A Trajectory of Long-Term Antipsychotic Medication Dosage in Inpatients with Severe Behavioral and Psychological Symptoms of Dementia: A Retrospective Study.

Introduction: While antipsychotics are often prescribed for behavioral and psychological symptoms of dementia (BPSD), typically on an off-label basis, these medications have serious adverse effects. This study investigated the long-term use of antipsychotics among inpatients with dementia displaying severe BPSD, focusing on how prescriptions change over time.

Methods: Medical charts at Kusakabe Memorial Hospital were retrospectively reviewed from October 2012 to September 2021. The study included patients diagnosed with dementia, admitted for BPSD, and were continuing antipsychotics at 3 months of their admission. Antipsychotic dosages were categorized as high (≥300 mg/d), medium (100-300 mg/d), and low (<100 mg/d) based on chlorpromazine equivalents and tracked until 15 months during hospitalization. Binary logistic regression was used to identify factors associated with dosage reductions between months 3 and 6.

Results: This study involved 188 patients, with an average age of 81.2 years, 67% of whom were diagnosed with Alzheimer's dementia. At 3 months, 15.4% were taking high, 44.1% on medium, and 40.4% on low dosages of antipsychotics. The highest average dosage was observed at 3 months, with a subsequent decrease over time. By the 12th month, 20-30% of patients in all dosage categories had stopped their antipsychotic medication. Significant factors for dosage reduction included higher initial doses (OR 1.003, 95%Cl: 1.001-1.006, P=0.01) and male gender (OR 2.481, 95%Cl: 1.251-4.918, P=0.009).

Discussion: A trajectory of antipsychotic dosage in inpatients with severe BPSD has rarely been reported. This research emphasizes the need for personalized strategies in managing long-term pharmacotherapy for this vulnerable group of patients.