Relationship of Psychiatric Disorders to Measures of Child Function in Parents of Children with Autism

Article excerpt

Genetic and environmental contributions from parental psychiatric disorders may partially explain the heterogeneity of autism in children. Few studies, however, have utilized structured interviews or examined parental psychiatric status with regard to child functioning. We completed structured psychiatric interviews on 23 parents of children with autism as well as symptom severity and cognitive measures on the children. Fifteen parents (65%) met lifetime criteria for a DSM-IV Axis I psychiatric disorder. Parental psychiatric history was associated with a parent report measure of symptom severity in children but not with measures derived from clinical observations. Keywords: intellectual disability, autism, ADOS, family, depression, mood disorder, psychiatric

Autism is a disorder characterized by impairments in social interaction and communication and a restricted range of behaviors and interests. (4) Twin studies have shown that autism is highly heritable. Monozygotic concordance rates range from 36% to 91% (versus dizygotic concordances of 0%-23%), and overall autism spectrum heritability rates are estimated to be as high as 90%. (5,18,40,50)

Increased rates of social and communication deficits in first-degree relatives of persons with autism also suggest the heritability of the broader autism phenotype. (5,8,18,19,50) In addition to the broader autism phenotype, family studies have also found increased rates of psychiatric disorders, particularly affective disorders, in relatives of persons with autism. High rates of major depressive disorder (MDD) in first degree relatives (ranging from 20%-37%) have been consistently identified, especially for recurrent and early onset MDD. (9,34,35,47) There is some suggestion that rates of single episodes of major depression, dysthymia, and minor depressive disorder are also increased in families of persons with autism as compared to the general population, but are not higher than parents of children with other developmental disabilities. (25) DeLong and Dwyer (14) found increased rates of bipolar disorder in first degree relatives of children with Asperger syndrome; however, subsequent research has not replicated that finding in relatives of children with autistic disorder in general. (1,9,34,35,47)

Many studies have also reported increased rates of anxiety disorders, especially social phobia, in first degree relatives of persons with autism. (29,34,35,47) However, Bolton et al. (9) did not find increased rates of any anxiety disorders in the relatives of children with autism compared to relatives of individuals with Down syndrome.

There are conflicting reports on the rates of other psychiatric disorders (e.g., alcohol abuse, drug abuse, eating disorders, and somatoform disorders) in the relatives of persons with autism. Smalley et al. (47) reported a significant increase in the rate of substance abuse in families of children with autism. Abramson et al. (1) did not report an increased rate of drug abuse but did find a significant increase in alcohol abuse. Other studies have not replicated this finding. (9,29,35) The few studies that have examined rates of eating disorders in relatives have not found a significant difference between the groups. (9,34,47) We are not aware of any published studies that have included somatoform disorders in investigations of psychiatric disorders in relatives of persons with autism.

Estimates of psychiatric disorders in the general population suggest that women have a higher risk for anxiety and mood disorders than men, but that men are at an increased risk for substance use disorders. (22) However, in a literature review of psychiatric disorders in parents of children with autism, Yirmiya and Shaked (55) did not find significant gender differences in psychiatric disorders. Both mothers and fathers had increased rates of psychiatric disorders compared to parents of typically developing children, children with Down syndrome, and children with severe intellectual disability of unknown etiology. …