Serum leptin level measured 48 h after delivery is associated with development of postpartum depressive symptoms: a 3-month follow-up study

The aim of this study was to assess the possible relationship between leptin status and postpartum depressive symptoms using serum levels of leptin collected 24-48 h after delivery in a cohort Chinese sample. Women delivering a full-term, singleton, and live-born infant in the period from August 2013 to March 2014 were enrolled immediately postpartum. A blood sample was obtained 24-48 h after childbirth to test serum levels of leptin. Participation consisted of a visit in an obstetric unit at 3 months after delivery. The Edinburgh Postnatal Depression Scale (EPDS), completed at 3 months postpartum, was used to classify each woman's depression symptom severity. Demographic, obstetric, behavioral risk, mental health, and psychosocial factors were considered. Multiple logistic regression analyses were used to identify risk factors most predictive of postpartum depressive symptoms. During the study period, 407 individuals were included and completed follow-up. At 3 months, according to EPDS score, 53 women (13.0 %) were considered as postpartum depressive symptoms. Serum leptin levels in women with PPD were significantly greater than those in women without depressive symptoms (36.5 [IQR, 25.5-50.4] vs. 14.5 [IQR, 9.4-22.4] ng/ml, P < 0.0001). Based on the ROC curve, the optimal cutoff value of serum leptin levels as an indicator for predicting of depressive symptoms was projected to be 24.3 ng/mL, which yielded a sensitivity of 88.7 % and a specificity of 73.4 %, with the area under the curve at 0.867 (95 % CI, 0.817-0.916). In multivariate analysis, there was an increased risk of depressive symptoms associated with leptin levels aeyen24.3 ng/ml (OR 8.234; 95 % CI, 3.572-15.876; P < 0.0001) after adjusting for possible confounders. Elevated serum leptin levels at delivery could eventually serve as a biological marker for the prediction of depressive symptoms. These associations were independent of other possible variables.