Autism Spectrum Disorder Linked to Increased Risk of Substance Abuse
A new large-scale study has revealed that people with autism spectrum disorder (ASD) are at an increased risk for substance abuse disorders and related problems – contrary to what clinicians have historically believed.
For the study, researchers from Poland and Sweden examined data tallied between 1973 and 2009 from Swedish population registers. They identified nearly 27,000 people diagnosed with autism spectrum disorders and over 96,000 relatives. Persons with autism spectrum disorder were matched by sex, country, and birth year to a sample of nearly 1.34 million people without the disorder.
The two groups were compared, and researchers found that over 3% of people with autism spectrum disorders had also been diagnosed with a substance abuse disorder in the past – versus less than 1% of the control population sample.The highest risk was related to illicit drugs, followed by alcohol and tobacco.
However, mentally disabled patients with ASD were not associated with an increased risk of substance abuse. It was among those who were not mentally disabled and had ASD that development of a substance use disorder was more likely than others.
Patients diagnosed co-morbidly with ASD and ADHD (attention deficit hyperactivity disorder) were the most vulnerable to substance addiction. Researchers noted that persons with ASD might be more susceptible to substance abuse disorder because they “may find helpful to reduce tension and enhance social skills.”
Interesting enough, the study also revealed that the relatives of persons with ASD were also at increased risk of developing an addiction to substances. That is, researchers found that parents and siblings of ASD patients exhibited the highest risk of developing a substance abuse disorder.
Also, parents and full siblings (as opposed to half) had a much higher chance of dying of an overdose:
“Family data suggested shared liability between ASD and substance use disorders between relatives.”
Researchers believe that this liability may be explained in one or more of three ways:
- There may be shared genetic risk factors between addiction and autism
- Parental substance use may increase gene mutations associated with autism
- The association between autism and addiction could be related to environmental factors
Indeed, genetic mutations appear to explain why relatives of autistic persons are at a heightened risk for addiction. A recent medical review issued by the Department of Neuroscience at the University of Minnesota stressed the shared similarities between addiction and autism.
According to this review, there are commonalities between neurological systems and the molecules that regulate behavioral and biological responses to addiction and the development of autism:
“It is quite likely that some common elements of this circuitry…contribute to the pathophysiology of both ASDs and addiction, while other elements…are uniquely involved in only one disorder.”
This study stressed that clinicians have been under the assumption that substance addictions happen only sporadically in people with ASD, yet no evidence has been gathered from scientific studies to imply this is true.
Rather, this impression may be derived from the autism symptom that manifests in the engagement of repetitive behaviors and adherence to established rules, which could make people with autism appear less likely to use drugs or break the law.
About Autism Spectrum Disorders
Autism spectrum disorder is the name for a group of developmental disorders that includes a wide range of symptoms, skills, and levels of disability.
People with ASD typically have the following characteristics:
- Ongoing social issues, including communication difficulties and interpersonal interaction
- Repetitive behaviors
- Limited interests or activities
- Symptoms are usually recognized by around age two
- Symptoms impair the person’s ability to function socially, academically, hold a job, or other areas of life
- People may have impairments that range from mild to severe
People with autism may have other problems, including sensitivity to light, noise, clothing, or temperature. They may also experience sleep disturbances, digestion problems, and irritability.
People with ASD are also unique, as it is common for them also to exhibit strengths and abilities uncommon to others.
Strengths and abilities may include:
- Above-average intelligence (may be nearly 50%)
- Ability to learn things in detail and recall information for long periods of time
- Strong visual and auditory skills
- Above-average proficiency in math, science, music, or art.
Last year, the Centers for Disease Control and Prevention reported that 1-in-68 school-aged children in the U.S. were affected by ASD.
A study published last month revealed that although ASD diagnoses are increasing, the number of patients who are seriously struggling with the condition has decreased significantly since the turn of the century.
In 2000, 16% of patients with autism had at least three symptoms rates as extreme, versus less than 2% by 2006. Also, the number of people with ASD who did not exhibit extreme symptoms rose from 58.5% to 86.6% during the same period.
According to study authors:
“…a shift toward diagnosing individuals with less severe behavioral symptoms may have contributed to the increasing prevalence of ASD diagnoses.”