Clinical Review

Autism: Why the rise in rates?

Clinician Reviews. 2014 June;24(6):316-320

References

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Autism comorbidity. As autism is frequently comorbid with other developmental disabilities, advances in medical technology that have led to a decline in neonatal death and overall mortality among the disabled may mean more survivors are subsequently diagnosed with an autism comorbidity.

Biological factors. Recent studies suggest that advanced paternal age can increase the risk of autism.³⁹ Twin studies suggest moderate genetic heritability, along with a substantial environmental contribution to the development of autism.⁴⁰ And new research suggests that maternal stressors during pregnancy—eg, trauma, illness, or substance abuse—may increase a child’s risk of developing autism, among other psychiatric disorders.⁴¹

The important role you play in the diagnosis of autism

It is clear that autism is more common than previously thought³ and that various factors are at work. Ensuring that children are promptly and properly evaluated begins when primary care physicians take parents’ concerns seriously and keep an eye out for common symptoms and characteristic developmental delays that may be evident even in the first year of life.

If symptoms are not severe enough to be detected in the child’s first several years, the next likely presentation will be when a parent gets a call from school suggesting that their child be tested for autism. While this delayed presentation suggests a higher level of functioning, a full evaluation, including the use of questionnaires such as the Social Responsiveness Scale⁴² and ASSQ,²⁸ and appropriate referrals are still vital.

Puberty is another time when characteristics suggestive of autism that escaped earlier detection may be noted, and vague behavioral issues or concerns about intellectual impairment may become sufficiently troublesome to prompt a thorough evaluation. While behavioral therapy can be very helpful in such cases, medical therapy directed at co-occurring conditions (ie, a mood or anxiety disorder, including obsessive-compulsive disorder) may also provide significant benefit.

Puberty is another time when characteristics suggestive of autism that escaped earlier detection may be noted. Whatever the age of the child, his or her parents should be counseled as to the general nature of autism, reassured of the availability of treatment options and given the appropriate referrals, and encouraged to learn more by availing themselves of resources (TABLE) and support groups. A consumer update from the US Food and Drug Administration titled “Beware of false or misleading claims for treating autism” (http://www.fda.gov/ForConsumers/ConsumerUpdates/ucm394757.htm) will be helpful for many parents, as well.

CORRESPONDENCE
Robert G. Zylstra, EdD, LCSW, Department of Family Medicine, The University of Tennessee College of Medicine, 110 East Third Street, Chattanooga, TN 37403; robert.zylstra@erlanger.org