Depressive symptoms and proinflammatory cytokines across the perinatal period in African American women

Abstract

Background: Comparatively few studies have examined the biological mechanisms that may underlie the reported racial disparities in antenatal and postpartum depression.

Objective: To examine the associations among race, depressive symptoms and the proinflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α across the perinatal period in a diverse sample of healthy pregnant women at elevated psychosocial risk.

Methods: 171 subjects were enrolled. Women were interviewed and blood samples drawn at 18 and 32 weeks gestation and 6 weeks and 6 months postpartum. Depressive symptoms were measured using the Edinburgh Postnatal Depression Scale. Serum levels of IL-6 and TNF-α were assayed using high sensitivity enzyme-linked immunosorbent assay kits.

Results: Compared with non-African American (AA) women, AA women had significantly higher levels of IL-6 (est. diff = 0.521, p = 0.02, confidence interval (CI): 0.088–0.954) but not TNF-α across all time points (est. diff = −0.060, p = 0.80, CI: −0.517 to 0.397). IL-6 was not associated with depressive symptoms but differences in IL-6 were accounted for by greater Body Mass Index in AA women.

Conclusions: Compared with non-AA women, AA women entered pregnancy with elevated inflammatory cytokine levels that persisted across the perinatal period. This group difference in inflammation did not suggest increased risk for depression, but suggests other implications for long-term health.

• Antenatal depression
• depression
• obesity
• postpartum depression
• proinflammatory cytokines
• race

Declarations of interest

The authors report no declarations of interest.

Current knowledge on the subject

• African American (AA) women have been suggested to be at increased risk of depression during the perinatal period.

• Patients with depression have elevated levels of IL-6 and TNF-α, but it is not clear if this relationship extends to the perinatal period and whether there are racial differences.

What this study adds

• AA women had similar rates of antenatal depression, but higher rates of postpartum depression compared with non-AA women.

• AA women entered pregnancy with elevated IL-6 levels that persisted across the perinatal period, but this was not associated with depressive symptoms.

• The difference in IL-6 levels was likely driven by increased BMI in AA women which has implications for the long-term health outcomes of these women.