title: First-ever stroke following hip replacement surgeries: a large population-based survey.
abstract: OBJECTIVE
  This study was designed to determine the prevalence, subtypes and risk factors of first-ever stroke following hip replacement (HR) in a large population of Taiwan.
  
  
  METHODS
  Using the National Health Insurance system of Taiwan, we identified patients undergoing HR from 2000 to 2011 and randomly selected 4 : 1 age- and sex-matched controls for each HR patients. The index date for HR patients was defined the date for HR. All study subjects were followed from the index date until stroke occurred at admission. T-test and chi-square test were used for continuous and categorical variables, respectively. The hazard ratios of risk factors were determined with Cox proportional hazard regression model.
  
  
  RESULTS
  A total of 3604 HR patients and 14 394 controls were enrolled. In comparison with controls, patients undergoing HR had a significantly higher incidence of comorbidities (i.e. atrial fibrillation, hypertension, diabetes) and consumed more medications (i.e. antihypertension, antidiabetes, nonsteroid anti-inflammatory drugs and anticoagulants) before surgery. The HR patients had a significant higher incidence of first-ever stroke, especially for those aged over 65. (Hazard ratio: 1·33, 95% confidence interval: 1·12-1·58) The significantly higher risk for first-ever stroke occurred within 3 months and ≥ 1 year after HR. The incidence rate of ischaemic stroke is about five times than that of haemorrhagic stroke.
  
  
  CONCLUSIONS
  Our study identifies multiple risk factors that cause cerebrovascular complications after HR, which is vital in creating treatment plans to prevent for said problems.
authors.affiliation: Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan.|National Yang-Ming University, Taipei, Taiwan.
authors.forename: Chia-To
authors.initials: CT
authors.lastname: Wang
authors.affiliation: UC Berkeley Mishler Lab Undergraduate Researcher, Intended B.S. Molecular and Cell Biology, University of California, Berkeley, CA, USA.
authors.forename: Eric
authors.initials: E
authors.lastname: Chuang
authors.affiliation: National Yang-Ming University, Taipei, Taiwan.|Department of Neurology, Taipei Veterans General Hospital, Taipei, Taiwan.
authors.forename: Der-Jen
authors.initials: DJ
authors.lastname: Yen
authors.affiliation: Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei, Taiwan.|National Yang-Ming University, Taipei, Taiwan.
authors.forename: Tien-Yow
authors.initials: TY
authors.lastname: Chuang
authors.affiliation: Management Office for Health Data, China Medical University Hospital, Taichung, Taiwan.|College of Medicine, China Medical University, Taichung, Taiwan.
authors.forename: Chih-Hsin
authors.initials: CH
authors.lastname: Muo
authors.affiliation: Graduate Institute of Clinical Medical Science and School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan. d10040@mail.cmuh.org.tw.|Department of Nuclear Medicine and PET Center, China Medical University Hospital, Taichung, Taiwan. d10040@mail.cmuh.org.tw.|Department of Bioinformatics and Medical Engineering, Asia University, Taichung, Taiwan. d10040@mail.cmuh.org.tw.
authors.forename: Chia-Hung
authors.initials: CH
authors.lastname: Kao
mesh_terms: D000328:Adult; D017677:Age Distribution; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000209:etiology; D012307:Risk Factors; D020521:Stroke / Q000209:etiology*; D013624:Taiwan
keywords: First-ever stroke; National Health Insurance system of Taiwan; hip replacement