Are motor coordination deficits an underlying cardinal feature of Autism Spectrum Disorders (ASD)? Database searches identified 83 ASD studies focused on motor coordination, arm movements, gait, or ...postural stability deficits. Data extraction involved between-group comparisons for ASD and typically developing controls (
N
= 51). Rigorous meta-analysis techniques including random effects models, forest and funnel plots,
I
2
, publication bias, fail-safe analysis, and moderator variable analyses determined a significant standardized mean difference effect equal to 1.20 (SE = 0.144;
p
< 0.0001;
Z
= 10.49). This large effect indicated substantial motor coordination deficits in the ASD groups across a wide range of behaviors. The current overall findings portray motor coordination deficits as pervasive across diagnoses, thus, a cardinal feature of ASD.
Abstract Despite a history of a lateral ankle sprain, some individuals (copers) return to high-level activities (i.e. jumping, pivoting) without recurrent injury or loss of function while others ...develop chronic ankle instability (CAI). Understanding the differences between these groups may provide insight into the mechanisms of CAI. The objectives of this investigation were to: (1) compare traditional center of pressure COP, time-to-boundary TTB, and center of pressure–center of mass COP–COM moment arm measures of postural control among controls, established copers, and subjects with CAI and (2) determine the accuracy of these postural control measures at discriminating between established copers and subjects with CAI using receiving operating characteristic curves. 48 subjects (control = 16, coper = 16, CAI = 16) completed two, 30-s trials of single-leg stance on a force plate with their eyes open. Coper and CAI subjects stood on their involved limb while controls stood on a matched limb. The results indicated that mediolateral ( p < 0.01) and anteroposterior ( p < 0.01) COP velocity was greater in individuals with CAI relative to both copers and controls. Similarly, the peak COP–COM moment arm in the anteroposterior direction ( p < 0.01) and the resultant mean COP–COM moment arm ( p < 0.01) were increased in individuals with CAI relative to copers. These measures also reached asymptotic significance ( p < 0.05) indicating that they successfully discriminated between established copers and individuals with CAI.
Abstract Background Postural control deficits in individuals with Autism Spectrum Disorders (ASD) are widely acknowledged; however, the underlying biomechanical features of these deficits remain ...unknown. Nonlinear analyses provide insight into the nature of how movement is controlled and have the potential to provide new insight into the postural control abnormalities associated with ASD. The purpose of this study was to further investigate postural control deficits in children with ASD through linear and nonlinear analyses of center of pressure (COP) data. Methods We evaluated COP data during quiet standing for 16 children with ASD and 17 age-matched typically developing (TD) children. The magnitude of COP fluctuations (COP ranges, velocity, and sway area) and complexity of postural control dynamics, quantified by multiscale entropy (MSE), were compared across groups. Results Children with ASD displayed larger fluctuations in their COP data, observed in COP ranges (95.5% mediolaterally and 46.9% anteroposteriorly, p < 0.05 respectively) and COP sway area (885%, p < 0.05). Children with ASD also displayed less complexity in their COP data, observed in the MSE complexity index ( CI ) (32.4% mediolaterally and 35.7% anteroposteriorly, p < 0.05 respectively). Conclusions The present study successfully revealed that children with ASD have more repetitive patterns in their COP data, indicating a less complex control of posture, on multiple time scales, during quiet stance. These findings suggest a more regular or restricted control of posture and may be an initial step in linking postural instability to stereotypic behavior and the neurobiology of ASD.
There is strong evidence that leisure-time physical activity is protective against postmenopausal breast cancer risk but the association with premenopausal breast cancer is less clear. The purpose of ...this study was to examine the association of physical activity with the risk of developing premenopausal breast cancer.
We pooled individual-level data on self-reported leisure-time physical activity across 19 cohort studies comprising 547,601 premenopausal women, with 10,231 incident cases of breast cancer. Multivariable Cox regression was used to estimate hazard ratios (HRs) and 95% CIs for associations of leisure-time physical activity with breast cancer incidence. HRs for high versus low levels of activity were based on a comparison of risk at the 90th versus 10th percentiles of activity. We assessed the linearity of the relationship and examined subtype-specific associations and effect modification across strata of breast cancer risk factors, including adiposity.
Over a median 11.5 years of follow-up (IQR, 8.0-16.1 years), high versus low levels of leisure-time physical activity were associated with a 6% (HR, 0.94 95% CI, 0.89 to 0.99) and a 10% (HR, 0.90 95% CI, 0.85 to 0.95) reduction in breast cancer risk, before and after adjustment for BMI, respectively. Tests of nonlinearity suggested an approximately linear relationship (
= .94). The inverse association was particularly strong for human epidermal growth factor receptor 2-enriched breast cancer (HR, 0.57 95% CI, 0.39 to 0.84;
= .07). Associations did not vary significantly across strata of breast cancer risk factors, including subgroups of adiposity.
This large, pooled analysis of cohort studies adds to evidence that engagement in higher levels of leisure-time physical activity may lead to reduced premenopausal breast cancer risk.
Restricted, repetitive behaviors (RRBs) are one of the core diagnostic criteria of autism spectrum disorders (ASD), and include simple repetitive motor behaviors and more complex cognitive behaviors, ...such as compulsions and restricted interests. In addition to the core symptoms, impaired movement is often observed in ASD. Research suggests that the postural system in individuals with ASD is immature and may never reach adult levels. RRBs have been related to postural sway in individuals with mental retardation. Our goals were to determine whether subjects with ASD had greater postural sway and whether RBS-R scores were related to the magnitude of postural sway. We compared the center of pressure (COP) sway area during quiet stance with scores on the Repetitive Behavior Scale-Revised (RBS-R) in children with ASD and typically developing (TD) controls ages 3-16. All subjects had Non-verbal IQ > 70. Subjects performed four quiet stance trials at a self-selected stance width for 20 s. Subjects with ASD had greater postural sway area compared to controls. Not surprisingly, subjects with ASD exhibited greater frequencies and intensities of RRBs overall and on all six subscales. Further, there was a positive correlation between postural sway area and presence of RRBs. Interestingly, results of the postural sway area for the ASD group suggests that roughly half of the ASD subjects scored comparable to TD controls, whereas the other half scored >2 SD worse. Motor impaired children did not have significantly worse IQ scores, but were younger and had more RRBs. Results support previous findings of relationships between RRBs and postural control. It appears that motor control impairments may characterize a subset of individuals with ASD. Better delineation of motor control abilities in individuals with ASD will be important to help explain variations of abilities in ASD, inform treatment, and guide examination of underlying neural involvement in this very diverse disorder.
Abstract The purpose of this study was to investigate postural control in children with Autism Spectrum Disorders (ASD) during static and dynamic postural challenges. We evaluated postural sway ...during quiet stance and the center of pressure (COP) shift mechanism during gait initiation for 13 children with ASD and 12 age-matched typically developing (TD) children. Children with ASD produced 438% greater normalized mediolateral sway ( p < 0.05) and 104% greater normalized anteroposterior sway ( p < 0.05) than TD children. Consequently, normalized sway area was also significantly greater ( p < 0.05) in the group with ASD. Similarly, the maximum separation between the COP and center of mass (COM) during quiet stance was 100% greater in the anteroposterior direction ( p < 0.05) and 146% greater in the resultant direction ( p < 0.05) for children with ASD. No significant difference was observed in the mediolateral direction, in spite of the 123% greater separation detected in children with ASD. During gait initiation, no group differences were detected in the posterior COP shift mechanism, suggesting the mechanism for generating forward momentum is intact. However, significantly smaller lateral COP shifts ( p < 0.05) were observed in children with ASD, suggesting instability or an alternative strategy for generating momentum in the mediolateral direction. These results help to clarify some discrepancies in the literature, suggesting an impaired or immature control of posture, even under the most basic conditions when no afferent or sensory information have been removed or modified. Additionally, these findings provide new insight into dynamic balance in children with ASD.
A high body mass index (BMI, kg/m2) is associated with decreased risk of breast cancer before menopause, but increased risk after menopause. Exactly when this reversal occurs in relation to menopause ...is unclear. Locating that change point could provide insight into the role of adiposity in breast cancer etiology.
We examined the association between BMI and breast cancer risk in the Premenopausal Breast Cancer Collaborative Group, from age 45 up to breast cancer diagnosis, loss to follow-up, death, or age 55, whichever came first. Analyses included 609,880 women in 16 prospective studies, including 9956 who developed breast cancer before age 55. We fitted three BMI hazard ratio (HR) models over age-time: constant, linear, or nonlinear (via splines), applying piecewise exponential additive mixed models, with age as the primary time scale. We divided person-time into four strata: premenopause; postmenopause due to natural menopause; postmenopause because of interventional loss of ovarian function (bilateral oophorectomy (BO) or chemotherapy); postmenopause due to hysterectomy without BO. Sensitivity analyses included stratifying by BMI in young adulthood, or excluding women using menopausal hormone therapy.
The constant BMI HR model provided the best fit for all four menopausal status groups. Under this model, the estimated association between a five-unit increment in BMI and breast cancer risk was HR=0.87 (95% CI: 0.85, 0.89) before menopause, HR=1.00 (95% CI: 0.96, 1.04) after natural menopause, HR=0.99 (95% CI: 0.93, 1.05) after interventional loss of ovarian function, and HR=0.88 (95% CI: 0.76, 1.02) after hysterectomy without BO.
The BMI breast cancer HRs remained less than or near one during the 45–55 year age range indicating that the transition to a positive association between BMI and risk occurs after age 55.
•Between 45 and 55 years of age, the BMI breast cancer HR varied little across age-time.•After natural menopause, the BMI breast cancer time-dependent HR remained near null.•The rise to a positive BMI breast cancer HR may be gradual and occur after age 55.
Advance Clinical and Translational Research (Advance-CTR) serves as a central hub to support and educate clinical and translational researchers in Rhode Island. Understanding barriers to clinical ...research in the state is the key to setting project aims and priorities.
We implemented a Group Concept Mapping exercise to characterize the views of researchers and administrators regarding how to increase the quality and quantity of clinical and translational research in their settings. Participants generated ideas in response to this prompt and rated each unique idea in terms of how important it was and feasible it seemed to them.
Participants generated 78 unique ideas, from which 9 key themes emerged (e.g.,
). Items rated highest in perceived importance and feasibility included providing seed grants for pilot projects, connecting researchers with common interests and networking opportunities. Implications of results are discussed.
The Group Concept Mapping exercise enabled our project leadership to better understand stakeholder-perceived priorities and to act on ideas and aims most relevant to researchers in the state. This method is well suited to translational research enterprises beyond Rhode Island when a participatory evaluation stance is desired.
To evaluate the impact of power assist wheels on the distance traveled by manual wheelchair users and analyze potential cofactors in the magnitude of response and to test the hypothesis that wheelers ...would travel significantly further with power assist wheels.
A 16-wk A (Preintervention)-B (Intervention)-A (Postintervention) repeated measures design. Seven women and 13 men (age, 43 +/- 15 yrs) full-time wheelers participated. During the pre- and postintervention phases (4 wks each), participants used their own unaltered manual wheelchairs. During the 8-wk intervention phase, the manual wheels were replaced with power assist wheels. Daily distance was measured with bicycle-style odometers. A composite score of laboratory wheelchair tasks was used to classify wheelchair performance. Mixed model repeated measures analysis of variance analyzed changes across phases of the trial. A post hoc analysis tabulated the amount of days wheelers exceeded their individual daily averages in each phase by two SDs.
Wheelers traveled significantly greater distances during the intervention phase compared with pre- or postintervention phases regardless of baseline wheelchair performance. Wheelers who demonstrated higher baseline wheelchair performance traveled lesser average distances in the first 2 wks after receiving power assist wheels than in the subsequent 6 wks. Wheelers exceeded their individual daily averages per phase on a significantly greater number of days during the intervention phase.
Power assist wheels enabled wheelers to travel farther and to travel beyond their usual distances on more days. Further studies may be strengthened by taking into account the 2-wk "adjustment phase" for power assist wheels.
PDF
