Research paperThresholds for severity, remission and recovery using the functioning assessment short test (FAST) in bipolar disorder
Introduction
Randomized controlled trials (RCTs) in psychiatry rely on clinician-rated instruments to study the treatment efficacy. Traditionally, the outcomes in RCTs have been defined in a context of reduction of symptoms (response/partial response/non response). However, in the last years, the focus has also moved from clinical remission to functional recovery (Vieta and Torrent, 2016). Hence, the most meaningful endpoint is no longer mere improvement, nor remission, but recovery. Indeed, functional recovery is, for some patients, a difficult goal, even if they have reached clinical remission. One of the major issues associated with functional recovery is the lack of consensus on the terminology and standards used to measure it (Harvey, 2006). Indeed, there exist many different tools to assess psychosocial functioning in psychiatry: the WHODAS 2.0 (WHO, 2001), now endorsed by the APA and the DSM-5 as the preferred measure of functional impairment (Garin et al., 2010, Ayuso-Mateos et al., 2013); the LIFE-RIFT (León et al., 1999) or the MSIF (Jaeger et al., 2003), among others. However, the FAST is the first scale that focuses on the principal problems faced by patients with Bipolar Disorder (BD) (Rosa et al., 2007). There is also a great heterogeneity in functional outcome when assessing patients with BD as reported in literature (Solé et al., 2018, MacQueen et al., 2001, Reinares et al., 2013). In this line, a recent study has classified the patients into different groups according to the impairment shown in different domains of functioning in the FAST scale by using an exploratory cluster analysis (Solé et al., 2018). Three different patterns were observed: one group with no significant impairment in any of the assessed domains; a second group with mild impairment in different domains but severe impairment in occupational functioning. Finally, the last group included patients with severe impairment in most of the assessed domains. The results of this study highlight the heterogeneity observed in functional outcome of patients suffering from BD, and the need to classify the degree of impairment more accurately. The categorization provided in that study is useful but it might not be the optimal way to measure severity in functional impairment, especially if the patients are enrolled in RCTs. Since RCT use total scores derived from observer rating scales (i.e.: Hamilton Depression Rating Scale (HAM-D) or Young Mania Rating Scale (YMRS), a severity gradation for functional outcome in BD is urgently needed. This classification is essential to assess the efficacy of new pharmacological and psychological treatments aiming at improving (direct or indirectly) psychosocial functioning.
The validation of the FAST scale in 2007 did not include cut-offs for severity gradation in psychosocial functioning (Rosa et al., 2007). A single cut-off was stablished to differentiate between impaired and non-impaired patients. Moreover, in that study, the concurrent validity of the FAST was studied considering the GAF-F. Given this previous experience with both scales, and that both the GAF-F (DSM-IV 4th edition, 1994) and the FAST assess functional outcome, it is important to analyze their empirical correlation and to establish corresponding cut-off values for severity gradations of the FAST scale (e.g: no impairment, mild, moderate, and severe) taking into account the GAF-F scores. Therefore, we analyzed data of GAF-F and FAST ratings from a sample of euthymic patients with bipolar I and II with the objective to establish different cut-off scores for the FAST scale.
Section snippets
Participants
Data for this analysis were pooled from a previous study assessing the validity of the FAST scale (Rosa et al., 2007). The original sample comprised a total of 101 patients with BD including both euthymic and acute patients that were recruited at the Hospital Clinic of Barcelona. In the original study, patients were interviewed with the Structured Clinical Interview for the DSM-IV TR criteria (First et al., 1997) and were administered several clinical and functional scales. Regarding
Demographic and clinical characteristics of the sample
A total of 65 patients out from the initial sample met the criteria of euthymia established for this analysis. The mean age of patients was 46 years old (SD = 13.5). Forty-six per cent of the total sample (n = 30) were female. Patients presented a mean of HAM-D score of 1.6 (S.D = 2.4) and a mean of YMRS total score of 0.6 (SD = 1.3). Approximately, one third of the sample (32.3%; n = 21) were married or living as a couple.
Patients presented a mean of 6 depressive episodes (Mean = 6.4;
Discussion
According to the present results we propose different cut-off values for the FAST scale in order to differentiate categories of severity of functional impairment:
a) No impairment: from 0 to 11 in the FAST total score. Patients in this category present good functioning in all areas, they live independently, they work and they have a meaningful social engagement. For patients who showed impaired functioning in the past, means recovery.
b) Mild impairment: from 12 to 20 in the FAST total score.
Role of funding source
This study was supported by the Instituto de Salud Carlos III, the CIBER of Mental Health (CIBERSAM), the Spanish Ministry of Economy, Industry and Competitiveness (PI15/00283, PI15/00330/PI16/00187) integrated into the Plan Nacional de I + D + I y cofinanciado por el ISCIII-Subdirección General de Evaluación y el Fondo Europeo de Desarrollo Regional (FEDER).
Contributors
Rosa AR, Martínez-Arán A and Vieta E contributed to the design of the study and manuscript preparation.
Bonnín CM, Reinares M, Valentí M, Jimenez E and Solé B contributed to data analysis and manuscript preparation.
Montejo L contributed with literature review.
Conflicts of interest
Dr. Martinez-Arán has served as speaker or advisor for the following companies: Bristol-Myers Squibb, Otsuka, Lundbeck and Pfizer.
Dr. Vieta has received grants, CME-related honoraria, or consulting fees from AB-Biotics, Alexza, Almirall, Allergan, AstraZeneca, Bristol-Myers Squibb, Cephalon, Dainippon SumigtomoPharma, Eli Lilly, Ferrer, Forest Research Institute, Gedeon Richter, GlaxoSmith-Kline, Janssen, Janssen-Cilag, Jazz, Johnson & Johnson, Lundbeck, Merck, Novartis, Organon, Otsuka,
Acknowledgments
The authors would like to thank the support of the Spanish Ministry of Economy, Industry and Competitiveness; the CIBER of Mental Health (CIBERSAM); the Secretaria d'Universitats i Recerca del Departament d'Economia i Coneixement (2017 SGR 1365) and the CERCA Programme / Generalitat de Catalunya. Finally, Dr. Bonnín would like to thank the Departament de Salut de la Generalitat de Catalunya for the PERIS grant (SLT002/16/00331).
References (35)
- et al.
Subthreshold symptoms in bipolar disorder: impact on neurocognition, quality of life and disability
J. Affect. Disord.
(2012) - et al.
Spanish version of a scale for the assessment of mania: validity and reliability of the young mania rating scale
Med. Clin. (Barc.)
(2002) - et al.
Asenapine prescribing patterns in the treatment of manic in- and outpatients: results from the MANACOR study
Eur. Psychiatry
(2015) - et al.
Moderate and severe depression. Gradations for the montgomery-asberg depression rating scale
J. Affect. Disord.
(2000) - et al.
Towards a clinical staging for bipolar disorder: defining patient subtypes based on functional outcome
J. Affect. Disord.
(2013) - et al.
Functional impairment and disability across mood states in bipolar disorder
Value Heal.
(2010) - et al.
Clinical staging and serum cytokines in bipolar patients during euthymia
Prog. Neuropsychopharmacol. Biol. Psychiatry
(2017) - et al.
A pilot study of a combined group and individual functional remediation program for patients with bipolar I disorder
J. Affect. Disord.
(2016) Global assessment of functioning (GAF): properties and frontier of current knowledge
Ann. Gen. Psychiatry
(2010)Guidelines for rating global assessment of functioning (GAF)
Ann. Gen. Psychiatry
(2011)