Coeliac disease and postpartum depression: are they linked? A two-sample Mendelian randomization study

Area of Science:

• Genetics
• Psychiatry
• Gastroenterology

Background:

• Coeliac disease (CD) is an autoimmune disorder with potential systemic effects.
• Postpartum depression (PPD) is a significant mental health concern affecting women after childbirth.
• Investigating the genetic overlap between CD and PPD may reveal shared etiological factors.

Purpose of the Study:

• To explore potential causal associations between coeliac disease (CD) and postpartum depression (PPD).
• To utilize two-sample Mendelian randomization (MR) analysis for assessing genetic links.
• To examine the relationship between CD and general depression (DP) as a secondary analysis.

Main Methods:

• Employed the IEU OPEN GWAS project to identify genetic loci for CD as instrumental variables (IVs).
• Performed MR analysis using inverse variance weighting (IVW), weighted median, and MR-Egger methods.
• Conducted sensitivity analyses including MR-Egger intercept, Cochran's Q test, and leave-one-out analysis to ensure robustness.

Main Results:

• A statistically significant association was found between genetically predicted risk of CD and PPD (OR = 1.022, 95% CI: 1.001-1.044, P = 0.043).
• No significant causal link was detected between CD and general depression (DP) (OR=0.991, 95% CI: 0.978-1.003, P=0.151).
• Sensitivity analyses indicated no significant horizontal pleiotropy or heterogeneity, supporting the primary findings.

Conclusions:

• Mendelian randomization analysis suggests a potential causal relationship between coeliac disease and postpartum depression.
• The findings highlight a possible genetic connection warranting further investigation into shared pathways.
• No significant association was observed between coeliac disease and general depression.