The Prevalence and Patterns of Combined Psychotropic Polypharmacy among Acute Care Hospitals in Japan

PurposeTo evaluate the prescribing patterns of psychotropic polypharmacy for inpatients of acute care hospitals in Japan.MethodsAdministrative data on 2,639,885 patients admitted to acute care hospitals in Japan between July and December of 2008 were analyzed retrospectively. We defined psychotropic medications as antipsychotics, antidepressants, benzodiazepines, and other sedatives/hypnotics and studied their prescription patterns during the hospitalization of patients with stroke, acute cardiac infarction, cancer, and diabetes mellitus.ResultsAt least one psychotropic drug was prescribed in 35.9% of all cases. Two-drug combinations of antipsychotic drugs were prescribed for stroke patients in 14,615 cases (1.4%), more than 2 in 3,132 cases (0.3%), and 22.4% of cases were prescribed 2 or more psychotropic drugs in addition to antipsychotic drugs. Amongst upper gastrointestinal cancer patients, 7.7% were prescribed a combination of 2 or more drugs, including benzodiazepines. Of the upper gastrointestinal cancer patients who were prescribed benzodiazepines, 20.3% were also prescribed 2 or more psychotropic drugs. Amongst stroke and upper gastrointestinal cancer patients, 36.6% and 35.6%, respectively, were treated with combination therapy using drugs of this class and others.ConclusionThere is a pattern of polypharmacy that combines benzodiazepines and other sedatives/hypnotics with antidepressants or antipsychotic drugs, and this study provides a detailed analysis of this within acute care hospitals. Our results indicate the need for additional research into the efficacy of polypharmacy for inpatients in non-psychiatric settings.