Causal relationships between atopic dermatitis and psychiatric disorders: a bidirectional two-sample Mendelian...

Area of Science:

• Genetics
• Psychiatry
• Dermatology

Background:

• Observational studies suggest links between atopic dermatitis (AD) and psychiatric disorders, but causality is unclear.
• Existing research indicates potential associations, necessitating further investigation into the directionality of these relationships.

Purpose of the Study:

• To evaluate the bidirectional causal relationship between atopic dermatitis (AD) and several psychiatric disorders.
• To investigate causality for autism spectrum disorder (ASD), major depressive disorder (MDD), attention deficit hyperactivity disorder (ADHD), bipolar disorder (BD), anorexia nervosa (AN), Tourette syndrome (TS), schizophrenia, and anxiety.

Main Methods:

• Utilized bidirectional two-sample Mendelian randomization (MR) analysis.
• Employed summary statistics from large-scale genome-wide association studies for AD and psychiatric disorders.
• Applied multiple MR methods, including inverse variance weighted and MR-Egger regression, to ensure robustness.

Main Results:

• Found a significant causal association between liability to AD and increased risk of ADHD and ASD.
• Identified liability to ADHD, AN, and BD as associated with an increased risk of AD.
• Confirmed that the causal association between AD and ASD was robust and free from reverse effect bias.

Conclusions:

• Emphasizes a significant causal link between atopic dermatitis (AD) and an increased risk of autism spectrum disorder (ASD).
• Identifies bipolar disorder (BD) and anorexia nervosa (AN) as significant risk factors contributing to the development of AD.
• Highlights the complex interplay between dermatological and psychiatric conditions, supporting a bidirectional causal relationship.