Association between a single nucleotide polymorphism in the hydroxysteroid (11-beta) dehydrogenase 1 gene and postpartum depression symptoms: the role of neuroticism
(English)Manuscript (preprint) (Other academic)
Postpartum depression is a common psychiatric disorder and numerous studies have assessed its association with psychosocial and biological factors. However, the contribution of genetic factors remains largely unknown. A dysregulated hypothalamus-pituitary-adrenal (HPA) axis and neuroticism associate with depressive symptoms after childbirth. A common genetic variant in the hydroxysteroid (11-beta) dehydrogenase 1 gene (HSD11B1), a component of the HPA-axis, has been recently associated with postpartum depressive symptoms.
To examine the association between the single nucleotide polymorphism (SNP) rs12565406 in HSD11B1 and neuroticism, as well as the possible mediatory role of neuroticism in the association between the polymorphism and postpartum depressive symptoms.
Materials and Methods
The present study was conducted as part of the BASIC-project and included 771 women. Self-administered questionnaires were sent to study participants, containing the Edinburgh Postnatal Depression Scale (EPDS) at six weeks postpartum and questions on demographic variables at pregnancy week 17 and 32 and at six weeks postpartum, as well as the Swedish universities Scale of Personality (SSP) at pregnancy week 32. Blood samples for genetic analyses were collected.
Sixty-five women (8.6%) reported depressive symptoms six weeks postpartum. Study subjects with EPDS ≥ 12 had higher scores on neuroticism compared to controls. Women who were homozygous for the major allele (GG) presented with higher EPDS score postpartum and scored higher in neuroticism, compared to T carriers. Linear regression models with log transformed EPDS score as the dependent variable and the rs12565406 genotype (GG vs. TG/TT) as the independent variable showed an association between the GG genotype and depressive symptoms. When neuroticism was introduced in the model, it was associated with EPDS score, whereas the association between the GG genotype and EPDS became borderline significant. Results were unaltered after adjustment for possible confounders. A path analysis on these variables revealed that neuroticism had a mediatory role in the association between the SNP and EPDS score.
Neuroticism had a mediatory role in the association between the HSD11B1 rs12565406 SNP and postpartum depression. Future studies are needed to ascertain whether neuroticism can be used as an easily assessed intermediate phenotype that can reflect the genetic risk of PPD.
Psychiatry Obstetrics, Gynecology and Reproductive Medicine
IdentifiersURN: urn:nbn:se:uu:diva-274953OAI: oai:DiVA.org:uu-274953DiVA: diva2:897897