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Randomized Controlled Trial
. 2011 Jun;17(6):PI15-23.
doi: 10.12659/msm.881792.

A Prospective Double-Blind, Randomized Clinical Trial of Levocarnitine to Treat Autism Spectrum Disorders

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Free PMC article
Randomized Controlled Trial

A Prospective Double-Blind, Randomized Clinical Trial of Levocarnitine to Treat Autism Spectrum Disorders

David A Geier et al. Med Sci Monit. .
Free PMC article

Abstract

Background: L-carnitine was proposed as a potential treatment for patients diagnosed with an autism spectrum disorder to improve mitochondrial dysfunction, but no prior randomized controlled trials have been conducted.

Material/methods: Thirty subjects diagnosed with an ASD were randomly assigned to receive a standardized regimen (50 mg L-carnitine/kg bodyweight/day) of liquid L-carnitine (n=19) or placebo (n=11) for 3-months. Measures included changes in professionally completed Childhood Autism Rating Scale (CARS), hand muscle testing, and modified clinical global impression (CGI) forms; parent completed Autism Treatment Evaluation Checklist (ATEC), treatment adherence measurement (TAM), frequency and intensity of side effect rating (FISER)/global rating of side effect burden (GRSEB)/patient report of incidence of side effects (PRISE) forms; and lab testing.

Results: Significant improvements were observed in CARS (-2.03, 95% CI=-3.7 to -0.31), CGI (-0.69, 95% CI=-1.1 to -0.06), and ATEC scores. Significant correlations between changes in serum free-carnitine levels and positive clinical changes were observed for hand muscle strength (R2=0.23, P=0.046), cognitive scores (R2=0.27, P=0.019), and CARS scores (R2=0.20, P=0.047). Study subjects were protocol-compliant (average adherence was >85%) and generally well-tolerated the L-carnitine therapy given.

Conclusions: L-carnitine therapy (50 mg/kilogram-bodyweight/day) administered for 3-months significantly improved several clinical measurements of ASD severity, but subsequent studies are recommended.

Figures

Figure 1
Figure 1
The chemical structure of Levocarnitine. Empirical Formula: C7H15NO3; Molecular Weight: 161.20.
Figure 2
Figure 2
Trial profile of L-carnitine.
Figure 3
Figure 3
The correlation* between the change in serum free-carnitine and the change in hand muscle testing score (n=18)**. * simple linear-regression statistic; ** L-carnitine group (n=11) and placebo group (n=7). ____ – linear regression estimate; - - - - – 95% confidence interval for linear regression estimate; Δ Hand Muscle Strength (kPa) =0.22 Δ Serum Free Carnitine (μmol/L) − 1.6; R2=0.23, P=0.046.
Figure 4
Figure 4
The correlation* between the change in serum free-carnitine and the change in cognitive score derived from the ATEC (n=20)**. * simple linear-regression statistic; ** L-carnitine group (n=12) and placebo group (n=8); ____ – linear regression estimate; - - - - – 95% confidence interval for linear regression estimate; Δ Cognitive Score (ATEC) =−0.086 Δ Serum Free Carnitine (μmol/L) − 0.72; R2=0.27, P=0.019.
Figure 5
Figure 5
The correlation* between the change in serum free-carnitine and the change in CARS score (n=20)**. * simple linear-regression statistic; ** L-carnitine group (n=12) and placebo group (n=8); ____ – linear regression estimate; - - - - – 95% confidence interval for linear regression estimate; Δ CARS Score =−0.047 Δ Serum Free Carnitine (μmol/L) − 0.81; R2=0.20, P=0.047.

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References

    1. Autism and Developmental Disabilities Monitoring Network Surveillance Year 2006 Principal Investigators; Centers for Disease Control and Prevention (CDC) Prevalence of autism spectrum disorders – Autism and Developmental Disabilities Monitoring Network, United States, 2006. MMWR Surveill Summ. 2009;58:1–20. - PubMed
    1. Gerlai J, Gerlai R. Autism: a large unmet medical need and a complex research problem. Physiol Behav. 2003;79:461–70. - PubMed
    1. Lombard JL. Autism: a mitochondrial disorder? Med Hypotheses. 1998;50:407–500. - PubMed
    1. Schifter T, Hoffman J, Hattten HP, Jr, et al. Neuroimaging in infantile autism. J Child Neurol. 1994;9:155–61. - PubMed
    1. Minshew NJ, Goldstein G, Dombrowski SM, et al. A preliminary 31PMSR study of autism-evidence for under-synthesis and increased degradation of brain membranes. Biol Psychiatry. 1993;33:762–73. - PubMed

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