Trace elements in children with autism spectrum disorder: A meta-analysis based on case-control studies

Area of Science:

• Pediatric Neurodevelopmental Disorders
• Environmental Toxicology
• Nutritional Science

Background:

• Autism spectrum disorder (ASD) is a prevalent childhood neurodevelopmental disorder.
• The potential link between trace elements and ASD is an area of ongoing research with inconsistent findings.
• Understanding these relationships is crucial for potential diagnostic and therapeutic strategies.

Purpose of the Study:

• To conduct a meta-analysis investigating the association between trace elements and autism spectrum disorder (ASD) in children.
• To synthesize existing research to clarify the inconsistent reports on trace elements and ASD.
• To identify specific trace elements that may be elevated or deficient in children with ASD.

Main Methods:

• A comprehensive literature search was performed across PubMed, EMBASE, and Cochrane databases up to November 15, 2019.
• A random-effects model was employed for the meta-analysis.
• Subgroup analyses were conducted based on different sample measurement types.

Main Results:

• Twenty-two studies involving 1014 children with ASD and 999 healthy controls were analyzed, examining 18 trace elements.
• Elevated levels of barium (Ba), mercury (Hg), lithium (Li), and lead (Pb) were found in children with ASD.
• Significant differences in copper (Cu) levels were noted in hair and serum, while hair Hg, Li, Pb, and Se were higher, and blood zinc (Zn) was lower in children with ASD.

Conclusions:

• Excessive exposure to toxic heavy metals and insufficient intake of essential metal elements may be associated with ASD.
• Interventions aimed at preventing toxic metal exposure and addressing dietary deficiencies could be beneficial for ASD prevention and management.
• Further research is warranted to elucidate the complex role of trace elements in ASD etiology and progression.