Comorbidity Clusters in Autism Spectrum Disorders: An Electronic Health Record Time-Series Analysis
http://pediatrics.aappublications.org/content/early/2013/12/03/peds.2013-0819
Some important points from the full paper – Wake State Cohort / Boston Cohort
Mental retardation 28.3 – 16.2
Seizure 21.7 – 21.5
Psychiatric disorders 4.9 – 7.5
Gastrointestinal disorders 5.7 – 5.1
Muscular dystrophy 0.6 – 1.4
Sleep disorders 9.1 – 9.7
Auditory disordersand infections 31.5 – 28.2
Cardiac disorders 5.5 – 9.6
Asperger proportion
Group 1 0.4
Group 2 0.5
Group 3 0.8
Group 4 0.5
Subgroup 1
* Seizures present in 77.5% of individuals
* Lowest proportion of Boys
* High Rate of Intellectual Disability 60%
Subgroup 2
* Correlation with cardiac and auditory disorders, asthma and other autoimmune
disorders,and congenital anomalies involving the ear, eye, and cranial nerve.
* Characterized by “relatively severe” autism
* Abnormal immune response to infection
* Increased ear infections
Subgroup 3
* Highest rate of individuals with Asperger’s Syndrome
* Lowest rate of Intellectual Disability
* Comorbidities largely psychiatric disorders (especially anxiety).
* Non- psychiatric comorbidities – asthma and cardiac dysrhythmia.
————————————
The statistics are more complex than summary indicates …
Seizures by sub groups –
Group 1 77.50 (70.03–84.97)
Group 2 42.13 (35.24–49.03)
Group 3 33.02 (26.69–39.35)
Group 4 18.16 (17.01–19.32)
Gastrointestinal Disorders
Group 1 14.17 (7.93–20.41)
Group 2 24.37 (18.37–30.36)
Group 3 10.85 (6.66–15.04)
Group 4 3.43 (2.89–3.97
“The prevalence of the comorbidities described in here are higher in the ASD
population than in the general pediatric population, even in tertiary care centers,5 and echo the differences between essential and complex ASDs described by Miles et al.33 Thus, although these co-occurrence patterns may occur for many reasons (a disease, or its treatment, may make the patient more vulnerable for another; genetic variants may have pleiotropic effects that include autism and other comorbidities; and environmental insults may also have pleiotropic effects), we do not believe these findings are simply incidental.”
