Guidance for primary care clinicians to help distinguish fetal alcohol spectrum disorder (FASD) from autism spectrum disorder (ASD)
FASD refers to four groupings of fetal alcohol-related birth defects characterized by varying degrees of growth deficiency, specific dysmorphic features, and central nervous system dysfunction and malformation.
ASD is a neurodevelopmental disorder with core deficits in social communication and interaction and restrictive, repetitive patterns of behavior. The diagnosis is based on behaviors that vary depending on the patient’s age, cognitive level, and language skills.
The cause of FASD is alcohol exposure in utero, which has varying effects on the developing fetus. The cause of ASD is multifactorial, including genetic and environmental factors. Both disorders share some common behavioral characteristics, but each disorder’s overall symptom expression is unique.
Key Points
Dual diagnosis
A diagnosis of FASD does not preclude a diagnosis of ASD if the child meets criteria for both disorders. A small minority of children with FASD are also diagnosed with ASD, and treatment can be more complex due to the need to address (sometimes overlapping) problems with behavior and social interactions associated with both disorders.
Common characteristics
ASD and FASD may share characteristics, such as strong sensory interests and aversions, cognitive delays, and deficits in executive functioning and adaptive skills (Bishop, 2007). The patterns of symptom expression, however, are unique to each disorder.
Physical characteristics
Children with FASD often have a characteristic pattern of abnormal facial features, including a smooth philtrum, thin upper lip, and short palpebral fissures. It is not uncommon to also have low nasal bridge and micrognathia. There may be additional alcohol-related birth defects, including problems with the heart, kidneys, bones, or hearing. While ASD may have comorbid genetic conditions that have common associated physical characteristics, there are no physical findings that are as specific as in FASD.
Differences in social interactions
Children with ASD and FASD both struggle in social interactions but in different ways. While children with ASD often appear aloof and uninterested in social interactions, children with FASD tend to be not only interested in social interactions but also indiscriminately friendly with poor boundaries and no sense of “stranger danger.” Furthermore, when children with FASD do approach others or engage socially, they often lack the interpersonal skills necessary to move the interaction forward in a positive way. Such behaviors might include:
- Inappropriate statements or questions
- Difficulties with compromising, cooperating, or taking different roles with other children
- Difficulty with sharing
- Hyperactive or impulsive behavior that is difficult to manage from the standpoint of their interaction partner
Children with FASD struggle with social cues and often misunderstand or misinterpret facial expressions and eye gazes from other people. They also tend not to understand information conveyed by speech prosody (Stevens, 2013).
Nonverbal gestures
Children with FASD often can better use gestures and nonverbal communication to interact, demonstrate empathy, share enjoyment in social overtures, and use a greater range of facial expressions than children with ASD. Thus, “shared affect behaviors” have been shown to be relatively less impaired in FASD children when compared with ASD counterparts.
Cognitive functioning
ASD and FASD also differ in their characteristic patterns of cognitive disability. One study comparing ASD with FASD children found that 79% of ASD children had a higher nonverbal IQ compared to verbal IQ (Bishop et al., 2007). The opposite was true for children with FASD, with the majority demonstrating a higher verbal than nonverbal IQ.
Diagnosis
Diagnostic criteria for ASD and severity criteria are in the 5th edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5).
FASDs are diagnoses of exclusion and usually require a multidisciplinary evaluation to
ensure accurate diagnosis.
Incidence and Prevalence
FASD
It is estimated that FASDs affect 2-5% of live births in the US; FAS affects 2-7/1000 (May, 2009). The Centers for Disease Control and Prevention (CDC) estimates 1 case of FAS per 1000 live births, and at least 3 times as many are affected by FASD. FASD occurs in all socioeconomic and cultural groups.
Autism
About 1:54 children have been identified with ASD (Maenner, 2020). These estimates from the Autism and Developmental Disabilities Monitoring Network are based on data collected from health and special education records of children living in 11 communities across the United States during 2014.
Co-occurrence of FASD and ASD
Data on the association between FASD and ASD is limited. Prevalence data on both conditions is like an underrepresentation given that both disorders are underdiagnosed (Carpita et al., 2022). One systematic review found that the prevalence of ASD in children with FASD was 2.6%, which is almost twice the rate in the general population (Lange et al., 2018).
Management
Research has shown that children with FASD and ASD share similarities in social and communicative functioning, so behavioral interventions that address those areas would be helpful. Additional problems that can occur both in children with FASD and children with ASD include sleep disturbances and psychiatric conditions like ADHD. Management of comorbid conditions can help improve functional capabilities and quality of life for children with FASD and ASD
Role of Primary Care
- Prescribe medication or consult with a psychiatrist when indicated.
- Ensure referral to appropriate specialists to assist in diagnosis. The specialist may include a developmental pediatrician, neurologist, or psychiatrist.
- Recognize and address comorbidities, including sleep disorders, ADHD, mood disorders, inadequate nutrition or other growth concerns, learning disabilities, and the need for additional interventions like speech, occupational or physical therapies.
- Ensure parents know how to access appropriate school services.
- Ensure family-centered team collaboration.
- Support the parents in advocating for needed supports.
Referrals
Developmental-Behavioral Pediatrics
Refer for help with differential diagnoses, sorting out factors contributing to developmental delays, or for more challenging patients. Developmental-behavioral pediatricians can help differentiate between FASD and ASD or help solidify the co-occurrence of these diagnoses.
Psychiatry/Medication Management
Referral to a psychiatrist may be particularly helpful as psychiatric symptoms in children with FASD and ASD are very common among several symptom domains, including executive functioning deficits, emotional dysregulation, and sleep difficulties. There are also often comorbid psychiatric concerns, including ADHD, anxiety, or mood disorders, which psychiatrists can help diagnose and treat.
Early Intervention for Children with Disabilities/Delays
Early detection and intervention is critical for improving outcomes. Several low-cost programs involve in-home therapy and/or therapy within a playgroup. Each state provides early intervention services differently. In Utah, a diagnosis of FAS or ASD automatically qualifies the child for services. If a diagnosis cannot be established, documentation of developmental delay can help the child to qualify for the program.
School Districts/Special Education
Each school district will have an office responsible for ensuring appropriate services are provided to qualifying students. Contact the district officials if the school is unable or unwilling to offer needed services. Special education services can be provided for children over the age of 3 years (qualification for Early Intervention services ends at age 3).
Bibliography
Benson, A. A., Mughal, R., Dimitriou, D., & Halstead, E. J. (2023). Towards a Distinct Sleep and Behavioural Profile of Fetal Alcohol Spectrum Disorder (FASD): A Comparison between FASD, Autism and Typically Developing Children. Journal of Integrative Neuroscience, 22(3), 77. https://doi.org/10.31083/j.jin2203077
Bishop, S., Gahagan, S., & Lord, C. (2007). Re-examining the core features of autism: A comparison of autism spectrum disorder and fetal alcohol spectrum disorder. Journal of Child Psychology and Psychiatry, and Allied Disciplines, 48(11), 1111–1121. https://doi.org/10.1111/j.1469-7610.2007.01782.x
Carpita, B., Migli, L., Chiarantini, I., Battaglini, S., Montalbano, C., Carmassi, C., Cremone, I. M., & Dell’Osso, L. (2022). Autism Spectrum Disorder and Fetal Alcohol Spectrum Disorder: A Literature Review. Brain Sciences, 12(6), 792. https://doi.org/10.3390/brainsci12060792
Lange, S., Rehm, J., Anagnostou, E., & Popova, S. (2018). Prevalence of externalizing disorders and Autism Spectrum Disorders among children with Fetal Alcohol Spectrum Disorder: Systematic review and meta-analysis. Biochemistry and Cell Biology = Biochimie Et Biologie Cellulaire, 96(2), 241–251. https://doi.org/10.1139/bcb-2017-0014
Maenner, M. J., Shaw, K. A., Baio, J., EdS1, Washington, A., Patrick, M., DiRienzo, M., Christensen, D. L., Wiggins, L. D., Pettygrove, S., Andrews, J. G., Lopez, M., Hudson, A., Baroud, T., Schwenk, Y., White, T., Rosenberg, C. R., Lee, L.-C., Harrington, R. A., … Dietz, P. M. (2020). Prevalence of Autism Spectrum Disorder Among Children Aged 8 Years—Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2016. Morbidity and Mortality Weekly Report. Surveillance Summaries (Washington, D.C.: 2002), 69(4), 1–12. https://doi.org/10.15585/mmwr.ss6904a1
May, P. A., Gossage, J. P., Kalberg, W. O., Robinson, L. K., Buckley, D., Manning, M., & Hoyme, H. E. (2009). Prevalence and epidemiologic characteristics of FASD from various research methods with an emphasis on recent in-school studies. Developmental Disabilities Research Reviews, 15(3), 176–192. https://doi.org/10.1002/ddrr.68
Shaffer, R. C., Reisinger, D. L., Schmitt, L. M., Lamy, M., Dominick, K. C., Smith, E. G., Coffman, M. C., & Esbensen, A. J. (2023). Systematic Review: Emotion Dysregulation in Syndromic Causes of Intellectual and Developmental Disabilities. Journal of the American Academy of Child and Adolescent Psychiatry, 62(5), 518–557. https://doi.org/10.1016/j.jaac.2022.06.020
Stevens, S. A., Nash, K., Koren, G., & Rovet, J. (2013). Autism characteristics in children with fetal alcohol spectrum disorders. Child Neuropsychology: A Journal on Normal and Abnormal Development in Childhood and Adolescence, 19(6), 579–587. https://doi.org/10.1080/09297049.2012.727791
Article History
Previously, this article was published by the Medical Home Portal. The Medical Home Portal, retired in July 2024, provided diagnosis and management information for pediatric conditions, guidance for immediate steps after a positive newborn screen result, and in-depth family education to improve outcomes for children with complex medical care needs. The full archive can be found at the Medical Home Portal Archive.
Topical Reviews in Pediatrics (TRIP) includes archival and updated content from the Medical Home Portal and features new, contemporary topics in pediatrics. A
- 2017 first publication: Deborah Bilder, MDA; Patrick Shea, MDR
AAuthor; CAContributing Author; SASenior Author; RReviewer
