Anxiety as a Common Biomarker for School Children With Additional Health and Developmental Needs Irrespective of Diagnosis

The effect of anxiety on working memory and language abilities in elementary schoolchildren with and without Additional Health and Developmental Needs

Although excessive childhood anxiety is recognised as a significant public health, education and socioeconomic concern, the specific effects of such anxiety on language development and working memory, particularly visual working memory, are relatively unknown. Thus, this study aimed to examine parent-reported trait anxiety, parent-reported functional language (daily communication skills) and clinical measures of non-verbal intelligence, receptive and expressive vocabulary, phonological awareness, and visual and auditory-verbal short-term and working memory in elementary schoolchildren. The final sample included 41 children categorised as Additional Health and Developmental Needs (AHDN) due to medical, neurodevelopmental or educational concerns and 41 age- and IQ-matched neurotypical (NT) children, aged 5- to 9-years. Results showed that 26% of all children in our entire sample (AHDN and NT) experienced moderate, sub-clinical anxiety (as reported by parents), and that AHDN children were 10.5 times more likely to experience high anxiety than the NT group (odds ratio). Parents of AHDN children reported lower functional language in their children than parents of NT children. Cognitive testing indicated that the AHDN group also had poorer visual and auditory-verbal working memory than the NT group. Further, High Anxiety children (drawn from both AHDN and NT groups) showed poorer parent-reported functional language skills, and lower visual and auditory-verbal working memory capacities. Our findings are amongst the first to confirm that the presence of high parent-rated trait anxiety is associated with reduced visual working memory in children, which is consistent with biological and theoretical expectations of the impact of anxiety on visually driven, goal-directed attention and working memory. Our results regarding the high prevalence of sub-clinical anxiety in both ADHD and neurotypical children highlight the need for early assessment of anxiety in all schoolchildren, especially those classified as AHDN.

Activated PI3Kδ syndrome, an immunodeficiency disorder, leads to sensorimotor deficits recapitulated in a murine model

The phosphoinositide-3-kinase (PI3K) family plays a major role in cell signaling and is predominant in leukocytes. Gain-of-function (GOF) mutations in the PIK3CD gene lead to the development of activated PI3Kδ syndrome (APDS), a rare primary immunodeficiency disorder. A subset of APDS patients also displays neurodevelopmental delay symptoms, suggesting a potential role of PIK3CD in cognitive and behavioural function. However, the extent and nature of the neurodevelopmental deficits has not been previously quantified. Here, we assessed the cognitive functions of two APDS patients, and investigated the causal role of the PIK3CD GOF mutation in neurological deficits using a murine model of this disease. We used p110δ^E1020K knock-in mice, harbouring the most common APDS mutation in patients. We found that APDS patients present with visuomotor deficits, exacerbated by autism spectrum disorder comorbidity, whereas p110δ^E1020K mice exhibited impairments in motor behaviour, learning and repetitive behaviour patterning. Our data indicate that PIK3CD GOF mutations increase the risk for neurodevelopmental deficits, supporting previous findings on the interplay between the nervous and the immune system. Further, our results validate the knock-in mouse model, and offer an objective assessment tool for patients that could be incorporated in diagnosis and in the evaluation of treatments.