Association between birth by caesarian section and anxiety, self-harm: a gene-environment interaction study using UK Biobank data

Background Limited efforts have been paid to explore the underlying genetic mechanisms of birth by caesarian section (CS) affecting the risks of adult anxiety and self-harm. Methods Using UK Biobank cohort, the logistic regression model was first applied to evaluate the associations of adult anxiety and self-harm with birth by CS. Using birth by CS as exposure variables, genome-wide by environment interaction study (GWEIS) was then applied by PLINK2.0 to identify associated genes interacting with birth by CS for anxiety and self-harm. Results In the observational study, significant associations were observed between birth by CS and anxiety (odds ratio (OR) = 1.24; 95% confidence interval (CI), 1.12–1.38; P = 4.86 × 10 − 5 ), and self-harm (OR = 1.12; 95% CI, 1.01–1.24; P = 2.90 × 10 − 2 ). GWEIS revealed multiple suggestive genes interacted with birth by CS for anxiety, such as DKK2 (rs13137764, P = 1.24 × 10 − 9 , adjusted P = 2.68 × 10 − 7 ) and ATXN1 (rs62389045, P = 4.38 × 10 − 8 , adjusted P = 3.55 × 10 − 6 ). For self-harm, significant gene-environment interactions of birth by CS on self-harm were detected, such as ALDH1A2 (rs77828167, P = 1.62 × 10 − 8 ; rs116899929, P = 1.92 × 10 − 8 ) and DAB1 (rs116124269, P = 3.20 × 10 − 8 ; rs191070006, P = 3.63 × 10 − 8 ). Conclusions Our results suggested that birth by CS was associated with the risk of adult anxiety and self-harm. We also discovered some genes interacted with birth by CS might influence the risk of anxiety and self-harm, which may provide novel clues for the pathogenesis of those mental disorders.