Treating postnatal depressive symptoms in primary care: a randomised controlled trial of GP management, with and without adjunctive counselling

Postnatal depression (PND), defined as an episode of major or minor depression occurring in the first 12 months postpartum, has a point prevalence of 13% at 3 months postpartum [1] and early intervention is indicated to prevent long-term impact on women, their partners and infants [2]. Universal assessment of PND is becoming best practice in many countries around the world [3‐5]. Whilst assessment methods recommended vary (e.g., psychometric screening questionnaires, case-finding questions), these developments in practice will see increasing numbers of cases of PND identified, making widespread availability of effective PND care pathways a pressing public health issue in many countries.

General Practitioners (GPs) and postnatal nurses are key primary care professionals engaged with mothers during the postnatal period. It is therefore important to determine whether best-practice management of PND in primary care can offer an effective pathway resulting in alleviation of depression for the majority of women.

Further as many women are reluctant to take antidepressants during lactation, due to potential side effects on the newborn [6] readily available non-pharmacological treatments are essential. Systematic and meta-analytic reviews support the efficacy of psychological therapy for PND [7, 8]; however, there have generally been too few studies included to draw conclusions about the relative effects of various types of psychological treatments. Nevertheless, cognitive-behavioural therapy (CBT) is clearly one of the most effective treatments for depression at other life stages [9].

Whilst CBT is generally delivered by mental health specialists such as psychologists, some evidence for the ability of nurses to deliver psychological interventions for PND in primary care has been published. However, studies conducted to date have not explicitly compared such interventions to management by GPs. To our knowledge, in the postnatal period, five controlled trials have evaluated psychologically-informed interventions delivered by primary care practitioners (generally nurses) [10‐14]. Only one study [14] has compared non-specialists with specialists (allocation to specialists versus non-specialists was not random).The interventions were CBT-based or counselling-based (psychodynamic therapy was also evaluated in one study), and the nurses were trained in these approaches. With the exception of one study [12], nurse delivered interventions were shown to be more effective in the short-term than routine care (which consisted in most cases of standard nursing practices in place for perinatal women). Morrell et al. [11] also found that benefits for women in the intervention group were maintained at 12 months postpartum. Interestingly, Cooper et al. [10] found an expertise effect, such that women treated by non-specialists showed significantly greater reduction in depressive symptoms compared with those treated by specialists (however treatment allocation was not randomised).

Effective and manualised psychological interventions can be successfully translated to widespread delivery by a range of primary care professionals and could be a valuable resource for health systems around the world. For example, in Australia, the advent of the National Perinatal Depression Initiative (NPDI [15]) will see the implementation of universal screening for perinatal mood disorders. As a large number of depressed women will be identified following screening, it is important to establish which primary care pathways commonly provided in most countries can provide effective treatment of PND. Assessment without evidence-based treatment being readily available raises duty of care issues and, in isolation from other service improvements, screening for depression in primary care will generally be ineffective in reducing morbidity or improving outcomes [16].

The present study similarly sought to examine the effectiveness of counselling informed by the principles of CBT and delivered by primary care practitioners to women with PND. In addition, this study sought to address currently unanswered questions: Is the same treatment delivered by different professionals similarly effective (e.g. trained nurses versus psychologists)? In this RCT we compare three model care pathways: management by trained GPs alone and management by trained GPs augmented with a counselling-CBT intervention delivered either by a trained nurse or a psychologist.

This study compared three pathways of care for managing PND, all treatments requiring training the key primary care health professionals involved. An important question in the management of perinatal mood disorders is whether different "real world" care pathways actually result in amelioration of depressive symptoms, and whether they differ consistently in efficacy [26]. On average, women who were offered GP management in the present study had similar improvements in symptoms of depression and anxiety to those receiving adjunctive counselling-CBT per se. Possibly, the GP training component made any additional effect of adjunctive counselling-CBT more difficult to detect. Nonetheless, we also found that women in GP management continued to exhibit a higher frequency of above-threshold depressive symptoms post-study. These data may suggest that adjunctive counselling-CBT involving either psychologists or nurses could be a promising model of collaborative PND management in primary care.

A number of other positive outcomes were found. Firstly, anxiety, (which is often a co-morbid problem with PND) was also effectively reduced by treatment. Secondly, compliance rates were good and women in all groups showed significant reductions in post-study symptoms of depression. Interestingly, there is some suggestion that adjunctive counselling-CBT was most effective when delivered by nurses. This is consistent with some previous findings on the effectiveness of PND treatment programs delivered by both specialist and trained non-specialist practitioners [11, 12, 27, 14]. In the present study, psychologists worked from treatment rooms in a public hospital whilst nurses conducted the first counselling-CBT session at home and subsequent sessions in a health centre. Conceivably, this difference may have contributed to the possible advantage of counselling-CBT delivered by nurses. Baseline BDI-II scores may also have influenced these results, as they were somewhat higher in group C (counselling-CBT with psychologists).

The study has a number of limitations. First, the sample size was relatively small, and attrition reduced this further at follow-up, limiting our ability to generalise from the results. Second, the "control" group itself involved an enhancement of current care, by training GPs. For ethical reasons it was inappropriate to include a wait-listed control group in this study. However the observed improvements in mood (a drop of 17.3 BDI-II points on average) are of a magnitude at least as large as post-treatment effect sizes observed in studies involving psychological interventions versus routine care for PND [8]. Furthermore, in our previous RCT of psychological treatments for PND [21] we found that, following routine care, symptoms of depression and anxiety were essentially unchanged after 12 weeks. Thus, spontaneous improvement seems an insufficient explanation for the large drop in symptomatology following treatment observed in the present study. Third, GP report of depressive symptoms rather than a standardized diagnostic interview was used for inclusion. However, all GPs were trained in diagnosis according to standard criteria and baseline BDI-II scores in all three groups reflected moderate to severe levels of symptomatology. Furthermore, a single psychologist delivered the intervention, again limiting the generalisability of results. The study is also limited in that no diagnostic procedure was carried out post-treatment, so that the numbers of women meeting diagnostic criteria for a depressive disorder following treatment is not known. Referral to the study was relatively low, and of those referred most either could not be contacted (n = 33) or had experienced improved mood (n = 33). Only 8 women still experiencing low mood and not accessing treatment refused involvement with the study. Lastly, no longer-term follow-up was possible so that long-term maintenance of gains cannot be assessed.

Early intervention for PND is essential due to the negative consequences for women and for their close family members in terms of mental health and child socio-emotional development [28, 29]. The results presented here add to a growing body of evidence that following a positive screening result for PND many (indeed most) women do not pursue further options for assessment and treatment. Less than 50% of women affected by PND have been reported by others to access treatment [18, 30‐32]. In this study, only 20% of those screening positive did so and this may have been partly due to nurse's and women's reluctance to participate in a randomised research study.

Even among those who agreed to referral to this study, most did not ultimately take up treatment, although some cited improved mood or had already accessed other treatment options. Low referral rates to, and participation rates in a particular research study such as this may also reflect the reluctance of women to take part in research.

However, given the current evidence, it seems clear that specific research on how to increase women's engagement with treatment would be valuable. Whilst systematic screening for PND offers one possibility for increasing detection (the first step to accessing treatment) data on the ultimate usefulness of screening programs for PND in terms of increased treatment uptake are still relatively scarce. As has been pointed out elsewhere, the introduction of screening in isolation will have little impact [16, 33]. In the only published RCT of screening effectiveness [34] a significant reduction in morbidity was found due to the implementation of screening. The key to effectiveness in terms of improving women's outcomes was to systematically follow up all positive screening results with further clinical assessment for depression and access to effective management. Recent meta-analyses of the effectiveness of depression screening (not just for PND) suggest that it can have its biggest impact on morbidity when deployed as part of a well-coordinated health system effort towards identification and treatment. A clear policy of acting on all positive screening results plus a well-resourced treatment component appear to maximise the usefulness of screening for depressive disorders in general [16] and the effectiveness and cost-effectiveness of PND screening in particular [34‐36].

In summary, for the majority of those who received treatment, all three possible models of care appeared effective. It therefore appears that for the management of moderate-to-severe PND, best practice primary care management routes are effective for the majority of women. GP management coupled with adjunctive counselling-CBT yielded promising results. In practice these models of PND management are deliverable by existing primary care professionals. However, rates of both referral to treatment (51%), and subsequent treatment uptake (40%) were low, suggesting help-seeking remains an issue in clinical practice that needs to be addressed by comprehensive research on methods to overcome this obstacle. Training key primary care professionals and strengthening their collaboration is likely to remain centrally important for improving current treatment pathways for PND following screening, under Australia's National Perinatal Depression Initiative, and for similar universal programs in other countries.