Anxiety in young children with Williams syndrome: a longitudinal study

Highlights: What are the main findings? Anxiety symptomology is highly prevalent in very young children with Williams syndrome, and seems to increase with age/over time (with many children developing co-occurring anxiety disorder symptoms). Our longitudinal findings also provide evidence for the contribution of environmental factors on the nature, developmental course, and maintenance of anxiety, notably, chronological age, sex, and IQ. What is the implication of the main finding? The importance of screening the Williams syndrome population at a very early age and allows clinicians to identify those most at risk of developing an anxiety disorder. The existing anxiety classification systems should be reviewed to reflect specific symptomology in young children with intellectual disabilities or delayed verbal skills, and implications for early intervention programmes aimed at reducing anxiety risk in Williams syndrome individuals. Background/Objectives: Anxiety is a hallmark feature of Williams syndrome (WS), with very high prevalence rates of generalised anxiety disorder (GAD) and specific phobias in both school-aged children and adults, yet a relatively lower prevalence of social phobia. There is very limited research on anxiety in very young children with WS, and no study to date has examined the early prevalence and development of different anxiety disorders in WS. The present research provides a comprehensive assessment of the prevalence and longitudinal profile of anxiety symptomology in very young children with WS. Potential environmental and demographic correlates of anxiety symptomology were also explored. Methods: Participants included 19 young children with WS, aged between 2 and 5 years (at initial testing), who completed a comprehensive developmental assessment. Parents/guardians also completed the Spence Children’s Anxiety Scale (SCAS; Spence, 1997 & Spence et al., 2001), a standardised, psychometrically robust anxiety questionnaire (commonly utilised in research and clinical settings) that measures anxiety symptomology for various anxiety disorders present in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5; American Psychiatric Association, 2013). Results: The present research found anxiety symptomology to be highly prevalent in very young children with WS, particularly GAD and specific phobia. Moreover, the prevalence of anxiety symptomology increased with age and over time, with many children developing comorbid anxiety disorder symptoms approximately 3.5 years later, at Time 2. Chronological age, sex, and developmental/intellectual capabilities were also found to impact on the developmental trajectory of anxiety in young children with WS. Conclusions: The longitudinal findings provide evidence for the contribution of environmental factors on the nature, developmental course, and maintenance of anxiety. Considerable individual variability was apparent, confirming the importance of individual assessments and developing individualised treatment programmes for those with WS.