To describe the course and outcome of patients with prospectively defined chronic mania and to identify predictors of treatment non-response.EMBLEM is a 2-year prospective, observational study of bipolar disorder treatment outcomes conducted in 14 European countries. Patients with a manic/mixed episode were assessed and prospectively followed for 1 year. Clinical scales (Clinical Global Impressions-Bipolar Disorder (CGI-BP) overall, mania, and depression; Young Mania Rating Scale (YMRS); and five-item Hamilton Depression Rating Scale (HAM-D-5)) and medication taken were systemically recorded. Treatment adherence and outcome measures were also captured. Chronic mania (non-response) was defined as not achieving more than one point improvement on CGI-BP mania scale during up to 12-month follow-up. The analysis was conducted with 3373 patients who had at least two CGI-BP mania ratings available.A total of 15% of patients fulfilled criteria for chronic mania. Compared to those who responded to treatment, chronic mania was associated with lower severity of mania symptoms at baseline (OR = 0.44, 95% CI 0.37-0.52), shorter duration of current episode before treatment start (OR = 0.71, 95% CI 0.52-0.96), more delusions/hallucinations at baseline (OR = 1.12, 95% CI 1.03-1.22), less socially active (OR = 0.52, 95% CI 0.39-0.70) and greater occupational impairment (OR = 1.54, 95% CI 1.01-2.35) by multivariate statistical analysis.Rather than severity or duration of manic symptoms, factors associated with chronicity in mania are the presence of psychotic symptoms and issues related to social and occupational functioning.