Identifying depression in the first postpartum year: guidelines for office-based screening and referral

Abstract

Background: Some 10–15% of women experience postpartum-onset major depression (PPMD). The objective of this study was to determine if the Edinburgh Postnatal Depression Scale (EPDS) is an effective screen for major depression (MD) prospectively. The outcome of the study was identification of a recurrence of major depression in the first year postpartum by a clinical interview and the EPDS. We had the unique opportunity to examine the relationship between EPDS scores and PPMD. Methods: Participants were pregnant women who had experienced an episode of previous PPMD but were well during their index pregnancy. This study was part of a double-blind, randomized clinical trial in which new mothers received nortriptyline or placebo within 24 h following delivery for prevention of PPMD. Recurrence of depression was established according to Research Diagnostic Criteria. Participants completed the EPDS weekly through 20 weeks postpartum and into a 1-year follow-up phase. Results: Out of 50 women, 13 experienced recurrence of MD in the first 20 weeks postpartum with a total of 20 out of 50 recurring in the first year. The EPDS score of >9 at week 4 postpartum identified 60% of women who nurtured in the first 20 weeks and 80% who recurred in the first postpartum year. Limitations: The study population included only women who had a previous episode of postpartum depression. The generalizability to all women is limited. Conclusions: The EPDS is an effective depression screen for women who had a previous episode of PPMD. Clinical guidelines are provided for use of the EPDS to identify MD in the first postpartum year in primary care settings.

Introduction

One out of eight women suffers an episode of depression after birth (Byrne, 1984, Kumar and Robinson, 1984, O’Hara et al., 1984, Kendell et al., 1981, Kendell et al., 1987, Cox et al., 1993, Pitt, 1968, Wisner et al., 1993) and 50% of these episodes are not recognized in busy clinical practices (Yonkers and Chantilis, 1995). Postpartum major depression (PPMD) substantially decreases the mothers’ ability to function and affects both new mothers and their families (Philipps and O’Hara, 1991). Children of women with PPMD are at increased risk for impaired cognitive and language development (Field et al., 1990). These children are shown to suffer from behavioral problems for at least 4 1/2 years (Philipps and O’Hara, 1991). Murray (1992) found that infants whose mothers suffered from PPMD showed impaired cognitive development compared to infants whose mothers had no history of depression or to infants whose mothers had a history of depression without postpartum onset. Identification and treatment of depression within the first year postpartum is a critical public health issue and clinicians need a simple screen to identify women who suffer from PPMD.

In the United Kingdom, home health care nurses routinely use the Edinburgh Postnatal Depression Scale (EPDS; Cox et al., 1987) to identify cases of PPMD (see Appendix A). The instrument is brief and contains ten items that are ranked from zero to three. Cox et al. (1987) suggested that a woman who has a total score of >10 on the EPDS should be evaluated for depression. Several investigators validated the EPDS in European community samples and non-postpartum women (Zelkowitz and Milet, 1995, Cox et al., 1996, Wickberg and Hwang, 1996, Murray and Carothers, 1990). At a score of 10, the EPDS has sensitivities that range from 91% (specificity 76%; Cox et al., 1987) to 88% (specificity 72%; Cox et al., 1996) when concurrent diagnoses were made by DSM-III-R or according to Research Diagnostic Criteria (RDC; Zelkowitz and Milet, 1995, Cox et al., 1996, Wickberg and Hwang, 1996, Murray and Carothers, 1990, Harris et al., 1989).

In a sample of American postpartum women, O’Hara (1994) described the use of the EPDS. When a single measurement of depression was taken at 1 month postpartum, an EPDS score of 12 or 13 identified 86% of the cases when RDC was used as the gold standard for a diagnosis of both major and minor depression (O’Hara, 1994). The sensitivity of the EPDS was 72% and the specificity was 100% for major depression.

When used in a residency program, the EPDS increased the detection of PPMD from 6.3% of identified cases to 35.4% (Evins et al., 2000). After implementing the use of the EPDS in a community-based sample of 6-week postpartum women, researchers found that the rate of diagnosis of PPMD increased from 3.7% before EPDS use to 10.7% following routine screening (Georgiopoulos et al., 2001).

Many postpartum women seek help from their obstetricians or primary care physicians who commonly see women with depression in their practices (Yonkers and Chantilis, 1995). In a recent study, Heneghan et al. (2000) suggested that pediatricians take a role in identifying depression in the young mothers of their patients. Mothers who have had an episode of PPMD are justified in their concerns about recurrence, since 26% of these women will suffer an episode after another birth (Wisner et al., 2001). Having a self-report instrument available to these practitioners would help them to identify women in need of treatment. To our knowledge, ours is the first longitudinal study to use the EPDS as a screening tool for identifying current and future episodes of MD in a sample of American women who were at risk for experiencing PPMD.