Relationships between screen time and childhood attention deficit hyperactivity disorder: a Mendelian randomization...

Area of Science:

• Genetics
• Neuroscience
• Public Health

Background:

• Observational studies suggest a link between childhood attention deficit hyperactivity disorder (ADHD) and screen time.
• However, the causal relationship between screen time and childhood ADHD remains unclear.

Purpose of the Study:

• To investigate the causal association between screen time and childhood ADHD using a bidirectional two-sample Mendelian randomization (MR) analysis.
• To explore whether childhood ADHD influences screen time.

Main Methods:

• Utilized large-scale genome-wide association studies (GWAS) datasets from the Psychiatric Genomics Consortium (PGC) and UK Biobank.
• Selected single nucleotide polymorphisms (SNPs) as instrumental variables for screen time exposure.
• Employed MR-Egger, Inverse Variance Weighted (IVW), and weighted median methods for causal inference, with MR-PRESSO for outlier detection.

Main Results:

• Higher mobile phone use duration (OR, 1.848) and increased television watching time (OR, 2.104) were significantly associated with an increased risk of childhood ADHD.
• Reverse MR analysis found no evidence that childhood ADHD influences screen time.
• Sensitivity analyses indicated no significant horizontal pleiotropy or heterogeneity.

Conclusions:

• This study provides evidence supporting a causal link between specific screen time activities and an increased risk of childhood ADHD.
• The findings suggest that reducing screen time may be a potential strategy for mitigating ADHD risk.
• Further research is warranted to fully elucidate this complex relationship.