Cholesterol in ASD: Characterization and Treatment

Pilot work suggests that some individuals with autism spectrum disorder (ASD) have very low blood cholesterol levels. This low cholesterol level and other abnormal sterol levels may be important markers for subtypes of ASD.

Evidence for the role of low cholesterol in causing ASD symptomatology in a subgroup of individuals comes from five sources: first, half of the individuals with Smith-Lemli-Opitz syndrome (SLOS) meet the behavioral criteria for autistic disorder (Tierney et al, 2001) and three quarters have some type of ASD (Sikora et al, 2006). Second, in individuals with SLOS, the lower the cholesterol was in the blood and cerebrospinal fluid, the more severe were the autism and IQ and adaptive function deficits. Third, in SLOS, improvement in social and communication abilities was found with added dietary cholesterol. Fourth, cholesterol was low in a pilot study of 100 children with ASD of unknown cause (Tierney et al, 2006), as well as an unpublished expansion of that dataset, and an additional ASD population. Fifth, it is becoming increasingly clear that cholesterol plays a pivotal role in several aspects of brain development.

Three sites (Kennedy Krieger Institute [KKI], Ohio State University [OSU], and the National Institutes of Health [NIH]) will collaborate to accomplish the objectives of this study.

This proposal is designed to 1) determine the prevalence of hypocholesterolemia (> 2 standard deviations below the mean) in ASD individuals; 2) determine the prevalence of hypercholesterolemia (> 2 standard deviations above the mean) in ASD individuals; 3) determine the rate of SLOS in the ASD subjects; 4) create a repository of biomaterial samples from individuals with ASD.

Importance of this Research: These findings will guide the medical community in identifying individuals with ASD who should be tested for sterol disorders.

Of note, the other sites, Ohio State University [OSU], and the National Institutes of Health [NIH]) have IRB approval to perform the above listed aims, as well as to (A) determine the phenotype (physical, behavioral, and developmental) of ASD individuals with either hypocholesterolemia (defined as at or below the 5th centile of age-matched and sex-matched typical population: ASD+Hypo); hypercholesterolemia (defined as at or above the 95th centile of age-matched and sex-matched typical population:ASD+Hyper); or normal cholesterol (ASD+Normal); and (B) test the efficacy of dietary cholesterol supplementation in ASD individuals with cholesterol at the 5th centile or lower; and (C) create a repository of biomaterial samples from individuals with ASD and their biological family members. Each of those sites have approval for 300 ASD subjects and 120 family members.

Participate in Research:

If you or someone you know is interested in participating in this study, please download this informational flyer for more information.