Number of prior episodes and the presence of depressive symptoms are associated with longer length of stay for patients with acute manic episodes

Background: Few studies have analyzed predictors of length of stay (LOS) in patients admitted due to acute bipolar manic episodes. The purpose of the present study was to estimate LOS and to determine the potential sociodemographic and clinical risk factors associated with a longer hospitalization. Such information could be useful to identify those patients at high risk for long LOS and to allocate them to special treatments, with the aim of optimizing their hospital management. Methods: This was a cross-sectional study recruiting adult patients with a diagnosis of bipolar disorder (Diagnostic and Statistical Manual of Mental Disorders, 4th edition, text revision (DSM-IV-TR) criteria) who had been hospitalized due to an acute manic episode with a Young Mania Rating Scale total score greater than 20. Bivariate correlational and multiple linear regression analyses were performed to identify independent predictors of LOS. Results: A total of 235 patients from 44 centers were included in the study. The only factors that were significantly associated to LOS in the regression model were the number of previous episodes and the Montgomery-Åsberg Depression Rating Scale (MADRS) total score at admission (P < 0.05). Conclusions: Patients with a high number of previous episodes and those with depressive symptoms during mania are more likely to stay longer in hospital. Patients with severe depressive symptoms may have a more severe or treatment-resistant course of the acute bipolar manic episode.This study was sponsored by AstraZeneca Spain. MM-C has received honoraria for speaking for Eli Lilly, Lundbeck, Pfizer, Janssen-Cilag, Servier, Esteve, and Novartis, and he has received a research grant from Novartis. AG-P has received grant support, acted as consultant, or given presentations for the following pharmaceutical companies: Almirall, AstraZeneca, Bristol-Myers-Squibb, Otsuka, Eli Lilly, Glaxo-Smith-Kline, Janssen-Cilag, Sanofi-Aventis, Lundbeck, Novartis, Organon, Schering-Plough, Spanish Ministry of Science and Innovation, Department of Health of the Basque Government, University of the Basque Country and Pfizer. JLG was an employee of AstraZeneca Spain when the study was designed, the data were collected, and the statistical analysis was carried out. JB does not have any conflicts of interest to declare. JM is an employee of AstraZeneca Spain. EV received honoraria as member of the EMBLEM Advisory Board from Eli Lilly and Co, and has also received grants unrelated to this study, acted as consultant, or served on advisory boards for the following entities: Astra-Zeneca, Bristol- Myers-Squibb, Eli Lilly, Forest Research Institute, Glaxo-Smith-Kline, Janssen- Cilag, Jazz, Merck-Sharpe & Dohme, Novartis, Organon, Otsuka, Pfizer, Sanofi, Servier, Seventh European Framework Programme (ENBREC), Shering-Plough, Spanish Ministry of Science and Innovation, United Biosource Corporation, and Wyeth