Psychiatric Co-morbidities in a French Cohort of Adults with High-functioning Autism (HFA)

Background and rationale

Psychiatric comorbidities are shown to be very prevalent in patients diagnosed with Autism Spectrum Disorder (ASD), up high to 53% for mood, 50% anxiety and 43% for ADHD disorders in an European cohort of adults with HFA. Using a new approach, our study proposes to explore aspects of comorbidities in the largest French cohort of HFA adults (C0733/InfoR) by implying qualitative and quantitative clinical tools.

Aims

To explore: (1) the prevalence rates of psychiatric comorbidities; (2) the interplay between comorbidities and the ASD symptoms.

Methods

Diagnosis was made according to DSM 5 criteria. Dimensional evaluation used Social Responsiveness Scale (SRS), Systemizing Quotient (SQ) and Empathy Quotient (EQ). We used T-test, Mann–Whitney test and linear regression models.

Results

We included 103 patients (mean age 29.3, sex ratio M/F: 3.4:1). Lifetime prevalence rates of 53.5% for depressive disorder 73.5% for anxiety disorders and 37.5% for ADHD were found. Subjects with psychotic co-morbid symptoms had a more severe social deficit (SRS score 66.2 vs 77.9 P < 0.05); patients with ADHD, lower cognition (mean IQ total 107.7 vs 99.0 P < 0.05). SQs (P < 0.05) were significantly higher in patients with co-morbid psychosis, dysthymia, suicide attempts, and depressive disorders and directly correlated with age (β = 0.35, P < 0.05). SQ and EQ were inversely correlated.

Discussion

The results reproduce the high prevalence of comorbidities in other studies and explore its association with social functioning and cognition. Identification of associated psychiatric conditions in subjects with HFA is therefore a crucial clinical issue potentially guiding the treatment.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

CNTN6 mutations are risk factors for abnormal auditory sensory perception in autism spectrum disorders

Contactin genes CNTN5 and CNTN6 code for neuronal cell adhesion molecules that promote neurite outgrowth in sensory-motor neuronal pathways. Mutations of CNTN5 and CNTN6 have previously been reported in individuals with autism spectrum disorders (ASDs), but very little is known on their prevalence and clinical impact. In this study, we identified CNTN5 and CNTN6 deleterious variants in individuals with ASD. Among the carriers, a girl with ASD and attention-deficit/hyperactivity disorder was carrying five copies of CNTN5. For CNTN6, both deletions (6/1534 ASD vs 1/8936 controls; P=0.00006) and private coding sequence variants (18/501 ASD vs 535/33480 controls; P=0.0005) were enriched in individuals with ASD. Among the rare CNTN6 variants, two deletions were transmitted by fathers diagnosed with ASD, one stop mutation CNTN6W923X was transmitted by a mother to her two sons with ASD and one variant CNTN6P770L was found de novo in a boy with ASD. Clinical investigations of the patients carrying CNTN5 or CNTN6 variants showed that they were hypersensitive to sounds (a condition called hyperacusis) and displayed changes in wave latency within the auditory pathway. These results reinforce the hypothesis of abnormal neuronal connectivity in the pathophysiology of ASD and shed new light on the genes that increase risk for abnormal sensory perception in ASD.