A Wrinkle in Time: From Early Signs to a Diagnosis of Autism

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In the last decade, worldwide epidemiological studies of autism spectrum disorders (ASDs, used here as a synonym of pervasive developmental disorders) have consistently yielded estimates of prevalence ranging from 5 to 10/1,000. Catching up with other countries with more established traditions of psychiatric epidemiology, the vigorous efforts pursued by the Centers for Disease Control and Prevention in the United States since 1996 have recently confirmed that at least one child in 150 was impaired with a broadly defined ASD. Autism spectrum disorders have become one of the most common severe childhood disorders, with huge personal, familial, and societal associated burden. Using the Centers for Disease Control and Prevention survey data on a large sample of 8-year old U.S. children born in 1994, the study by Shattuck et al. in this issue of the Journal examines a critical time point in the developmental trajectory of children diagnosed with ASD, that of diagnosis or identification. Although age at diagnosis has no intrinsic biological significance, this time variable often represents a turning point for children with ASD and their parents. As an end point, the confirmation of an ASD diagnosis provides coherence and meaning after several months, and more often years, of atypical developmental patterns that worried parents have been witnessing in their young child. In most studies, the first parental concerns emerge between 15 and 24 months of age, usually because of failure in the development of social and communication skills. Although the parent’s experience is highly consistent with the long established diagnostic criterion of evidence of symptoms before age 3 years for the diagnosis of autism, a prolonged delay occurs between parental recognition of first symptoms and the diagnostic confirmation. In many countries, the age at diagnosis has, on average, decreased during the last two decades from age 5 to 6 years to age 3 years or even less. Because access to services is contingent on receipt of a formal diagnosis, a late diagnosis means that precious time is lost for these children and unnecessary stress imposed on their parents. The finding of a median age of 5.7 years in the 1994 U.S. birth cohort points to immediate needs to improve early detection and diagnosis of ASD in the United States. Knowledge of factors that mitigate timing of identification of an ASD condition is important to achieve that goal. There were huge geographical disparities in the United States for the time of identification. The median time of identification was the most delayed for children from Alabama, the state where the lowest prevalence was also reported, which suggests that both global underdetection and later identification co-occur in areas where awareness and services are lagging behind. Other factors such as lower educational level and younger age of the mother, or in some instances, the mother’s ethnic background, are associated with further delays in diagnosis timing. In the absence of variation in incidence of ASD for such social indices, the findings by Shattuck et al. point toward potential sources of social differences in the public handling of ASDs. The unspoken story of social inequalities in ASD extends beyond the timing of diagnosis. In many countries, wealthier and more educated parents can provide their toddlers with earlier, privately funded, and more intensive interventions, given that limited availability and long waiting times for appropriate public services can be discouraging. Social factors, including the ability of parents to engage as treatment partners and learn the techniques that matter, have been neglected by a generation of autism professionals that, rightly, wanted to turn away from the hideous unvalidated theories of ‘‘refrigerator mothers.’’ With new studies showing the role of parents as critical mediators of treatment response or outcome, autism professionals should look again at the role of family characteristics and of broader social variables that may act as barriers or promoters of treatment access and outcome. However, is it so important to identify ASD at an earlier age? The answer is unequivocally ‘‘yes’’ but with nuances. Two decades ago, a formidable change occurred in families’ hopes Accepted January 22, 2009. Dr. Fombonne is with the McGill University and the Montreal Children’s Hospital. Correspondence to Dr. Eric Fombonne, Department of Psychiatry, Montreal Children’s Hospital, McGill University, 4018 Ste-Catherine West, Montreal, Quebec, H37 1P2, Canada; e-mail: eric.fombonne@mcgill.ca. 0890-8567/09/4805-0463 2009 by the American Academy of Child and Adolescent Psychiatry. DOI: 10.1097/CHI.0b013e31819e40c0 E D I T O R I A L