Factors predicting re-hospitalization for inpatients with bipolar mania--A naturalistic cohort.

Patients with bipolar mania often require re-hospitalization, which can be a social-economic burden. This study aimed to investigate the factors affecting time to re-hospitalization for inpatients with acute bipolar mania. In this 6-year naturalistic study we reviewed the charts of inpatients with acute bipolar mania. Potential dichotomous factors including sex, family history of affective disorder, suicide history, and discharge against medical advice, involuntary admission, psychotic features, substance use disorder, and remission at discharge were recorded. Continuous variables including age, age at onset of affective episodes, and number of previous hospitalizations were also recorded. We used survival analysis with a univariate Cox proportional hazard regression model, along with forward multivariate model, to identify the potential factors. Of the 165 patients, 23% achieved symptomatic remission at discharge. In the forward Cox model, psychotic features, discharge against medical advice and higher number of previous hospitalizations were significant risk factors for re-admission. Remission at discharge was significantly associated with preventing re-hospitalization. We identified several predictors for re-hospitalization among inpatients with bipolar mania. Further studies are needed in other real-world settings to validate our results.