Introduction
Communication and social impairments displayed by individuals with Asperger's disorder (AD) pose unique challenges to speech-language pathologists who oftentimes traverse unchartered territory in hopes of finding the most efficacious treatments to remediate these deficits. Asperger's disorder (AD), also called Asperger's syndrome, is a neurobiological condition on the autism spectrum and, according to Baron-Cohen (2005) is thought to affect approximately 75% of individuals diagnosed with an autism spectrum disorder. Although AD is considered to be the mildest expression of autism, there are many complex factors that come into play as speech-language pathologists seek an appropriate course of treatment for this condition. This article deals with one of these challenges, the presence of co-occurring psychiatric disorders.
It has been estimated, but not confirmed, that approximately 40% of individuals referred for an autism spectrum disorder (ASD) evaluation, a group which includes a high proportion of individuals with AD, also evidenced some symptoms of a psychiatric disorder (Munesue, Ono, Mutoh, Shimoda, & Nakatani, 2008). Proper assessment and treatment of AD can be problematic because of an "overlap" in symptomatology with other psychiatric disorders. For example, restricted interests and obsessive behaviors are hallmarks of AD, but they are also key behaviors noted in obsessive-compulsive disorder. This article deals with the importance of recognizing the comorbidity (i.e., co-occurrence) of AD with other disorders and the effect comorbidity has on intervention and treatment outcomes. The coexistence of AD and bipolar disorder (BD) will be highlighted since an increase in the comorbidity of these two conditions has been noted in recent years (Gutkovich, Carlson, Carlson, Coffey, & Wieland 2007).
Prevalence of ASD
The prevalence of ASD has greatly increased in recent years and is now considered by the Centers for Disease Control (CDC) to be a major public health concern. Alarmingly, a CDC report published in December (2009) found that the occurrence of ASD increased 57% between 2002 and 2006. These new prevalence statistics translate to 1 in 110 eight-year-olds across 10 research sites having been identified as having an ASD. Although many factors play a part in this disquieting increase in autism, such as better diagnosis, the identification and increased awareness of AD has contributed considerably to this expansion. However, despite improved and more available diagnostic mechanisms and the inclusion of milder forms of autism on the spectrum (i.e., AD), the CDC has not ruled-out the possibility that children are now simply at a greater risk of having an ASD. Due to the rise of AD, speech-language pathologists have seen a marked increase in the number of individuals with this condition represented on clinic caseloads. Now more than ever, finding treatments to remediate this disorder is of utmost importance to assure that these individuals lead fulfilling and productive lives.
Diagnostic Criteria for AD
Asperger's disorder was originally described by Hans Asperger, an Austrian pediatrician, in 1944. Dr. Asperger's work went largely unnoticed until Lorna Wing (1981) translated his writings for an English-speaking audience. From the time Hans Asperger first described four boys who lacked empathy and an ability to form friendships, a condition he termed autistic psychopathy, a number of researchers (Wing, 1981; Myles & Simpson, 2001) have added to the understanding of this condition. Pedantic speech, awkward gross motor movements, obsession with certain topics, and lack of empathy are behaviors commonly reported to be indicative of AD (Wing, 1981). The inability to conform to social norms and societal expectations appears to be the most salient clinical characteristic of individuals with AD. Children with typical development learn these social skills incidentally and do not require direct teaching to pick-up on specific social cues. This is not true for children with AD.
The fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; American Psychiatric Association, 1994) was the first edition to include AD. The manual listed a set of six criteria that must be present for a diagnosis of AD. These criteria include:
- "Impairments in social interaction;
- Restricted repetitive and stereotyped patterns of behaviors, interests, or activities;
- Disturbances causing clinically significant impairments in social, occupational, or other areas of functioning;
- No clinically significant general delay in language;
