Autoimmune Disease and Perinatal Depression: Bidirectional Link Reported

Women with autoimmune disease, especially multiple sclerosis (MS), have an increased risk for subsequent perinatal depression, and those with perinatal depression have an increased risk for autoimmune disease, according to study findings published in Molecular Psychiatry.

There is lack of evidence on the genetic overlap between depression and autoimmune disease; therefore, researchers aimed to determine this bidirectional association. Specifically, researchers conducted a nested case-control study to examine the association between autoimmune disease and risk for perinatal depression; a matched cohort study to assess the link between perinatal depression and the risk for autoimmune disease; and a sibling comparison to examine the genetic association and risk factors in both perinatal depression and autoimmune disease between siblings.

Participants were identified using the Swedish National Medical Birth Register between 2001 and 2013.

A total of 55,299 women with perinatal depression (mean age at diagnosis, 30.7) and 552,990 without perinatal depression were included in the study. Individuals with vs without perinatal depression were more likely to have a higher body mass index (BMI), pregnancy complications, and psychiatric comorbidities.

Based on results of the nested case-control study, 4590 (8.3%) women with and 30,414 (5.5%) without perinatal depression were found to have an autoimmune disease. After adjustment for demographics and pregnancy characteristics, autoimmune disease was associated with a 30% higher risk for subsequent perinatal depression (odds ratio [OR], 1.30; 95% CI, 1.25-1.35), including antepartum and postpartum depression (ORs, 1.26 and 1.35, respectively).

In the sibling analysis, unaffected sisters of women with autoimmune disease were also found to have higher risk for perinatal depression (OR, 1.29; 95% CI, 1.15-1.45).  

Similarly, women with vs without exposure to perinatal depression had higher rates of autoimmune disease (6.0% vs 3.8%, respectively), as well as a 30% higher subsequent risk for autoimmune disease (hazard ratio [HR], 1.30; 95% CI, 1.25-1.36). Women with antepartum and postpartum depression had HRs of 1.27 and 1.35, respectively.

In the sibling analysis, unaffected sisters of women with perinatal depression also had a higher risk for autoimmune disease (HR, 1.33; 95% CI, 1.12-1.58).

Of note, women without psychiatric comorbidities and with MS were observed to have the most significant association between autoimmune disease and perinatal depression (nested case-control OR, 1.49; 95% CI, 1.42-1.56 and 1.96; 95% CI, 1.64-2.34, respectively; matched cohort HR, 1.42; 95% CI, 1.35-1.51 and 1.79; 95% CI, 1.03-3.11, respectively; P <.001 for both).

Study limitations included the lack of accounting for all cases of perinatal depression in primary care, especially between 2001 and 2005; the lack of a definition for psychiatric comorbidities in outpatient care; and the possible misclassification of autoimmune diseases.

“These findings have implications for research on biological mechanisms, and for healthcare professionals who need to be alert to the risk of PND [perinatal depression] in women with AD [autoimmune disease], and vice versa.”