Clinical implications of predominant polarity and the polarity index in bipolar disorder: a naturalistic study.

Bipolar Disorders Program, Department of Psychiatry, Clinical Institute of Neuroscience, Hospital Clínic, University of Barcelona, IDIBAPS, CIBERSAM, Barcelona, Catalonia, Spain
Acta Psychiatrica Scandinavica (Impact Factor: 5.55). 07/2013; DOI: 10.1111/acps.12179
Source: PubMed

ABSTRACT Predominant polarity (PP) is an important variable in maintenance treatment of bipolar disorder (BD). This study aimed at determining the role of polarity index (PI), a metric indicating antimanic versus antidepressive prophylactic potential of drugs, in clinical decision-making.
Two hundred and fifty-seven of 604 (43%) of patients with BD-I or II fulfilled criteria for manic (MPP) or depressive PP (DPP). The PI, representing the ratio of number needed to treat (NNT) for depression prevention to NNT for mania prevention, was calculated for patients' current treatment. MPP and DPP groups were compared regarding sociodemographic, clinical and therapeutic characteristics.
One hundred and forty-three patients (55.6%) fulfilled criteria for DPP and 114 (44.4%) for MPP. Total PI, Antipsychotics' PI, and mood stabilizers PI were higher, indicating a stronger antimanic action, in MPP. MPP presented higher prevalence of BD-I, male gender, younger age, age at onset and at first hospitalization, more hospitalizations, primary substance misuse, and psychotic symptoms. DP correlated with BD-II, depressive onset, primary life events, melancholia, and suicide attempts.
The results confirm the usefulness of the PI. In this large sample, clinical differences among these groups justify differential treatment approach. The PI appears to be a useful operationalization of what clinicians do for maintenance therapy in BD.

  • Source
    Nervenheilkunde 12/2014; 33(12):859-854. · 0.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: BackgroundA large number of patients with bipolar disorder (BD) can be characterized by predominant polarity (PP), which has important implications for relapse prevention. Recently, Popovic et al. (EUR NEUROPSYCHOPHARM 22(5): 339¿346, 2012) proposed the Polarity Index (PI) as a helpful tool in the maintenance treatment of BD. As a numeric expression, it reflects the efficacy of drugs used in treatment of BD. In the present retrospective study, we aimed to validate this Index in a large and well characterized German bipolar sample.Methods We investigated 336 bipolar patients (BP) according to their PP and calculated the PI for each patient in order to prove if maintenance treatment differs according to their PP. Furthermore, we analysed whether PP is associated with demographic and clinical characteristics of BP.ResultsIn our sample, 63.9% of patients fulfilled criteria of PP: 169 patients were classified as depressive predominant polarity (DPP), 46 patients as manic predominant polarity (MPP). The two groups differed significantly in their drug regime: Patients with DPP were more often medicated with lamotrigine and antidepressants, patients with MPP were more often treated with lithium, valproate, carbamazepine and first generation antipsychotics. However, patients with DPP and MPP did not differ significantly with respect to the PI, although they received evidence-based and guideline-driven treatment.Conclusion The reason for this negative finding might well be that for several drugs, which were used frequently, no PI value is available. Nevertheless we suggest PP as an important concept in the planning of BD maintenance treatment.
    BMC Psychiatry 11/2014; 14(1):322. DOI:10.1186/s12888-014-0322-8 · 2.24 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Homeless individuals are an extremely vulnerable and underserved population characterized by overlapping problems of mental illness and substance use. Given the fact that mood disorders are frequently associated with substance use disorders, we wanted to further highlight the role of excitement in substance abuse. Patterns of substance abuse among homeless suffering from unipolar and bipolar depression were compared. The "self-medication hypothesis" which would predict no-differences in substance preference by unipolar (UP) and bipolar (BP) depressed homeless was tested. Homeless individuals from the Vancouver At Home/Chez Soi study were selected for lifetime UP and lifetime BP depression and patterns of substances abused in the previous 12 months were identified with the Mini-International Neuropsychiatric Interview. Differences in substance use between BP-depressed homeless and UP-depressed homeless were tested using Chi-square and logistic regression techniques. No significant differences were observed between UP and BP homeless demographics. The bipolar depressed homeless (BDH) group displayed a higher percentage of Central Nervous System (CNS) Stimulants (χ 8.66, p=0.004) and Opiates (χ 6.41, p=0.013) as compared to the unipolar depressed homeless (UDH) group. CSN Stimulant was the only predictor within the BDH Group (χ(2) 8.74 df 1 p<0.003). Data collected are self-reported and no urinalyses were performed. The results support the hypothesis that beyond the self-medication hypothesis, bipolarity is strictly correlated to substance use; this correlation is also verified in a homeless population. Copyright © 2015 Elsevier B.V. All rights reserved.
    Journal of Affective Disorders 02/2015; 176C. DOI:10.1016/j.jad.2015.01.059 · 3.71 Impact Factor