Attenuated psychosis syndrome: benefits of explicit recognition

概述

符合轻微精神病综合征（attenuated psychosis syndrome ，APS）标准的个体具有独有的特征，越来越多的文献认为对符合APS标准的个体提供服务在临床上能获益，因而APS的诊断在精神病学中有着重要作用，但过去却被忽视了。推行这一诊断将有助于减少对具有前驱期精神病性状态个体的过度诊断和治疗。因为青少年是被诊断为APS的主要群体，所以也应鼓励那些主要为青少年服务的医生接受关于轻微精神病综合征的全面培训。虽然只有一部分APS个体最终会发展为精神病，但是临床上所有的APS个体都需要得到帮助——无论他们的转归如何。DSM-5正式列出APS，这将有利于开展如何识别这类个体的临床需求以及如何满足这些需求的研究。

中文全文

本文全文中文版从2015年4月8日起在http://dx.doi.org/10.11919/j.issn.1002-0829.215015可供免费阅览下载Prevention of psychotic illness – which can be a devastating condition-has become a growing priority of mental health clinicians and researchers. Advances in the identification of people with attenuated psychotic symptoms, a group generally at increased risk for psychosis, have allowed for the development of novel intervention strategies. These interventions have had promising results, including symptom improvement, better functioning, delayed onset of psychosis, and reduced rates of transition from attenuated to full-threshold psychosis.[1],[2] Moreover, identifying and potentially treating individuals with attenuated psychosis will shorten or completely eliminate the period during which individuals destined to develop psychosis experience psychotic symptoms without treatment (i.e., the ‘duration of untreated psychosis’ or DUP), a change that is related to several positive outcomes, including better response to treatment, higher quality of life, and reduced mortality after the onset of psychotic illness.[3],[4]Given this tremendous potential benefit of early intervention, the importance of a reliable category to identify people with attenuated psychosis is hard to overstate. The field has created a variety of related labels to represent an attenuated, at-risk state, including ‘clinical high-risk,’ ‘ultra high-risk,’ ‘the prodrome,’ and ‘psychosis-risk syndrome.’ The term ‘Attenuated Psychosis Syndrome’ (APS), a construct characterized by attenuated psychotic symptoms that overlap with an at-risk status, has been added to the DSM-5 both as a condition for future study and as one of the possible presentations of Other Specified Schizophrenia Spectrum and Other Psychotic Disorders, 298.8 (F28).[5] Thus, the DSM-5 currently acknowledges APS as a potential disorder and provides clinicians and researchers a mechanism to recognize a clinically meaningful attenuated form of psychosis that is associated with risk for progression to full psychosis. Despite ongoing debate about the inclusion of APS in the DSM-5,[6],[7] including the Forum commentary by Dr. Xu and colleagues[8], there has been substantial validating evidence for the construct.[9],[10]Approximately 64% of persons meeting criteria for APS do not develop a psychotic disorder within three years of the onset of APS.[11] They are, nevertheless, at risk for a variety of mental health problems that merit clinical monitoring and management including, but not limited to, subthreshold psychotic symptoms, depression, anxiety, attention-deficit and hyperactivity disorder (ADHD), cognitive deficits, impaired social functioning, family stress, substance abuse, exposure to trauma, and lower quality of life. Moreover, the pattern of distress and symptomatology experienced by individuals with APS is distinct both from that seen in community members who do not seek treatment and from non-APS treatment seekers. Thus the clinical identification of APS is not only important as a method for identifying persons at high-risk of subsequent psychosis; it is also a broad marker for identifying individuals who merit active treatment to address a variety of psychological symptoms.[11],[12],[13]Much more high-quality research among individuals with APS is needed to characterize the level of morbidity and to identify the predictors of outcome. DSM-5 already provides a diagnostic label that includes APS (Other Specified Schizophrenia Spectrum and Other Psychotic Disorders), but the subsequent definition of a specific APS diagnostic category (currently under discussion for the forthcoming DSM-5.1) could greatly facilitate research on APS by promoting improved communication and integration of knowledge between the increasing number of expert centers conducting research on APS or other high-risk syndromes. For instance, prior to the publication of the DSM-5, characteristic symptoms of ‘clinical high-risk’ (CHR) were not well captured under any existing DSM category, indicating the need and potential utility of defining such a category. Using vignette methodology in a study of community-based mental health providers, we found that when given a list of DSM-IV-TR diagnoses the majority of providers diagnosed our validated APS vignette as having a full psychotic illness and 69% of them recommended treatment with antipsychotic medication, a treatment that is explicitly not recommended for this population.[14],[15] This work suggests that over-diagnosis and consequent over-treatment is likely common for patients with APS; having a specific APS category in DSM-5 should facilitate more accurate classification and, hopefully, more appropriate treatment for this important population.Another important advantage of the recognition of APS in the DSM-5 involves workforce development. Despite the fact that at least 50% of people who ultimately develop schizophrenia report attenuated psychotic symptoms in adolescence, psychosis tends to be considered an “adult” disorder. In a recent pilot poll of mental health providers, we found that providers who self-label as child or adolescent-focused providers reported being relatively unfamiliar with psychosis, while those who self-label as adult-focused providers (who were less comfortable working with youth) report more familiarity with psychosis.[16] These findings suggest that the current mental health workforce is not effectively trained to both be sensitive to early signs of psychosis, and to be aware of the developmental needs of adolescents. The APS diagnosis, which primarily occurs among adolescents and young adults, has the potential to shift attention to psychotic and pre-psychotic symptoms in a younger age range and, thus, lead to increased training and sensitivity to risk for psychosis among youth-oriented mental health providers. We have found that even brief training sessions can increase the understanding and awareness of risk signs for psychosis among youth-focused providers.[17]A potential strategy that may help improve the reliability of the APS diagnosis is the use of pre-screening measures. Our research has shown that a variety of methods designed to assess APS symptoms, including both self-report measures and family member-reported measures, are effective for improving diagnostic reliability in real-world clinical settings.[18],[19],[20],[21] Further, when these measures are used to determine whether or not to refer an individual to a specialized clinic for early psychosis, the positive predictive values for future psychosis have ranged from 39 to 53%. Although untested at this point, these results suggest that pre-screened individuals who then meet APS criteria are a subgroup of persons with APS who are at elevated risk of subsequent psychosis. Screening may identify more individuals in need of APS-tailored care, both among those who do and do not subsequently transition to full psychosis.[22].The inclusion of APS in DSM-5’s Section 3 (for conditions meriting further study) and under the Other Specified Schizophrenia Spectrum and Other Psychotic Disorders diagnosis is an important advance for the field of psychiatry. Given the unique characteristics of people who meet criteria for APS and the growing literature on the clinical benefits of providing services to individuals who meet these criteria, the APS diagnosis serves an important, and previously missing, role in psychiatry. Use of the APS category has the potential to identify, diagnose, and appropriately treat individuals who were likely misclassified and mismanaged in the past. Furthermore, recognition of APS as a common condition among adolescents should promote expanded training about psychosis and attenuated psychosis among clinicians who primarily provide services to children and youth. Only some of the individuals with APS subsequently develop psychosis (i.e., there are many ‘false positives’), but all of them have existing clinical needs – regardless of subsequent conversion. The formal recognition of APS in DSM-5 will facilitate the research needed to identify and meet those needs.