title: Association between non-compliance with psychiatric treatment and non-psychiatric service utilization and costs in patients with schizophrenia and related disorders.
abstract: BACKGROUND
  The relationship between medication non-compliance in patients with schizophrenia and related disorders, and increased psychiatric service utilization and costs are well documented; however, non-psychiatric service utilization and costs are not. Therefore, we investigated the association of non-compliance with psychiatric treatment and the utilization and costs of non-psychiatric services.
  
  
  METHODS
  Data on South Korean individuals with a lifetime diagnosis of schizophrenia or a related disorder, who were treated in a psychiatric clinic at least twice during 2011, were selected among national data collected for the Health Insurance Review and Assessment Service-National Patients Sample between January 1, 2011 and December 31, 2011. The sample was divided into two overlapping groups with two different classifications of patterns of medication prescription refills: (1) adherent versus non-adherent group, and (2) persistent versus non-persistent group. A matching method was used to remove the effects of different follow-up durations and insurance system on medical service utilization and costs. The final sample for analysis consisted of data from 5,548 individuals in the adherent versus non-adherent group and 3,912 in the persistent versus non-persistent group. Comparisons of the psychiatric and non-psychiatric service utilizations were made between the groups.
  
  
  RESULTS
  The number of psychiatric service utilizations were significantly lower in the non-adherent than the adherent group. They were also significantly lower in the non-persistent group than the persistent group. The number of non-psychiatric service utilizations was significantly higher in the non-adherent group. They were also significantly higher in the non-persistent group than the persistent group. All psychiatric costs per person during the study period were lower in the non-adherent than the adherent group, and lower in the non-persistent than the persistent group. All non-psychiatric costs per person were higher in the non-adherent than the adherent group, and higher in the non-persistent than the persistent group.
  
  
  CONCLUSIONS
  Non-adherence to psychiatric treatment by patients with schizophrenia and related disorders was associated with higher medical service utilization and increased personal and societal medical costs.
authors.affiliation: Department of Psychiatric rehabilitation, Bugok National Hospital, Changnyung, Kyungnam, Republic of Korea.
authors.forename: Soohyun
authors.initials: S
authors.lastname: Joe
authors.affiliation: Department of Psychiatry, University of Ulsan College of Medicine, Asan Medical Center, 88, Olympic-ro 43-Gil, SongPa-Gu, Seoul, 05505, Republic of Korea. ljssmh@gmail.com.
authors.forename: Jung Sun
authors.initials: JS
authors.lastname: Lee
mesh_terms: D000328:Adult; D000553:Ambulatory Care / Q000191:economics*; D014150:Antipsychotic Agents / Q000191:economics*; D011307:Drug Prescriptions / Q000191:economics; D005260:Female; D017048:Health Care Costs / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D005791:Patient Care / Q000191:economics*; D012189:Retrospective Studies; D012559:Schizophrenia / Q000188:drug therapy / Q000191:economics*; D055815:Young Adult; D016903:Drug Monitoring
chemical_list: D014150:Antipsychotic Agents
keywords: Medical costs; Medication adherence; Medication compliance; Medication persistence; Psychiatry; Service costs