title: The risks of major osteoporotic fractures in patients with schizophrenia: a population-based 10-year follow-up study.
abstract: OBJECTIVE
  The aim of the study is to explore the incidence and the risks associated with major osteoporotic fractures, all-cause mortality with osteoporotic fractures and the effect of the psychiatric drug exposure in patients with schizophrenia during a 10-year follow-up period.
  
  
  METHODS
  Two nationwide cohorts were selected from the Taiwan National Health Insurance Research Database (NHIRD) consisting of 30,335 patients with schizophrenia (age ≥ 40 years) and 121,340 age- and sex-matched control participants without schizophrenia. The psychiatric proportion of days covered (PDC) is an indicator of the intensity of drug exposure in patients with schizophrenia. The incidence and risk factors of major osteoporotic fractures were calculated for both cohorts. Additionally, the patient survival rate after major osteoporotic fractures was also calculated.
  
  
  RESULTS
  During a 10-year follow-up period, 1677 (5.53%) schizophrenia and 4257 (3.51%) control subjects had major osteoporotic fractures (P < 0.001). The schizophrenia patients with a PDC > 0.1 showed a significantly higher incidence of major osteoporotic fractures than did the non-schizophrenia controls; however, those with a psychiatric PDC ≤ 0.1 did not. After adjustment, the psychiatric PDC was significantly and independently associated with the risk of major osteoporotic fractures except some medical morbidities but the schizophrenia diagnosis was not. In addition, among all 5934 patients with major osteoporotic fracture, the adjusted mortality hazard ratio for psychiatric PDC was 1.92 (95% CI = 1.63-2.26).
  
  
  CONCLUSIONS
  Patients with schizophrenia are at a higher risk for major osteoporotic fractures than the general population and also have a higher mortality rate due to major osteoporotic fractures. These findings may be caused by psychiatric drug use rather than schizophrenia, which suggests that directions can be taken in future studies.
authors.affiliation: Department of Community Psychiatry, Municipal Kaohsiung Kai-Syuan Psychiatric Hospital, Kaohsiung City, Taiwan; Department of Nursing, Meiho University, Ping-Tong County, Taiwan.
authors.forename: Kuan-Yi
authors.initials: KY
authors.lastname: Tsai
authors.affiliation: Department of Otolaryngology, Buddhist Dalin Tzu Chi General Hospital, Chiayi, Taiwan; School of Medicine, Tzu Chi University, Hualian, Taiwan.
authors.forename: Ching-Chih
authors.initials: CC
authors.lastname: Lee
authors.affiliation: Department of Anesthesiology, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Yu-Mei
authors.initials: YM
authors.lastname: Chou
authors.affiliation: Department of Community Psychiatry, Municipal Kaohsiung Kai-Syuan Psychiatric Hospital, Kaohsiung City, Taiwan.
authors.forename: Shih-Pei
authors.initials: SP
authors.lastname: Shen
authors.affiliation: Department of Nursing, I-Shou University, Kaohsiung City, Taiwan.
authors.forename: Chao-Yueh
authors.initials: CY
authors.lastname: Su
authors.affiliation: Department of Addiction Science, Municipal Kaohsiung Kai-Syuan Psychiatric Hospital, Kaohsiung City, Taiwan.
authors.forename: Hung-Chi
authors.initials: HC
authors.lastname: Wu
authors.affiliation: Department of Psychiatry, Chiayi Branch, Taichung Veterans General Hospital, Chiayi, Taiwan.
authors.forename: Min-Wei
authors.initials: MW
authors.lastname: Huang
authors.affiliation: Department of Community Psychiatry, Municipal Kaohsiung Kai-Syuan Psychiatric Hospital, Kaohsiung City, Taiwan.
authors.forename: Jia-Pei
authors.initials: JP
authors.lastname: Shie
authors.affiliation: Department of Community Psychiatry, Municipal Kaohsiung Kai-Syuan Psychiatric Hospital, Kaohsiung City, Taiwan; Graduate Institute of Health Care, Meiho University, Ping-Tong County, Taiwan. Electronic address: f50911.tw@yahoo.com.tw.
authors.forename: Frank Huang-Chih
authors.initials: FH
authors.lastname: Chou
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D018672:Community Health Planning; D005260:Female; D006801:Humans; D015994:Incidence; D007348:Insurance, Health / Q000706:statistics & numerical data; D053208:Kaplan-Meier Estimate; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000150:complications* / Q000453:epidemiology* / Q000401:mortality; D011569:Psychiatric Status Rating Scales; D012306:Risk; D012559:Schizophrenia / Q000150:complications* / Q000453:epidemiology* / Q000401:mortality; D013624:Taiwan
keywords: Major osteoporotic fracture; National Health Insurance Research Database (NHIRD); Proportion of days covered (PDC); Schizophrenia