping are important for the proper development of fitness and overall health. However, children with DCD usually find these activities challenging. A systematic review of the literature was conducted to synthesize the recent available data on fitness and physical activity in children with DCD, and to understand the extent of the differences between children with DCD and their typically developing peers. Systematic searches of electronic databases and reference lists identified 40 peer-reviewed studies meeting the inclusion criteria. These studies were reviewed in terms of: (a) study design, (b) population, (c) assessment tools, (d) measures, and (e) fitness and physical activity outcomes. It has been demonstrated that body composition, cardiorespiratory fitness, muscle strength and endurance, anaerobic capacity, power, and physical activity have all been negatively associated, to various degrees, with poor motor proficiency. However, differences in flexibility were not conclusive as the results on this parameter are mixed. Studies’ limitations and the impact of results on future work are discussed.