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Downes, Michelle
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Downes, Michelle
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Downes, Michelle
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- PublicationOutcome following multiple subpial transection in Landau-Kleffner syndrome and related regressionObjective: To determine whether multiple subpial transection in the posterior temporal lobe has an impact on long-term outcome in children who have drug-resistant Landau-Kleffner syndrome (LKS) or other "electrical status epilepticus during sleep" (ESES)-related regression. Given the wide variability in outcomes reported in the literature, a secondary aim was to explore predictors of outcome. Methods: The current study includes a surgery group (n = 14) comprising patients who underwent multiple subpial transection of the posterior temporal lobe and a nonsurgery comparison group (n = 21) comprising patients who underwent presurgical investigations for the procedure, but who did not undergo surgery. Outcomes were assessed utilizing clinical note review as well as direct assessment and questionnaires. Results: The distribution of nonclassical cases was comparable between groups. There were some differences between the surgery and nonsurgery groups at presurgical investigation including laterality of discharges, level of language impairment, and age; therefore, follow-up analyses focused on change over time and predictors of outcome. There were no statistically significant differences between the groups in language, nonverbal ability, adaptive behavior, or quality of life at follow-up. There was no difference in the proportion of patients showing improvement or deterioration in language category over time for either group. Continuing seizures and an earlier age of onset were most predictive of poorer quality of life at long-term follow-up (F2,23 = 26.2, p = <0.001, R2 = 0.714). Significance Both surgery and nonsurgery groups had similar proportions of classic LKS and ESES-related regression. Because no significant differences were found in the changes observed from baseline to follow-up between the two groups, it is argued that there is insufficient evidence to suggest that multiple subpial transection provides additional benefits over and above the mixed recovery often seen in LKS and related regressive epilepsies.
269Scopus© Citations 20 - PublicationPrevalence and risk factors for autism spectrum disorder in epilepsy: a systematic review and meta‐analysisAim: To assess the prevalence and risk factors for autism spectrum disorder (ASD) in epilepsy, and to better understand the relationship and comorbidity between these disorders. Method: PsychINFO and PubMed were searched for articles published in the past 15 years that examined the prevalence of ASD in individuals with epilepsy. Results: A total of 19 studies were found with a pooled ASD prevalence of 6.3% in epilepsy. When divided by type, the risks of ASD for general epilepsy, infantile spasms, focal seizures, and Dravet syndrome were 4.7%, 19.9%, 41.9%, and 47.4% respectively. Studies with populations under 18 years showed a 13.2 times greater risk of ASD than study populations over 18 years, and samples with most (>50%) individuals with intellectual disability showed a greater risk 4.9 times higher than study populations with a minority of individuals with intellectual disability. The main risk factors for ASD reported in the 19 studies included presence of intellectual disability, sex, age, and symptomatic aetiology of epilepsy. Interpretation: Current research supports a high prevalence of ASD in epilepsy. This study helps to define the clinical profile of patients with epilepsy who are at risk for ASD, which may help clinicians in early screening and diagnosis of ASD in this population. What this paper adds: • Critical evaluation of previous studies examining the prevalence of autism spectrum disorder (ASD) in individuals with epilepsy. • A meta‐analysis of 19 studies showed a pooled ASD prevalence of 6.3% in individuals with epilepsy. • Studies that included a majority of individuals with intellectual disability or younger population age had a higher prevalence of autism. • Risk factors reported in studies included presence of intellectual disability, sex, age, and symptomatic epilepsy origin.
210Scopus© Citations 79 - PublicationIn response: Comment on outcome following multiple subpial transection in Landau-Kleffner syndrome and related regressionWe thank Dr. Kheder and colleagues for their letter and we are grateful for their comments.
246 - PublicationEvent-related potential measures of executive functioning from preschool to adolescenceExecutive functions are a collection of cognitive abilities necessary for behavioural control and regulation, and are important for school success. Executive deficits are common across acquired and developmental disorders in childhood and beyond. This review aims to summarize how studies using event-related potential (ERP) can provide insight into mechanisms underpinning how executive functions develop in children from preschool to adolescence. We specifically focus on ERP components that are considered to be well-established markers of executive functioning, including the ability to resist distraction (inhibition, N200), hold scenes in mind (visuospatial working memory, contralateral delay activity), attend to specific stimuli (information processing, P300), follow rules (response monitoring, error-related negativity [ERN], and error-related positivity [Pe]), and adjust to feedback (outcome monitoring, feedback-related negativity). All of these components show developmental changes from preschool to adolescence, in line with behavioural and neuroimaging findings. These ERP markers also show altered developmental trajectories in the context of atypical executive functions. As an example, deficits in executive function are prominently implicated in attention-deficit–hyperactivity disorder. Therefore, this review highlights ERP studies that have investigated the above ERP components in this population. Overall, ERPs provide a useful marker for the development and dysfunction of executive skills, and provide insight into their neurophysiological basis.
255Scopus© Citations 55 - PublicationSensory modulation difficulties and assessment in children with attention deficit hyperactivity disorder: a systematic review(Taylor & Francis, 2021-03-16)
; ; ; This systematic review aims to (1) establish how different types of assessment measure sensory modulation difficulties in children with ADHD, and (2) to examine whether sensory modulation difficulties can be separated from ADHD symptomatology. The review protocol was registered with PROSPERO (CRD42018091730). PRISMA guidelines were used. Three databases (PsycINFO, PubMed, CINAHL) were searched using a predetermined search string from 1980 to 2020. Twenty-five studies met inclusion criteria. Sensory modulation difficulties are more likely to be reported when caregiver-report or behavioural measures are used, relative to physiological methods. Despite the focus to date on difficulties in auditory and tactile processing in this patient population, the reported studies show no evidence for these difficulties being more prevalent than difficulties in other sensory domains. Caregiver reports show evidence for differences in children with sensory modulation difficulties and ADHD, and those with ADHD only. This review reports variability in the prevalence of sensory modulation difficulties in children with ADHD that is dependent on the tools used to measure this domain. Approaches to the assessment of sensory modulation, and the implications for clinical practice, are considered.180Scopus© Citations 2 - PublicationVisual attention control differences in 12-month-old preterm infantsThere have been few previous attempts to assess the development of early markers of executive function in infants born preterm despite well-established deficits reported for older preterm children that have been closely linked to poorer academic functioning. The present study investigates early attention control development in healthy 12-month-old age-corrected pre-term infants who were born less than 30 weeks and compares their performance to full-term infants. Eye-tracking methodology was used to measure attention control. Preterm Infants spent less time focused on the target and were slower to fixate attention, with lower gestational age associated with poorer target fixation and slower processing speed. There were no significant group differences observed for inhibition of return or interference control. These findings suggest that specific emerging deficits in attention control may be observed using eye tracking methodology in very preterm infants at this early stage of development, despite scores within the average range on the Bayley Scales of Infant Development.
188Scopus© Citations 12 - PublicationAltered Neurophysiological Processing of Auditory Attention in Preschool Children With Sickle Cell Disease(Oxford University Press, 2017-09-01)
; ; ; Objective: Sickle cell disease (SCD) is a genetic red blood cell disorder that often leads to stroke and executive dysfunction in school-age children and adults. This study aimed to characterize the development of the neural correlates of selective attention, an early component of executive function, in preschool children with SCD. Methods: Auditory event-related potentials (ERPs) were recorded while children attended to a story stream in one ear and ignored a second story in the other ear interchangeably. In total, 12 patients (mean age = 5.5, 7 males) and 22 typically developing children (mean age = 4.4, 10 males) were included in the final analyses. Results: By 100 ms, more positive ERP amplitudes were observed for attended relative to unattended stimuli in typically developing children but not those with SCD, suggesting deficits in the ability to focus attention. Reduced attention effects were associated with lower performance intellectual quotient Conclusion: There are deficits in early attention modulation in young children with SCD.281Scopus© Citations 8 - PublicationTemperament in preschool children with sickle cell anaemiaAims: Few studies have investigated the potential impact of sickle cell anaemia (SCA) on temperament. The aim of the current study was to investigate temperament in preschool children with SCA and to establish the reliability of the Children’s Behaviour Questionnaire (CBQ) in this population. Methods: The CBQ, a parent-report measure of temperament was completed by parents of 21 preschool children with SCA and a control group of parents of typically developing children, matched for age, ethnicity, and socio-economic status. Results: A significant difference between groups was identified for the dimension of Negative Affectivity only, with specific differences observed in the Discomfort subdomain. Patients with a greater number of hospital admissions in the previous year were reported to have higher levels of discomfort. Conclusions: Preschool children with SCA are reported to have higher rates of Negative Affectivity, particularly Discomfort. Further research is required to investigate the influence of negative affectivity and discomfort on disease management and quality of life throughout childhood.
264Scopus© Citations 1 - PublicationOvernight auto-adjusting continuous airway pressure + standard care compared with standard care alone in the prevention of morbidity in sickle cell disease phase II (POMS2b): Study protocol for a randomised controlled trialBackground: In addition to pain, sickle cell anaemia (HbSS) complications include neurocognitive difficulties in attention and processing speed associated with low daytime and night-time oxygen saturation compounded by obstructive sleep apnoea (OSA). In the general population OSA is treated with continuous positive airways pressure (CPAP). The aim of this single-blind, randomised, controlled phase II trial is to compare auto-adjusting CPAP (APAP) with standard care to standard care alone in individuals with HbSS to determine whether the intervention improves attention and processing speed, brain structure, pain and quality of life. Methods/Design: Eligibility criteria include: ability to provide informed consent; age>8years; diagnosis of HbSS; and mean overnight saturation of<90% for<30% of the night (i.e. not meeting current criteria for overnight oxygen therapy). Key exclusion criteria are: overnight respiratory support; respiratory or decompensated cardiac failure; chronic transfusion; or contraindications to APAP therapy or magnetic resonance imaging (MRI). Sixty individuals with HbSS (30 children and 30 adults) will be randomised to standard care+APAP or standard care alone for six months. Minimisation factors are: age group (8-11, 12-15, 16-22 and>23years); silent infarction on MRI; minimum overnight oxygen saturation>90% or<90%; and hydroxyurea use. For APAP individuals, the intervention is administered at home. Adherence and effectiveness are recorded using software documenting hours of use each night and overnight oximetry. Participant support in terms of appropriate facemask and facilitating adherence are provided by an unblinded sleep physiologist. The primary outcome is change in the cancellation subtest from the Wechsler scales. Secondary outcomes include general cognitive functioning, quantitative brain MRI, blood and urine chemistry, quality of life and daily pain via a smartphone App (GoMedSolutions, Inc) and, where possible MRI heart, echocardiography, and 6-min walk. These outcomes will be assessed at baseline and after six months of treatment by assessors blind to treatment assignment. Discussion: Altering oxygen saturation in HbSS may lead to bone marrow suppression. This risk will be reduced by monitoring full blood counts at baseline, two weeks, three months and six months, providing treatment as appropriate and reporting as safety events. Trial registration: ISRCTN46012373. Registered on 10 July 2015. Protocol Version: 6.0 Date: 24th December 2015 Sponsor: University Hospital Southampton. Sponsor's protocol code: RHMCHIOT53
196Scopus© Citations 12 - PublicationSensory modulation and negative affect in children at familial risk of ADHDBackground/aims: Sensory modulation difficulties are commonly reported in patients with ADHD, however there has been little focus on the development of these difficulties in young children at a higher risk of later ADHD diagnosis. This study investigated whether children with a familial history of ADHD show greater sensory modulation difficulties. We also explored whether sensory modulation was linked to negative affectivity, which has been highlighted as a potential early marker of ADHD. Methods: Parents of children under 6 years with a family history of ADHD (n = 65) and no family history (n = 122) completed questionnaires on sensory modulation and temperament. Results: Children from families with ADHD were reported to display extreme patterns of hyperresponsiveness and hyporesponsiveness, relative to controls. No differences emerged for the sensory seeking domain. Some children within the high-risk group reported high scores across all three sensory modulation patterns. Regression analysis revealed that hyperresponsiveness predicted higher levels of negative affect. Conclusions/implications: This study is the first to report greater sensory modulation difficulties in children at familial risk of ADHD. Future research should establish whether children with sensory modulation and temperament difficulties in early childhood are more vulnerable to developing ADHD.
121Scopus© Citations 2