Prevalence of Neurodevelopmental Disorders in a Homeless Population - Pilot Study

Scientific justification : The main neurodevelopmental disorders (NDDs) are Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder (ADHD), Intellectual Disability (ID), Specific Learning Disorders and Neurodevelopmental Motor Disorders. This study will focus on three NDDs: ASD, ADHD and ID. Cleaton & Kirby (2018) point out an accumulation and adversity problematic: people with NDDs would accumulate problems over time "in a cascading and cumulative manner" that would lead to adverse medical, psychological and psychosocial outcomes. Many studies have shown the poor outcomes in NDDs. People with ADHD have higher risks of imprisonment (Young & Thome, 2011), poor educational achievement (Fleming et al., 2017), thus unemployment (Halmøy et al., 2009), leading to poor quality of life (Agarwal et al., 2012). ASD has also been linked to unemployment (Bush & Tassé, 2017) or at least to low earnings (Roux et al., 2013), leading to lower quality of life (Ikeda et al., 2014). Unsurprisingly, ID has also been showed to lead to poorer quality of life (Simões & Santos, 2016), because of the higher risk of risky behaviours (Fogden et al., 2016). Thus, all these reasons can lead to social isolation, difficulties in establishing independent living and vulnerability. Homelessness can arise from vulnerability, as much as it can cause it. Homelessness refers to rough sleeping (to sleep in the open air or in places not intended for human habitation, Crisis, 2017.), but also to people who sleep in adapted sleeping places but who do not have any official title to the accommodation (Fazel et al., 2014). A recent French study (Laporte et al., 2018) concluded that more than 30% of homeless people suffer from mental health disorder (13.2% would have psychosis, 12.3% severe anxiety disorder, 6.7% severe mood disorder). There is an increasing number of studies linking mental health and homelessness, however research on NDDs and homelessness is still rather poor. Two British studies have found a high prevalence of ASD among homeless adults. They explain this prevalence by the difficulty for these people to get and keep a job (Churchard et al., 2018; Kargas et al., 2019). Kargas et al., 2019 have found that 18.5% of their homeless population presented with scores superior to 7 at the AQ-10, consistent with high levels of autistic traits. A prospective study has shown that out of 135 children with ADHD, 23.9% have known homelessness at least once in their adult life (García Murillo et al., 2016). Riglin et al., (2023) explain that 20% of young socially precarious adults would suffer from ADHD. Durbin et al., (2018) claim that the prevalence of ID in a homeless population would be between 12 and 39%, this is corroborated by Brown & McCann., (2021) who point out that 10 to 39% of homeless people would have an ID. These international studies point out the probable links between homelessness and NDDs, however this field of research is lacking in France.

Main aim of the study : to study the prevalence of the following 3 NDDs (ASD, ADHD, IDD) in a homeless population received in accommodation and social rehabilitation centres

Secondary aims :

1. To compare the social, demographic, medical and judicial characteristics of homeless people with NDD and homeless people without NDD.
2. To research the frequency of traumatic brain injury, coma and epilepsy in this homeless NDD population.

Methodology :