Irritable versus euphoric mania in psychiatric inpatients: a retrospective study of 251 inpatient episodes

BACKGROUND: Contemporary diagnostic classifications recognise euphoric and irritable mood as core presentations of mania. Whether these predominant affective states reflect distinct clinical profiles or dimensional variations remains unclear, particularly in naturalistic inpatient settings. METHODS: We conducted a retrospective observational study of admissions for manic episodes between 2017 and 2025 at a tertiary psychiatric unit in Porto, Portugal. Eligible admissions had an ICD-10 discharge diagnosis within F30 (manic episode) or F31 (bipolar affective disorder). Electronic records were reviewed to classify predominant mood at admission as euphoric or irritable based on the affective tone documented in the admission psychiatric assessment and early inpatient notes. Several reviewers collected data, with each admission assessed by one reviewer. Demographic, clinical and treatment variables were compared between groups, and variables with potential univariate associations were entered into a multivariable GEE logistic regression model accounting for clustering by patient. RESULTS: A total of 251 inpatient manic episodes were included: 151 (60.2%) predominantly irritable and 100 (39.8%) euphoric. No clear evidence of between-group differences was found in the demographic and clinical characteristics examined, including psychotic symptoms, previous psychiatric admissions and length of stay. No statistically significant differences were observed in the treatment variables examined. CONCLUSIONS: Irritable mood was more frequently documented than euphoric mood in this inpatient sample. No clear evidence of differences was found in the main demographic and clinical characteristics examined; however, the study does not establish equivalence between presentations. Prospective studies using standardised and repeated assessments are needed to determine whether predominant affective tone has independent clinical relevance.