اضطراب جدایی در دوران بزرگسالی: بعدی یا قطعی؟

Recent evidence suggests that a clinical form of separation anxiety can be observed in adults. An important question of relevance to defining the construct of adult separation anxiety is whether there is discontinuity between that constellation and other forms of anxiety. In the present study, 2 taxometric procedures—Mean Above Minus Below a Cut and Maximum Eigenvalue—were used to assess whether adult separation anxiety conformed primarily to a categorical or a dimensional pattern. The data were derived from a separation anxiety symptom questionnaire completed by 840 consecutive adult patients attending an anxiety disorders clinic. Although some results of the analysis were ambiguous, the overall findings suggested a dimensional pattern. The relevance of the finding to the status of adult separation anxiety is discussed.

Extensive research has been devoted to the study of juvenile-onset separation anxiety disorder (JSAD) [1] and [2], a common disorder in the community [3] and [4] and the most prevalent diagnosis presenting to childhood anxiety clinics [5]. The developmental trajectory of JSAD however remains unclear [6], [7] and [8], with some investigations suggesting that it creates risk specifically to panic disorder in adulthood [9], whereas more recent studies have indicated that JSAD may be a generic risk factor to a range of adult anxiety subcategories [10]. A third possibility, suggested by Manicavasagar and Silove [11], is that JSAD may persist, manifesting as an adult form of the disorder (the continuity hypothesis). That trajectory would be analogous to that of other early-onset anxiety disorders, such as social phobia, that commonly extend from adolescence into adulthood. The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) [12], although classifying JSAD as a disorder of childhood and stipulating onset before 18 years of age, allows for the disorder to continue into later life. Nevertheless, until recently [13], the custom has been to exclude the putative subcategory of adult separation anxiety disorder (ASAD) from consideration in both epidemiologic [14] and [15] and clinical [16] studies focusing on the adult subtypes of anxiety. Yet there is growing evidence suggesting that separation anxiety can occur in later life in a form that seems equivalent to JSAD, although symptoms are modified somewhat by development [17]. The primary anxiety associated with ASAD is the fear of actual or possible separation from close attachment figures and a consequent preoccupation with the safety and whereabouts of those persons. Anxieties extend beyond parents to include intimate partners and children [11] and [17]. Whereas the criteria for JSAD highlight somatic symptoms such as nausea and stomachaches [12], such physical complaints seem to be less prominent in adults who instead exhibit more cognitive and emotional symptoms [11]. Moreover, adulthood presents different opportunities for those with separation anxiety to deal with their fears, for example, by making frequent phone calls, by adhering to rigid routines that ensure frequent contact with attachment figures, or by talking excessively as a means of lengthening contact time with key others [17]. An important question, nevertheless, is whether the proposed novel category of ASAD should be accorded a separate status equivalent to established subtypes of anxiety such as panic disorder and social phobia. Several factors determine the addition of disorders to the classification system, including inter alia, the consistent clustering of symptoms, a discriminating risk factor profile, family aggregation, a distinct period of onset, a predictable course and outcome, and a demonstrated response to specific interventions [18] and [19]. If the putative disorder is clearly demarcated from related symptom patterns by conforming to a categorical construct, that observation may add to other evidence supporting the distinctiveness of the syndrome (although the converse is not the case, that is, a dimensional pattern does not on its own preclude recognition of a disorder as warranting a separate status in the diagnostic system). The present study aims to examine whether symptoms of adult separation anxiety conform to a categorical or dimensional pattern. The present study builds on existing research undertaken by our group [17], [20], [21] and [22] that has sought to examine the phenomenology, developmental trajectory, and familial clustering of adult separation anxiety. In pursuing these investigations [8], [11] and [17], we have established 2 methods for assessing the putative category of ASAD: a structured interview [17] and a self-report questionnaire [23], each containing the same items. Items were derived from modified JSAD criteria and from clinical observations of patients thought to have the adult disorder. The structured interview allows trained clinicians to make a global clinical judgment about the presence or absence of ASAD, with past studies yielding high levels of interrater reliability [17] and [22]. The Adult Separation Anxiety Self-Report Questionnaire (ASA-27), previously called the Adult Separation Anxiety Self-Report Checklist [21], is rated directly by respondents on a 4-point symptom frequency scale. Receiver operation characteristic analysis has shown a close concordance between the structured interview and the checklist [23]. Demonstrating continuities between a recognized childhood disorder (JSAD) and a putative adult form (ASAD) offers support for the nosologic status of the latter. In a community sample, Manicavasagar et al [17] found that most persons with ASAD reported high levels of separation anxiety in their early years. A subsequent study undertaken at an anxiety clinic (N = 70) [21] confirmed this developmental association, with those classified as having ASAD reporting differentially high levels of early separation anxiety compared with other anxiety patients. A third, community-based study of adults with histories of school anxiety [8] showed a close association between ASAD and past JSAD. Those reporting past JSAD had an 8-fold risk of being assigned a current diagnosis of ASAD. Since psychiatric disorders often cluster within families, demonstrating a pattern of aggregation adds indirect evidence in support of the status of a disorder. A study undertaken at a juvenile anxiety clinic [22] found that parents of children with JSAD had an 11-fold increased risk of ASAD but no higher rate of other anxiety disorders when compared with parents of children with other juvenile anxiety disorders. The results suggest a high level of specificity in the family clustering of adult and juvenile separation anxiety. As yet, however, no studies have assessed whether adult separation anxiety conforms to a categorical or dimensional pattern, that is, whether there is a “point of rarity” demarcating that pattern from other forms of anxiety. The present study aimed to examine this issue by applying taxometric analyses to a large data set obtained from an anxiety clinic. Taxometric techniques were formulated by Meehl and colleagues [24], [25] and [26] to determine the latent structure of a particular phenomenon. Specifically, the analysis applied herein aimed to assess whether the latent structure of ASAD is best represented as an extreme point on a continuum of separation anxiety (ie, a continuous/dimensional structure) or whether the symptom pattern clearly polarized respondents into 2 groups, hence indicating a taxonic structure.