Exploring the clinical utility of two staging models for bipolar disorder

Abstract

Objective To assess the clinical utility of two staging models for bipolar disorder by examining distribution, correlation, and the relationship to external criteria. These are primarily defined by the recurrence of mood episodes (model A), or by intra‐episodic functioning (model B). Methods In the Dutch Bipolar Cohort, stages according to models A and B were assigned to all patients with bipolar‐I‐disorder (BD‐I; N = 1396). The dispersion of subjects over the stages was assessed and the association between the two models calculated. For both models, change in several clinical markers were concordant with the stage was investigated. Results Staging was possible in 87% of subjects for model A and 75% for model B. For model A, 1079 participants (93%) were assigned to stage 3c (recurrent episodes). Subdividing stage 3c with cut‐offs at 5 and 10 episodes resulted in subgroups containing 242, 510, and 327 subjects. For model B, most participants were assigned to stage II (intra‐episodic symptoms, N = 431 (41%)) or stage III (inability to work, N = 451 (43%)). A low association between models was found. For both models, the clinical markers “age at onset,” “treatment resistance,” and “episode acceleration” changed concordant with the stages. Conclusion The majority of patients with BD‐I clustered in recurrent stage 3 of Model A. Model B showed a larger dispersion. The stepwise change in several clinical markers supports the construct validity of both models. Combining the two staging models and sub‐differentiating the recurrent stage into categories with cut‐offs at 5 and 10 lifetime episodes improves the clinical utility of staging for individual patients.

Clinical profiles of subsequent stages in bipolar disorder: Results from the Dutch Bipolar Cohort

“…Patients were allocated to stage 2 (one mood episode), stage 3a (one mood episode with current residual symptoms), stage 3b (two mood episodes), or stage 3c (multiple recurrent mood episodes). In our previous study on bipolar outpatients, 30 we found clustering in stage 3c of this model, which could be refined by subdividing subjects in this stage into subgroups with a maximum of 5 episodes, 6 to 10 episodes and more than 10 episodes, following cut-off points previously defined by Berk et al and Magalhães et al 33,34 For model B, 24 subjects were assigned to a stage ranging from latent to stage IV, using a predetermined set of items from the Questionnaire for Bipolar Disorder (QBP, 32 Figure 1). Stages I to IV were assigned based on social, occupational, and psychological functioning (Global Assessment of Functioning (GAF) > or ≤ 80), current mood episode (yes or no), employment over the last year (yes or no), work limitations (present or not present), and limitations in functioning (present or not present).…”

“…The influence of clinical characteristics on illness progression may be studied using staging models. In our current study, we are building on two previous studies 29,30 in which we verified the applicability of the two staging models by Berk et al 23 and Kapczinski et al 24 The current study investigates whether clinical profiles based on the characteristics found in previous studies, that is, familial loading, childhood abuse, age at onset, illness duration, comorbid psychiatric disorders, addiction, treatment resistance, and cognitive functioning are associated with illness progression as defined by the model from Berk et al 23…”

Conceptualizing the later stage of bipolar disorder: Descriptive analyses from the ORBIT trial

“…Participants were from the ORBIT RCT (experiencing “later stage” BD, defined as having experienced 10 or more lifetime mood episodes). Importantly, various episodic “cut points” have been used to identify later stage individuals in previous studies, for example, 5 and 10 episodes 1,14,15 . The ORBIT trial from which these data were drawn employed a conservative cut point of 10 episodes to best ensure participants were within later stage.…”

“…The field of BD research is in the midst of attempts to conceptualize progression in BD, with staging models proposed to describe key features and correlates of BD as this progresses. No model of clinical staging in BD has yet been validated with systematic empirical testing, however a number of studies recently have focused on the advancement of staging in BD (eg, 1‐3 ). In line with this, the current study aims to advance the understanding of stage of illness in BD, via an exploration of latent structures underpinning phenomenological experiences, and of clinically meaningful subgroups within the “later stage” of BD.…”

“…Additionally, as noted by Post, 10,12 a more nuanced understanding of each stage of illness will provide a common language for researchers and allow delineation of the complex relationships between the correlates associated with progression, such as accumulating episodes and functional decline. For example, a direct comparison of the dominant BD staging models in classifying individuals resulted in the significant majority of participants classified within the later stages, prompting authors to suggest that further subclassification within the existing definitions of stages would result in greater utility 1 …”