Conditions comorbid to autism
There are many comorbid disorders associated with autism spectrum disorders and Asperger's Syndrome.
The major comorbid disorders associated with autism and Asperger's include post-traumatic stress disorder, sensory integration disorder, anxiety disorder, panic disorder, social anxiety disorder, attention deficit hyperactivity disorder (ADHD), obsessive-compulsive disorder (OCD), seizures, Tourette's syndrome, and depression. At at the lower functionioning end of the spectrum, Mental Retardation is commonly sited, often alongside Fragile X Syndrome, the most common genetic cause of mental retardation. Tuberous Scelerosis is mentioned here because it is more commen among autistics, see below however, it is very rare.
Depression/Anxiety Problems
Depression and its cousin, anxiety, may be the most common comorbid disorders accompanying autism, affecting over half of all people with Asperger's. People with AS attempt suicide at a staggeringly high rate in comparison to the general population, although whether this is due to AS itself or to depression comorbid to AS, is a matter of debate.
Hyperactivity/Attention abnormalitys
Attention-deficit hyperactivity disorder (ADHD) is one of the most commonly diagnosed and controversial mental disorders among children, and is increasingly recognized as afflicting adults as well. Its symptoms include inattention, hyperactivity, and impulsivity. According to sources such as the CDC, the causes are currently unknown, and it is thought that the term covers a variety of related disorders. There is no single medical test that can accurately diagnose ADHD, though there are assessment tools.
The authoritative definition of ADHD is to be found in the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders-IV (Text Revision) (DSM-IV-TR), which also defines three subtypes of ADHD:
- Predominantly Inattentive
- Predominantly Hyperactive-Impulsive
- Combined Type
According to some recent studies, ADHD is an inheritable dysfunction of dopamine metabolism mainly in the frontostriatal region of the human brain. New studies consider the possibility that norepinephrine metabolism also affects this disorder (see Krause, Dresel, Krause in Psycho 26/2000 p.199ff). One should note that almost all of the latest studies have been sponsored by drug companies.
Obsessive-Compulsive Disorder
The essential feature of this disorder is recurrent obsessional thoughts or compulsive acts. Obsessional thoughts are ideas, images or impulses that enter the individual's mind again and again in a stereotyped form. They are almost invariably distressing (because they are violent or obscene, or simply because they are perceived as senseless) and the sufferer often tries, unsuccessfully, to resist them. They are, however, recognized as the individual's own thoughts, even though they are involuntary and often repugnant. Compulsive acts or rituals are stereotyped behaviours that are repeated again and again. They are not inherently enjoyable, nor do they result in the completion of inherently useful tasks. It must be recognized that this is different from the obsessions that are a feature of autistic spectrum disorders in that the obsessions are not enjoyable or in any way beneficial, which can sometimes be the case with autism, for instance an obsession to study an interest.
Seizures
One in four autistic children develops seizures, often starting either in early childhood or adolescence. Seizures, caused by abnormal electrical activity in the brain, can produce a temporary loss of consciousness (a "blackout"), a body convulsion, unusual movements, or staring spells. Sometimes a contributing factor is a lack of sleep or a high fever. An EEG can help confirm the seizure's presence.
In most cases, seizures can be controlled by a number of medicines called anticonvulsants. The dosage of the medication should be adjusted carefully so that the least possible amount of medication will be used to be effective.
Sensory problems
When children's perceptions are not hyperacute, they can process and learn from sensory input. On the other hand, if sensory information is faulty, the child's experiences of the world can be confusing. Many autistic children are highly attuned or even painfully sensitive to certain sounds, textures, tastes, and smells. Some children find the feel of clothes touching their skin almost unbearable. Some sounds—a vacuum cleaner, a ringing telephone, a sudden storm, even the sound of waves lapping the shoreline—will cause these children to cover their ears and scream.
In autism, the brain seems unable to balance the senses appropriately. Some autistic children are oblivious to extreme cold or pain. An autistic child may fall and break an arm, yet never cry. Another may bash his head against a wall and not wince, but a light touch may make the child scream with alarm. The brain seems to not be able to screen out unimportant stimuli while admitting what is important, so the autistic may have to deal with overwhelming amounts of sensory input day and night. The child who doesn't cry may feel pain, but his brain may not connect the pain to the need for making sounds.
Autistic babies are often observed to stiffen when held. This is due to the sensory overload discussed above, and the stiffening is a coping mechanism which also occurs in adults. Because sensory overload occurs from birth, the coping behaviour is notable as one of the earliest observable symptoms of autism. However, it is not universal among autistics. There is great variation in the susceptibility to sensory overload.
Mental retardation
Many autistic children have some degree of mental impairment. When tested, some areas of ability may be normal or superior, while others may be especially weak. For example, an autistic child may do well on the parts of the test that measure visual skills but earn low scores on the language subtests.
Mental retardation isn't a mandatory feature of autism. In fact, most people with autism have at least "normal" results on intelligence test. Some are Mensa members. IQ test results are much more uneven in the sub-categories than normal, frequently showing a peak in visuo-spatial tasks or rote memory. Because of this an autistic may have much more skill in doing certain things than his IQ seems to indicate, and when taken to the extreme it is called being an autistic savant.
Fragile X syndrome
This disorder is the most common inherited form of mental retardation. It was so named because one part of the X chromosome has a defective piece that appears pinched and fragile when under a microscope. Fragile X syndrome affects about two to five percent of people with ASD. It is important to have an autistic checked for Fragile X, especially if the parents are considering having another child. For an unknown reason, if an autistic child also has Fragile X, there is a one-in-two chance that boys born to the same parents will have the syndrome. Other members of the family who may be contemplating having a child may also wish to be checked for the syndrome.
Tuberous Sclerosis
Tuberous sclerosis is a rare genetic disorder that causes benign tumors to grow in the brain as well as in other vital organs. It has a consistently strong association with the autistic spectrum. One to four percent of autistic people also have tuberous sclerosis.
Summary
If a comorbid disorder is present in an autistic, it often cannot be treated in the same manner as when it is present in neurotypicals. Many times the depression is caused more by society's attitudes and behaviors toward autistics than by the autism condition itself. This is called situational depression. Then there is seasonal affective disorder, which seems to be correlated with the amount of sunlight experienced by the person. This tends to be much worse in winter and mild in summer. Another type is dysthymia, which involves more a lack of joy in life than the intense brooding and misery found in clinical depression. The deep sadness called clinical depression may be present, and it may or may not respond to the usual medications.
For many types of mood, movement and sensory problems,it is genrally agreed that smaller amounts of medications work for persons with autism. Larger amounts just cause additional problems. The reason probably has to do with the structural neurology of autism -- if the difficulties are caused by structure and genetics, not by the typical "chemical imbalance," then chemicals won't affect them in the usual, accepted ways. Cognitive therapy can often help people deal with depressive states by changing the ways that they think about their situations and their thoughts.