title: Risk factors for the second contralateral hip fracture in elderly patients: a systematic review and meta-analysis.
abstract: OBJECTIVE
  To achieve a quantitative and comprehensive conclusion concerning the risk factors for the second contralateral hip fracture in elderly patients with initial hip fractures.
  
  
  METHODS
  This search was applied to Medline, Embase, Cochrane central database (all up to April 2014).
  
  
  METHODS
  All the studies on bilateral hip fractures in elderly patients published in English were reviewed and qualities of included studies were assessed using the Newcastle-Ottawa Scale. All the data were carefully and independently abstracted by two reviewers, any disagreement was settled by discussion. Data was pooled and a meta-analysis completed.
  
  
  RESULTS
  A total of 13 case-control studies were identified for the meta-analysis. The significant risk factors were female (odds ratio (OR), 1.30; 95% confidence interval (CI), 1.02-1.64), living in institutions (OR, 2.53; 95% CI, 1.33-4.85), osteoporosis (OR, 10.02; 95% CI, 5.41-18.57), low vision (OR, 2.09; 95% CI, 1.06-4.12), dementia (OR, 2.02; 95% CI, 1.54-2.65), dizziness (OR, 2.87; 95% CI, 1.42-5.87) cardiac diseases (OR, 1.33; 95% CI, 1.00-1.78) and respiration diseases (OR, 2.58; 95% CI, 1.22-5.47). No significant difference was found in admission age between patients with the unilateral hip fracture and the first hip fracture of bilateral hip groups (standardized mean difference, 0.02, 95% CI, -0.30 to 0.35].
  
  
  CONCLUSIONS
  Patients involved with female, living in institutions, osteoporosis, low vision, dizziness, dementia, respiration diseases and cardiac diseases were at risk for a second contralateral hip fracture after the initial hip fracture.
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China.
authors.forename: Song
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China.
authors.forename: Yanbin
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Sun
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China.
authors.forename: Jiaxiang
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Department of Orthopaedic Surgery, The 3rd Hospital of Hebei Medical University, Shijiazhuang, People's Republic of China Key Laboratory of Biomechanics of Hebei Province, Shijiazhuang, People's Republic of China dryzzhang@126.com.
authors.forename: Yingze
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D015897:Comorbidity; D016206:Databases, Bibliographic; D003704:Dementia / Q000453:epidemiology; D004244:Dizziness / Q000453:epidemiology; D005163:Factor Analysis, Statistical; D005260:Female; D006331:Heart Diseases / Q000453:epidemiology; D006620:Hip Fractures / Q000453:epidemiology* / Q000209:etiology; D006801:Humans; D015994:Incidence; D007297:Inpatients / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000150:complications* / Q000453:epidemiology; D012112:Residential Facilities / Q000706:statistics & numerical data; D012120:Respiration Disorders / Q000453:epidemiology; D012307:Risk Factors; D017678:Sex Distribution; D014786:Vision Disorders / Q000453:epidemiology
keywords: Bone; factor analysis; fracture