New autism definition may decrease diagnosis by one-third, Columbia University finds
New diagnosis guidelines for autism spectrum disorder (ASD) issued by the American Psychiatric Association (APA) may reduce by almost one third the total number of people being diagnosed, according to new research from Columbia University School of Nursing published in the Journal of Autism and Developmental Disorders. The guidelines, released in May 2013 and the first major update to psychiatric diagnosis criteria in almost two decades, may leave thousands of developmentally delayed children each year without the ASD diagnosis they need to qualify for social services, medical benefits and educational support.
A team led by Kristine M. Kulage, MA, MPH, director of the Office of Scholarship and Research Development at Columbia Nursing, conducted a systematic literature review and meta-analysis to determine the effect of changes to the Diagnostic and Statistical Manual of Mental Disorders (DSM), the APA’s classification tool for psychiatric conditions, on diagnosis of individuals with ASD. The study found a statistically significant decrease in ASD diagnosis of 31 percent using the new manual, DSM-5, compared with the number of cases of ASD that would have been identified under the previous version of the manual, DSM-IV-TR.
“This study raises a concern that a medical provider diagnosing a child under the new guidelines won’t find the child to be on the autism spectrum, when the same child under the old criteria might have been diagnosed with ASD,” says Kulage.
The old manual, DSM-IV-TR, included three distinct subgroups under the broad definition of ASD: autistic disorder (AD), Asperger’s disorder, and pervasive development disorder-not otherwise specified (PDD-NOS). The revised manual, DSM-5, eliminates these subgroups, instead establishing a more limited range of criteria for a diagnosis of ASD that is designed to encompass individuals who previously would have fallen into one of the subgroups. The DSM-5 also added a new category called social communication disorder (SCD) to diagnose individuals who have verbal and nonverbal communication impairments but lack other attributes associated with autism. Some individuals diagnosed with PDD-NOS under the old manual would be identified as individuals with SCD under DSM-5, according to the APA.
DSM - 5: The New Criteria
Concerns about ASD in DSM - 5
• Sensitivity has been “sacrificed” in order to improve specificity
– Social communication domain
– Restrictive interests and repetitive behaviors domain
• Merging Asperger disorder (and PDD - NOS) into autism spectrum disorder results in loss of identity
and ignores uniqueness of Asperger dx
• Pre - /post DSM - 5 research studies will not be comparable
• Changes in criteria threaten services delivery
Under DSM-5, there was a statistically significant decrease in AD diagnosis of 22 percent, compared with the fourth edition of the manual, the meta-analysis found. There was also a statistically significant decrease of 70 percent in diagnosis of PDD-NOS. While diagnosis of Asperger’s also declined under DSM-5, the reduction was not statistically significant. In addition, the study found that some individuals who no longer met the criteria for an ASD diagnosis under DSM-5 would also fail to meet the criteria for SCD.
“We are potentially going to lose diagnosis and treatment for some of the most vulnerable kids who have developmental delays,” says Kulage. “In many instances, children require a diagnosis of ASD to receive medical benefits, educational support and social services.”
Approximately 1 in 88 children in the U.S. have ASD, according to the Centers for Disease Control and Prevention. People with ASD tend to have difficulties with communication, misread nonverbal interactions, and have difficulty making friends. They may also be heavily reliant on routines, extremely sensitive to changes in their environment, and intensely focused on interests not appropriate to the social context they are in. Symptoms fall on a continuum, with variation in severity, and early diagnosis and access to treatment have been proven to result in better outcomes.
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The paper is titled: “How Will DSM-5 Affect Autism Diagnosis? A Systematic Literature Review and Meta-analysis” and it appeared in the February 2014 issue of the Journal of Autism and Developmental Disorders. Other contributors are: from Columbia Nursing, Arlene Smaldone, PhD, CPNP, associate professor and assistant dean, scholarship and research, and Elizabeth Cohn, PhD, RN, assistant professor and Robert Wood Johnson Foundation Nurse Faculty Scholar. Kulage completed the research while enrolled in a master’s degree program at Joseph P. Mailman School of Public Health.
Diagnosis and Evaluation for Autism Spectrum Disorders
American Academy of Neurology and the Child Neurology Society
Clinical Practice Recommendations:
Genetic testing in children with autism, specifically high-resolution chromosome studies (karyotype) and DNA analysis for Fragile X, should be performed in the presence of intellectual disability (or if intellectual disability cannot be excluded), if there is a family history of Fragile X or undiagnosed intellectual disability, or if dysmorphic features are present. However, there is little likelihood of positive karyotype or Fragile X testing in the presence of high-functioning autism.
Selective metabolic testing should be initiated by the presence of suggestive clinical and physical findings such as the following: evidence of lethargy, cyclic vomiting, or early seizures; presence of dysmorphic or coarse features; evidence of intellectual disability cannot be ruled out; or if occurrence or adequacy of newborn screening is questionable.
There is inadequate evidence to recommend an electroencephalogram study in all individuals with autism. Indications for an adequate sleep-deprived electroencephalogram with appropriate sampling of slow wave sleep include clinical seizures or suspicion of subclinical seizures and a history of regression (clinically significant loss of social and communicative function) at any age, but especially in toddlers and preschoolers.
Recording of event-related potentials and magnetoencephalography are research tools at the present time, without evidence of routine clinical utility.
There is no clinical evidence to support the role of routine clinical neuroimaging in the diagnostic evaluation of autism, even in the presence of megalencephaly.
There is inadequate supporting evidence for hair analysis, celiac antibodies, allergy testing (particularly food allergies for gluten, casein, Candida, and other molds), immunologic or neurochemical abnormalities, micronutrients such as vitamin levels, intestinal permeability studies, stool analysis, urinary peptides, mitochondrial disorders (including lactate and pyruvate), thyroid function tests, or erythrocyte glutathione peroxidase studies.
The authors declare no financial or other conflicts of interest.
Columbia University School of Nursing is part of the Columbia University Medical Center, which also includes the College of Physicians & Surgeons, the Mailman School of Public Health, and the College of Dental Medicine. With close to 100 full-time faculty and 600 students, the School of Nursing is dedicated to educating the next generation of nurse leaders in education, research, and clinical care. The School has pioneered advanced practice nursing curricula and continues to define the role of nursing and nursing research through its PhD program which prepares nurse scientists, and its Doctor of Nursing Practice (DNP), the first clinical practice doctorate in the nation. Among the clinical practice areas shaped by the School’s research are the reduction of infectious disease and the use of health care informatics to improve health and health care.
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