Investigating the causal risk factors for self-harm by integrating Mendelian randomisation within twin modelling.
Kai Xiang LimOlakunle Ayokunmi OginniKaili RimfeldJean-Baptiste PingaultFrühling RijsdijkPublished in: Behavior genetics (2022)
Previous genetically informed studies have uncovered likely causal relationships between mental health problems and self-harm but resulting causal estimates may be biased due to unmediated pleiotropy. By fitting Mendelian Randomization - Direction of Causation (MR-DoC) models that explicitly model pleiotropy, we investigated the effect of four quantitatively measured mental health problems - major depressive disorder (MDD), schizophrenia, attention-deficit hyperactivity disorder (ADHD), and insomnia, on non-suicidal self-harm (NSSH) and suicidal self-harm (SSH), separately. We used data of 12,723 twins (56.6% females) in the Twins Early Development Study. Besides substantial pleiotropy, we found effects from child-rated depressive symptoms to both NSSH (β = 0.194, 95% CIs: 0.131, 0.257) and SSH (β = 0.210, 95% CIs: 0.125, 0.295). Similarly, effects flowed from parent-rated depressive symptoms to NSSH (β = 0.092, 95% CIs: 0.004, 0.181) and SSH (β = 0.165, 95% CIs: 0.051, 0.281). We did not find evidence of aetiological difference between NSSH and SSH.
Keyphrases
- mental health
- depressive symptoms
- attention deficit hyperactivity disorder
- major depressive disorder
- bipolar disorder
- autism spectrum disorder
- mental illness
- social support
- sleep quality
- working memory
- magnetic resonance
- electronic health record
- big data
- machine learning
- mass spectrometry
- physical activity
- data analysis
- atomic force microscopy
- artificial intelligence
- high speed