Posted April 18, 2016
Maj Cade Nylund, M.D., USAF, Uniformed Services University of the Health Sciences
With funding provided by a 2011 Pilot Award from the CDMRP Autism Research Program, Dr. Cade Nylund and his team from the Uniformed Services University of the Health Sciences examined Department of Defense Military Health System medical records to understand the comorbid conditions and risk factors for autism.
The researchers studied the records of 48,762 children with Autism Spectrum Disorders (ASDs) ages 2-18 and 243,810 children without ASD, age- and gender-matched, who enrolled in the Military Health System during 2000-2013. Using this data set (one of the largest of military families in the world), Dr. Nylund and his colleagues were able to identify multiple key conditions, more common in children with autism, and a combination of prenatal and early infancy risk factors for the later development of ASD.
Specifically, the researchers found that children with ASD are at considerably increased nutritional risk. They found that children with ASD were more twice as likely to be obese and suffer from its complications including hypertension, high cholesterol, type II diabetes, and fatty liver disease than matched controls. The research suggests that medications prescribed to children with ASD may play a part. Children with ASD also are at risk for nutritional deficiencies in macro- and micronutrients including iron, vitamin A, calcium, vitamin D, and protein. Counterintuitively, some children with ASD are also at increased risk for being underweight.
Common childhood conditions such as ear infections, urinary tract infections, and appendicitis are more likely to have complications in children with ASD. Children with ASD have difficulty in communicating their physical concerns to parents and physicians, which leads to missed or late diagnosis.
The researchers found that over 80% of children with ASD were diagnosed with a mental health condition compared to 30% of controls; over 65% of children with ASD were on psychiatric medications at some point in the study and more than 9 times as many days on medication as compared to children without ASD, which is particularly noteworthy as there is no FDA-approved medication to cure the behavioral and social deficits of ASD; 20% of children with ASD experienced one or more seizures between the ages of 2-18 as compared to 4% of children without ASD; 30% of children with ASD had sleep disorders that require treatment.
The research team was able to examine the records of more than 8,000 children starting from birth, and even before birth by studying their motherâ€™s medical records during pregnancy. The large data set allowed the researchers to explore the impact of more than 50 potential risk factors at one time. Infants with seizures in the first 90 days of life were seven times more likely to be diagnosed with ASD. In the perinatal period, birth asphyxia, preterm birth, low birth weight, newborn infections, and newborn complications were also associated with increased risk of ASD. A number of maternal medical conditions were associated with eventual diagnosis of ASD including high blood pressure, asthma, mental health problems, and obesity. The use of assisted fertility treatments and procedures and labor and pregnancy complications were also associated with increased risk of ASD. Finally, the use of medications during pregnancy was also associated with ASD. These included exposure to antibiotics, antivirals, asthma medications, muscle relaxants, cardiac medicine, anticonvulsants, mental health medications, anti-vomiting medications, diabetes medications, and fertility drugs.