What Disorders Are Related to Autism?

Research suggests it’s common to experience a secondary mental health issue if you’re autistic. You’re also more likely to have another mental health condition compared to someone who’s nonautistic.

You could be more likely to experience:

• anxiety
• depression
• bipolar disorder
• eating disorders
• obsessive-compulsive disorder (OCD)

Sometimes, these mental health conditions can develop based on how your communication and behavior patterns affect your day-to-day life.

Anxiety

Some research says that about 50% of autistic people live with anxiety.

If you’re autistic, you might experience anxiety as:

• persistent worry
• social phobia
• separation anxiety
• other phobias (for instance, of loud noises or spiders)

Autistic people may find it especially tricky to self-soothe once their anxiety is triggered — even if they don’t have a specific anxiety disorder.

Depression

A 2018 literature review found that 37% of autistic people had been diagnosed with a depressive disorder at some point in their life.

Other research reports that autistic people are 4 times more likely to experience depression than nonautistic people.

If you’re on the spectrum, depression may look more like insomnia or restlessness rather than sadness. Autistic people with depression also have a higher risk of experiencing suicidal thoughts and dying by suicide than the general population.

Past bullying and feelings of loneliness can also contribute to depression for some. Pinpointing depression early can help you access the right support and help you tackle any depression symptoms that are weighing you down.

Bipolar disorder

It’s not uncommon for autistic people to live with bipolar disorder, and it’s also more likely that they’ll experience it than the general population.

There are a few types of bipolar disorder, including bipolar I and II disorders and cyclothymic disorder. Bipolar disorders cause shifts in mood which can include mania, hypomania (mild mania), and depression.

Bipolar disorder may also cause psychosis, including hallucinations and delusions. This is sometimes misidentified as schizophrenia.

When it comes to treating bipolar disorder, autistic people may find a treatment approach that’s specific to them the most helpful.

Eating disorders

Research suggests a link between autism and eating disorders. In particular, autistic women may be more likely to develop an eating disorder than autistic men.

Multiple studies have found connections between autism and anorexia, and research suggests up to 30% of people with anorexia are also autistic or have autistic traits.

Avoidant/restrictive food intake disorder (ARFID) is another common eating disorder in autistic people. ARFID can cause difficulties eating certain foods and may lead to malnutrition. For autistic people, ARFID could be closely tied to sensory issues with different types of food.

Because autistic people may respond differently to the “status quo” eating disorder treatments, clinicians are working to create treatment plans that can better support the needs of autistic people with eating disorders.

Obsessive-compulsive disorder (OCD)

In one recent study, 5% of autistic young people were found to have OCD. When autism and OCD occur together, they could have a greater impact on a person’s social skills than when they occur on their own.

There’s also some evidence suggesting that many people with OCD may be living with undiagnosed autism.

Since autism and OCD have some overlapping behavior patterns — like strongly preferring certain rituals — it can be hard to tell where one ends and the other begins.

OCD can look like:

• the need to do things a certain way
• repetitive behaviors or rituals
• anxiety
• recurring and persistent thoughts

In one study, OCD was also found to cause higher levels of hoarding behavior in autistic people.

Some medical conditions show up more often in autistic people than in the general population.

The following medical conditions tend to be more common for autistic people:

• sleep disorders
• seizure disorders
• gastrointestinal issues

In one literature review, medical conditions were found in anywhere from 10–77% of autistic people.

Sleep disorders

An estimated 13% of autistic people live with sleep disorders and experience symptoms like:

• difficulty falling asleep
• waking up repeatedly in the night
• prolonged nighttime awakenings
• waking very early in the morning

Research suggests that sleep problems like insomnia affect as many as 2 out of 3 autistic children.

Many autistic people have other conditions which can also impact or disrupt sleep, like:

• gastrointestinal problems
• ADHD
• anxiety

People with these other conditions may also take medications that affect sleep. For example, many people with ADHD take stimulant meds, which can cause insomnia. And cramps from medication-induced constipation could also keep you up at night.

Seizure disorders

A seizure disorder, or epilepsy, is a brain disorder marked by recurring seizures (aka convulsions).

Research suggests epilepsy is more common in autistic people than among the general population and may impact about 12% of autistic people.

One additional risk factor for epilepsy in autistic people is having an intellectual disability. Autistic women may also be more likely to experience seizures than autistic men.

Compared to those without seizures, autistic children who experience seizures may also be more likely to have sleep difficulties and behavior problems.

Diagnosing and getting the right treatment for epilepsy is important, since untreated epilepsy can put you at risk for other health issues.

Gastrointestinal (GI) issues

GI issues like constipation and diarrhea are a common symptom for many autistic people. A literature review found that on average, 46% of autistic people experienced GI symptoms.

Constipation may co-occur with autism because it’s:

• a side effect of taking certain medications
• caused by sensory or behavioral issues related to autism
• caused by ARFID or another eating disorder
• caused by a sluggish intestinal tract
• being caused by issues related to metabolism
• happening due to differences in anatomy or gut microbiota

In many cases, constipation in autistic people happens due to a combo of these factors.

GI symptoms can also play a role in behavioral patterns like hyperactivity, aggression, and self-harm. These behavior patterns can be a sign that GI symptoms are causing pain or discomfort, especially in the case of autistic people who are less verbal.

Diarrhea can be another potential issue, caused by:

• lactose intolerance
• food allergies
• celiac disease

GI symptoms are typically treated with dietary restrictions. Other times, medications or sometimes surgery could help.

Certain genetic conditions are often linked to autism spectrum disorder. Fragile X syndrome and tuberous sclerosis are two examples.

Genetic conditions cause their own set of symptoms, but they can also intensify some communication and behavioral patterns tied to autism.

Fragile X syndrome (FXS)

While ASD is a behavioral diagnosis, FXS is a genetic diagnosis. When associated with FXS, ASD is caused by mutation in the fragile X gene.

Fragile X syndrome causes:

• intellectual disability
• delayed development
• specific behavior patterns such as hyperactivity

In fact, FXS is considered the leading genetic cause of ASD. And according the Centers for Disease Control and Prevention, 46% of boys and 16% of girls with FXS were also autistic.

Since the link between FXS and autism is pretty well-known, many clinicians recommend genetic testing for autistic children to screen for FXS and other genetic conditions.

Tuberous sclerosis

Tuberous sclerosis is a rare genetic condition that causes noncancerous tumors to grow on the body’s vital organs. Research suggests that around 50% of people with tuberous sclerosis meet the diagnostic criteria for ASD.

Depending on where these tumors develop, they can cause:

• seizures
• intellectual impairment
• skin issues
• kidney disease
• headaches
• blurry vision
• behavioral symptoms like aggression or self-harm
• trouble breathing

Tuberous sclerosis can occur alongside autism, but it could also play a role in causing autism.

In addition, autistic people may find that their tuberous sclerosis symptoms feed into some of their autism-related behavior patterns. This usually happens when tumors grow in the brain or cause physical pain.

Neurodevelopmental disorders impact brain function and are usually diagnosed in childhood. Autism is a neurodevelopmental disorder.

Some common neurodevelopmental disorders associated with autism include attention deficit hyperactivity disorder (ADHD) and intellectual disability.

Since ASD and other neurodevelopmental disorders all begin to show up around the same time, it’s very common for a child who’s been diagnosed with autism to also meet the criteria for another neurodevelopmental disorder.

In fact, over 50% of autistic children may have a co-occurring neurodevelopmental condition.

Attention deficit hyperactivity disorder (ADHD)

Autistic children with ADHD tend to have challenges with executive functioning — how your brain is able to process planning, self-control, short-term memory, and decision-making.

ASD and ADHD can occur together, and genetics tend to play a role in both conditions. They also have similar symptoms, including:

• social difficulties
• trouble settling down
• limited ability to focus on things outside of interest areas
• impulsivity

Young children with both conditions may also be more likely to experience:

• tantrums
• trouble making friends
• challenges at school

Some research suggests that anywhere from 30–80% of autistic people might be living with ADHD.

Intellectual disability

There’s a lot of overlap between intellectual disability and autism diagnoses, but they’re two very different conditions.

Research reports that while at one point it was thought that 70% of autistic people had an intellectual disability, it’s actually probably closer to 30%.

Intellectual disabilities can impact reasoning, planning, and abstract thinking. And since both autism and intellectual disabilities can impact communication, it’s not always clear right away which diagnosis is a better fit — or if both apply.

According to the DSM-5, autism shouldn’t be diagnosed if it can be better explained as an intellectual disability.

If you’re autistic, the chances of having certain secondary conditions is higher. These conditions can involve mental or physical health, genes, or development.

If you think your child might be autistic or have another condition, consider bringing your concerns to their pediatrician. Most pediatricians are knowledgeable about signs of developmental differences and can help you move forward with a diagnosis and support plan.

If you’re autistic and think you could have another condition, it’s always OK to bring it up with a doctor or someone else you trust. From there, you can create a plan to manage the symptoms of that condition.

Finding out if you have another condition that overlaps with autism isn’t always simple. Many of these conditions are interwoven in a complex tangle of cause-and-effect loops.

Still, identifying and understanding your symptoms can help put you back in the driver’s seat of your well-being.