Non-adherence to antipsychotic medication regimens: associations with resource use and costs

Background: Several factors are thought to influence resource use and costs in treating schizophrenia. Aims: To assess the relative impact of non-adherence and other factors associated with resource use and costs incurred by people with schizophrenia. Method: Secondary analyses were made of data from a 1994 national survey of psychiatric morbidity among adults living in institutions in the UK. Factors potentially relating to resource use and costs were examined using two-part models. Results: Patients who failed to adhere to their medication regimen were over one-and-a-half times as likely as patients who did adhere to it to report use of in-patient services. Non-adherence is one of the most significant factors in increasing external service costs, by a factor of almost 3. Non-adherence predicted an excess annual cost per patient of approximately £2500 for in-patient services and over £5000 for total service use. Conclusions: Resource use and costs are influenced by various factors. Medication non-adherence consistently exhibits an association with higher costs. Further important factors are patient needs and the ability of the system to address them.