Causal Relationship Between Ferritin and Neuropsychiatric Disorders: A Two-Sample Mendelian Randomization Study

Area of Science:

• Neuroscience
• Genetics
• Epidemiology

Background:

• Observational studies suggest a link between ferritin levels and neuropsychiatric disorders.
• The causal relationship between ferritin and these conditions remains unclear.

Purpose of the Study:

• To investigate the potential causal relationship between plasma ferritin levels and neuropsychiatric disorders using genetic data.

Main Methods:

• A two-sample Mendelian randomization (MR) study design was employed.
• Genetic instruments for ferritin were sourced from genome-wide association studies (GWAS).
• Summary statistics for neuropsychiatric disorders were obtained from five GWAS datasets, with inverse variance weighted (IVW) and other MR methods used for analysis.

Main Results:

• A significant causal relationship was found between plasma ferritin levels and an increased risk of Alzheimer's disease (OR=1.06, p=0.037) and Parkinson's disease (OR=1.06, p=0.041).
• Sensitivity analyses indicated no significant heterogeneity or pleiotropy.
• No causal association was identified between ferritin and amyotrophic lateral sclerosis, schizophrenia, or major depressive disorder.

Conclusions:

• This MR study provides genetic evidence for a causal link between plasma ferritin and increased risk of Alzheimer's and Parkinson's diseases.
• Further research is needed to elucidate the underlying genetic mechanisms of this association.