Rebecca J Landa1, Alden L Gross, Elizabeth A Stuart, Margaret Bauman. 1. Center for Autism and Related Disorders, Kennedy Krieger Institute, Psychiatry and Behavioral Sciences, The Johns Hopkins University School of Medicine, Baltimore, MD 21211, USA. landa@kennedykrieger.org
Abstract
BACKGROUND: Siblings of children with autism (sibs-A) are at increased genetic risk for autism spectrum disorders (ASD) and milder impairments. To elucidate diversity and contour of early developmental trajectories exhibited by sibs-A, regardless of diagnostic classification, latent class modeling was used. METHODS: Sibs-A (N = 204) were assessed with the Mullen Scales of Early Learning from age 6 to 36 months. Mullen T scores served as dependent variables. Outcome classifications at age 36 months included: ASD (N = 52); non-ASD social/communication delay (broader autism phenotype; BAP; N = 31); and unaffected (N = 121). Child-specific patterns of performance were studied using latent class growth analysis. Latent class membership was then related to diagnostic outcome through estimation of within-class proportions of children assigned to each diagnostic classification. RESULTS: A 4-class model was favored. Class 1 represented accelerated development and consisted of 25.7% of the sample, primarily unaffected children. Class 2 (40.0% of the sample), was characterized by normative development with above-average nonverbal cognitive outcome. Class 3 (22.3% of the sample) was characterized by receptive language, and gross and fine motor delay. Class 4 (12.0% of the sample), was characterized by widespread delayed skill acquisition, reflected by declining trajectories. Children with an outcome diagnosis of ASD were spread across Classes 2, 3, and 4. CONCLUSIONS: Results support a category of ASD that involves slowing in early non-social development. Receptive language and motor development is vulnerable to early delay in sibs-A with and without ASD outcomes. Non-ASD sibs-A are largely distributed across classes depicting average or accelerated development. Developmental trajectories of motor, language, and cognition appear independent of communication and social delays in non-ASD sibs-A.
BACKGROUND: Siblings of children with autism (sibs-A) are at increased genetic risk for autism spectrum disorders (ASD) and milder impairments. To elucidate diversity and contour of early developmental trajectories exhibited by sibs-A, regardless of diagnostic classification, latent class modeling was used. METHODS: Sibs-A (N = 204) were assessed with the Mullen Scales of Early Learning from age 6 to 36 months. Mullen T scores served as dependent variables. Outcome classifications at age 36 months included: ASD (N = 52); non-ASD social/communication delay (broader autism phenotype; BAP; N = 31); and unaffected (N = 121). Child-specific patterns of performance were studied using latent class growth analysis. Latent class membership was then related to diagnostic outcome through estimation of within-class proportions of children assigned to each diagnostic classification. RESULTS: A 4-class model was favored. Class 1 represented accelerated development and consisted of 25.7% of the sample, primarily unaffected children. Class 2 (40.0% of the sample), was characterized by normative development with above-average nonverbal cognitive outcome. Class 3 (22.3% of the sample) was characterized by receptive language, and gross and fine motor delay. Class 4 (12.0% of the sample), was characterized by widespread delayed skill acquisition, reflected by declining trajectories. Children with an outcome diagnosis of ASD were spread across Classes 2, 3, and 4. CONCLUSIONS: Results support a category of ASD that involves slowing in early non-social development. Receptive language and motor development is vulnerable to early delay in sibs-A with and without ASD outcomes. Non-ASD sibs-A are largely distributed across classes depicting average or accelerated development. Developmental trajectories of motor, language, and cognition appear independent of communication and social delays in non-ASD sibs-A.
Authors: Tony Charman; Gregory S Young; Jessica Brian; Alice Carter; Leslie J Carver; Katarzyna Chawarska; Suzanne Curtin; Karen Dobkins; Mayada Elsabbagh; Stelios Georgiades; Irva Hertz-Picciotto; Ted Hutman; Jana M Iverson; Emily J Jones; Rebecca Landa; Suzanne Macari; Daniel S Messinger; Charles A Nelson; Sally Ozonoff; Celine Saulnier; Wendy L Stone; Helen Tager-Flusberg; Sara Jane Webb; Nurit Yirmiya; Lonnie Zwaigenbaum Journal: Autism Res Date: 2016-07-15 Impact factor: 5.216
Authors: Charlotte E Lane; Emily A Bobrow; Diuedonne Ndatimana; Gilles F Ndayisaba; Linda S Adair Journal: Matern Child Nutr Date: 2019-01-29 Impact factor: 3.092
Authors: Daniel Messinger; Gregory S Young; Sally Ozonoff; Karen Dobkins; Alice Carter; Lonnie Zwaigenbaum; Rebecca J Landa; Tony Charman; Wendy L Stone; John N Constantino; Ted Hutman; Leslie J Carver; Susan Bryson; Jana M Iverson; Mark S Strauss; Sally J Rogers; Marian Sigman Journal: J Am Acad Child Adolesc Psychiatry Date: 2013-02-08 Impact factor: 8.829
Authors: Fadila Serdarevic; Akhgar Ghassabian; Tamara van Batenburg-Eddes; Tonya White; Laura M E Blanken; Vincent W V Jaddoe; Frank C Verhulst; Henning Tiemeier Journal: Autism Res Date: 2017-02-09 Impact factor: 5.216
Authors: Eric Rubenstein; Lisa D Wiggins; Laura A Schieve; Chyrise Bradley; Carolyn DiGuiseppi; Eric Moody; Juhi Pandey; Rebecca Edmondson Pretzel; Annie Green Howard; Andrew F Olshan; Brian W Pence; Julie Daniels Journal: Autism Date: 2018-01-29