Staging bipolar disorder: clinical, biochemical, and functional correlates
Article first published online: 15 MAR 2014
© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Acta Psychiatrica Scandinavica
Volume 129, Issue 6, pages 437–444, June 2014
How to Cite
Staging bipolar disorder: clinical, biochemical, and functional correlates., , , , , , , , , .
- Issue published online: 12 MAY 2014
- Article first published online: 15 MAR 2014
- Manuscript Accepted: 24 FEB 2014
- Instituto de Salud Carlos III, Spanish Ministry of Economy and Competiveness. Grant Number: CM12/00062
- Río Hortega Contract
- Eli Lilly
- Stanley Medical Research Institute
- Bristol-Myers Squibb
- Forest Research Institute
- early stage;
- late stage;
- bipolar disorder;
- interleukin 6;
- functional outcome
There are several models of staging in bipolar disorder (BD), but none has been validated. The aims of this study were to empirically investigate clinical variables that may be useful to classify patients in clusters according to stage and study the association with biomarkers as biological validators.
This was a historical cohort study. Patients (n = 115) diagnosed with BD and not in an acute episode and first-degree relatives of patients diagnosed with BD (n = 25) were recruited. Sociodemographic, clinical, and functional data were collected. Serum cytokines, brain-derived neurotrophic factor, and biomarkers of lipid and protein oxidation were assessed. Cluster analysis was carried out to build a model of staging, and logistic regression was conducted to study associations between the model and biomarkers.
Cluster analysis divided the sample into two equitable groups, denominated early and late stage, with empirical cutoffs for the Functioning Assessment Short Test score, number of episodes, age at onset of the disorder, and time elapsed since first episode. In the logistic regression, IL-6 was associated with late stage (P = 0.029).
This study supports that clinical, functional, and biochemical variables may help to define a classification of staging in BD.