Abstract
BACKGROUND: Postpartum depression (PPD) affects maternal mental health extensively and is challenged by the lack of objective diagnostic methods. This study aimed to explore the characteristics of niacin skin flush response, a diagnostic marker for depression, in individuals with PPD and to determine its clinical potential as an adjunctive screening marker. METHODS: A total of 1417 parturients was recruited in this study. Edinburgh Postnatal Depression Scale was used to screen for depression with a cut-off score ≥ 13. The Patient Health Questionnaire-9 scale was used to test the consistency of scale screening. The Chi-square test was used to compare the screening results of the two scales, and the reliability and validity of the two scales were discussed. Mann Whitney U test was used to analyze the differences in niacin-flushing between PPD and healthy controls (HC), and a ten-fold cross-validation with logistic regression was used to verify the potential of niacin-flushing to distinguish between PPD and HC. A screening model for women with PPD was established by bivariate truncation method. RESULTS: The results of the two depression screening scales were 12.85% inconsistent, indicating the nonobjectivity of the scale screening. Compared with the healthy women, women with PPD exhibited significantly attenuated and delayed niacin-induced flushing response. An innovative and user-friendly postpartum depression screening model was established according to the features, by which we could identify women with PPD from healthy women with a sensitivity of 53.09% (95% CI: 42.22% - 63.95%) and a specificity of 73.28% (95% CI: 70.90% - 75.65%). CONCLUSIONS: This study identified the characteristics of impaired niacin response in women with PPD, and established a potential screening standard for PPD, which is highly objective and operable. The niacin-blunted subgroup of PPD may imply a common biological basis, which provokes new thoughts in elucidating the pathological mechanisms of postpartum depression.