(169) Physical activity in pregnancy moderates short and long-term associations between depressive symptoms and psychobiologic markers

Objective: Poor mental health is a leading cause of maternal morbidity and mortality, yet simple interventions that are effective on a biologic level are lacking. We evaluated whether physical activity is associated with improvements in psychobiologic markers in pregnant people with depressive symptoms.

Study Design: We analyzed pregnancies among people enrolled in a prospective cohort from 2009-2010 who had depressive symptoms (Edinburgh Postpartum Depression ­­­Scale [EPDS] score >8) at 26 weeks gestation. We examined: 1) the cross-sectional interaction of EPDS score and physical activity (PA) predicting maternal leukocyte telomere length (LTL), a biomarker of stress and aging when shortened; and 2) whether LTL and PA predict longitudinal change in EPDS scores from pregnancy to 2 years postpartum. PA was categorized as based on report of metabolic equivalent tasks (METs). LTL was reported as telomere/single gene (T/S) ratios from quantitative PCR. We used linear generalized estimating equation regression models, adjusting for confounders.

Results: 235 pregnancies were included. In pregnant people with no PA, higher EPDS scores were related to shorter LTL; this was reversed in people with mild or high PA, in whom LTL lengthening was seen (mild PA: ß=0.02, 95% CI 0.002, 0.04, p=0.03; high PA: ß=0.03, 95% CI -0.001, 0.05, p=0.06; Figure 1). Longitudinally, longer LTL and higher PA levels predicted significant decreases in EPDS scores by 2 years postpartum (mild PA: ß=-12.8, 95% CI -20.1, -5.4, p< 0.01; high PA: ß=-15.3, 95% CI -30.3, -0.19, p=0.047, Figure 2).

Conclusion: In pregnant people with depressive symptoms, physical activity reversed the negative effects of higher EPDS scores on LTL shortening. This was also evident longitudinally: people with the longest LTL and highest PA had a 15-point reduction in EPDS scores by 2 years postpartum compared to people with no PA. Investigation into PA as a treatment for perinatal depressive symptoms is warranted.