Diagnosis and classification: challenges and opportunities for perinatal psychology

Broad and overarching issues of the kind discussed in this editorial are of relevance to journal readers, authors and reviewers, from the perspective of both theory and practice and more specifically reproductive psychology. The recent revision to the diagnostic and statistical manual for the diagnosis and classification of psychiatric disorder by the American Psychiatric Association (APA, 2013) has presented many challenges, these being both conceptual and practical. A critical issue remains the paradox of diagnosis by exclusion, the classical differential diagnosis. This is of concern in a number of fields including developmental and health psychology as well as clinical psychology and psychiatry.

In the current revision, this represents a historical legacy related to psychiatry being at its core a branch of medicine, circumscribed by its medical heritage and pathology-oriented principles. The enigma and paradox that is specific to a psychiatric diagnosis is that for the psychiatric diagnosis to be made, organic causation must be ruled out. This presents many challenges compared to other branches of medicine in that, for example, compared to oncology or cardiology, psychiatric diagnoses can be ambiguous and prone to misidentification. An example of this comes from the latest revision of DSM, DSM-5, with considerable implications for those working in children’s mental health services. Asperger syndrome has now vanished as a valid diagnosis within DSM-5 and now forms part of the autism spectrum. This has many ramifications, not only for parents and the children concerned, but also for clinicians and researchers. Irrespective of the underlying accuracy of a diagnosis, for parents concerned about problematic behavioural or communication problems with their children, a confirmatory diagnosis may provide some comfort, the certainty of an answer and the possibility of the provision of an evidence-based intervention and effective treatment. There is a need to consider the impact of this change on parents and families: how is the reality of the certainty of diagnosis received by the parents when this may then be presented as apparently illegitimate and erroneous within a contemporary context? What comfort can be drawn from a child being given a ‘new classification’ and how long can such a new classification be assumed to be legitimate? Irrespective of the type of a diagnosis, the impact on the parents of introducing uncertainty into the care of a loved one may incur a significant psychological burden, which may appear to have a number of effects possibly embodied in a loss of confidence, an increase in anxiety and stress and a decrease in feelings of empowerment within a partnership approach to working with clinical services. The disappearance of Asperger syndrome as a diagnosis from DSM-5 is a tacit example and may be seen as representative of a more difficult problem that faces the whole notion of diagnosis: that of classification. The limitations of such an approach and its impact on clinical decision-making have been noted in terms of potential deleterious effects on service users and families, regardless of age. Importantly, the contribution of psychological models has provided additional evidence to consider carefully the merits or otherwise of a classification approach. Schizophrenia, for example, and its historical classification into either four categories (simple, catatonic, hebephrenic and paranoid) or two categories (negative symptoms dominant or positive symptoms dominant), depending on which particular classification is in vogue and a factor contingent both on professional, regional and cultural variation (noting that Japan has recently changed their terminology for schizophrenia from ‘mind-split disease’ to ‘integration disorder’), is severely limited by developments in the psychological evidence base. For example, stress–vulnerability models of psychosis (Nuchterlein & Dawson, 1984) emphasise the role of anxiety in the manifestation and maintenance of psychotic symptoms, an observation and notion that is central to the development of continuum models of both psychosis and schizophrenia, that describe variation on a range from non-psychotic to psychotic within a normal population (Fleming & Martin, 2012).

This represents a significant challenge within the perinatal period in terms of puerperal psychosis. Importantly, puerperal psychosis represents perhaps the most ‘psychiatric’ presentation seen during the postnatal period, a potentially frightening diagnosis characterised by a perception of ‘madness’ and distinctiveness from ‘normality’. The notion that puerperal psychosis could represent an endpoint on a continuum is challenging to both conventional diagnostic models and accepted treatment approaches. However, if a continuum model of schizophrenia is operative and encapsulated within a stress–vulnerability context has evidence-based legitimacy, can it really be a quantum leap of thinking to consider puerperal psychosis within the same context? There are precedents for this in the literature. It has been established that antenatal anxiety represents a major predictor of postnatal depression (Beck, 2001), an observation that highlights the dynamic influence of anxiety on mood and emotional status. Further, recent focus on genetic factors in puerperal psychosis, for example the association of this presentation with chromosome 16 (Jones et al., 2007), has major ramifications for the conceptualisation and theoretical positions that support aetiological models, and indeed facilitate a review and reconsideration of causation. Contrasting a controversial proposition that puerperal psychosis represents simply a reaction from a new mother who had become disenfranchised by the experience of birth and motherhood, with emerging evidence of genetic influence provides an opportunity to review and compare existing evidence, and to refine aetiological models. However, irrespective of the evidence that has emerged or may emerge over forthcoming years regarding puerperal psychosis or postnatal depression, it is difficult to reconcile such evidence with clinical reality and clinical intervention if the diagnosis becomes invalid, as the recent revisions noted in DSM-5 regarding Asperger syndrome have made clear. If a similar review in a future DSM were to invalidate a major mental health diagnosis or categorisation associated with the perinatal period, what does this say about the legitimacy of contemporary medical management, psychological intervention and psychosocial understanding? The challenge here for the social construction of motherhood is, of course, that new mothers are supposed to be delighted, empowered and committed to their new circumstances and responsibilities from day one, thus deviation from that ideal risks becoming ‘pathologised’ requiring sometimes extreme intervention. This approach is guided and legitimised under the banner of ‘risk management’ of the mother and her new baby requiring medical management rather than psychological understanding. Consequently, if women, their infants and partners are to benefit from the true contribution of what applied psychology can offer to clinical care, it may be time to embrace psychology’s unique perspective of a continuum of experience rather than the reductionist and often less insightful approach of categorisation. The next edition of the journal, focusing on psychological health during the perinatal period, adopts this approach.

Colin R. Martin and Maggie Redshaw