Teasing Apart Psychiatric Misdiagnoses From Comorbidity and Implications for Psychotropic Medication Use In Adolescents with High-Functioning ASDs

Background:  

Clinical anecdotes suggest that high-functioning individuals with ASD often first receive psychiatric misdiagnoses, which may interfere with the correct identification of their ASD. This problem is further complicated by high rates of psychiatric comorbidity in ASD and difficulty differentiating when a true comorbid disorder is present. The medication implications of many psychiatric disorders underscores the importance of better understanding diagnostic practices.

Objectives:  

This study’s overall goal was to highlight the complexity inherent in the proper diagnosis of higher-functioning individuals with ASD, particularly related to characterizing their emotional and behavioral dysregulation. Two specific aims were: 1) To document the lack of concordance between lifetime history of community-based psychiatric diagnoses among children with high-functioning ASD and their “true” psychiatric comorbidity history established via a structured psychiatric interview modified for ASD; and 2) To investigate the relationship between community psychiatric diagnosis patterns and psychotropic medication use.

Methods:  

Participants included 35 10 – 17 year old children with an ASD (confirmed with the ADOS and ADI) and without mental retardation. Lifetime comorbid psychiatric diagnoses were established via the Autism Comorbidity Interview (ACI). These “gold-standard” diagnoses were compared to parent report of prior psychiatric diagnoses that the participant had received in the community. The relationship between prior diagnoses and number of psychotropic medications attempted was determined.

Results:  

ADHD, anxiety disorders, and depressive disorders were the three most common diagnoses for both prior community diagnoses and based on the ACI (though in different orders and magnitudes). Especially for prior community diagnoses, rates of diagnoses in this sample were higher then national prevalence rates for U.S. adolescents; for example 14.3% (n = 5) had received a bipolar disorder diagnosis at some point in their lives, compared to a national lifetime average for adolescents of 2.6% (Merikangas et al., 2010). Although there was significant psychiatric comorbidity in this sample, the mean number of prior community psychiatric diagnoses (2.15, SD = 1.88; range 0-7) was significantly higher then the mean number of lifetime psychiatric disorder diagnoses supported by the ACI (0.88; SD = 2.2; range 0-4), p < .001. The vast majority of prior diagnoses were false positives in comparison to the ACI results. The number of prior psychiatric diagnoses was significantly correlated with the number of psychotropic medications attempted, r (35) = .781, p < .001. Medication use was high overall, and especially pronounced among participants who had been previously diagnosed with bipolar disorder or oppositional defiant disorder, yet most of these diagnoses were not supported on the ACI.

Conclusions:  

Many participants received incorrect prior psychiatric diagnoses, which could delay or interfere with the proper identification of their ASD. Although a substantial number of children met ACI criteria for comorbid psychiatric disorders, there was also a high rate of previous false positive psychiatric diagnoses. The strong relationship between prior community psychiatric diagnoses and psychotropic medication use highlights the importance of increasing awareness and understanding of high-functioning ASDs (including the associated emotional and behavioral dysregulation) in general psychiatric clinics in order to promote faster identification and appropriate treatments.