Creatine kinase associated with aggressive behavior in psychiatric patients.

INTRODUCTION The aim of this study was to investigate to what extent pathological creatine kinase (CK) levels are associated with aggressive behavior in patients admitted to psychiatric facilities. It is based on the assumption that CK activity increases prior to a rise in motor activity and aggressive behavior. It should be noted that this assumption requires additional confirmation in more extended studies. METHOD Over a period of 3 months, the CK levels of 317 psychiatric inpatients were assessed immediately following admission to a secure ward. During the course of the patients' stay (mean: approximately 11 days), their aggressive behavior was independently assessed using the Staff Observation Aggression Scale (SOAS-R). RESULTS A receiver operating characteristic (ROC) analysis estimated an area under the curve (AUC) for subsequent aggressive behavior of 70.7% with a sensitivity of 70.1% and a specificity of 71.2%. When the variables involuntarily admission, lifetime history of aggression and absence of suicide attempts were also taken into account, the AUC was higher at 78.2%. CONCLUSION Despite some methodological shortcomings in the collection of data, the study indicates that it could be useful to measure CK levels at the time of admission because elevated levels may indicate an increased risk of successive aggressive behavior for patients on secure psychiatric wards.