title: Nationwide cohort study of hip fractures: time trends in the incidence rates and projections up to 2035.
abstract: CONCLUSIONS
  A growing elderly population is expected worldwide, and the burden of hip fractures on health care system will continue to increase. By 2035, there will be a 2.7-fold increase in the number of hip fractures in Taiwan. The study provides quantitative basis for the future distribution of medical resources.
  
  
  BACKGROUND
  Hip fractures have long been recognized as a major public health concern. The study aimed to determine time trends in the incidence of hip fractures and to forecast the number of hip fractures expected in Taiwan up to 2035.
  
  
  METHODS
  A nationwide survey was conducted using data from the Taiwan National Health Insurance Research Database from 2004 to 2011. A total of 141,397 hip fractures were identified, with a mean of 17,675 fractures/year. Annual incidences of hip fractures were calculated and tested for trends. Projections of the incidence rates of hip fractures and bed days associated with hip fractures were calculated using Poisson regression on the historical incidence rates in combination with population projections from 2012 to 2035.
  
  
  RESULTS
  The incidence rates of hip fracture during 2004-2011 were 317 and 211 per 100,000 person-years among women and men, respectively. Over this 8-year period, the age-standardized incidence of hip fracture decreased by 13.4% among women and 12.2% among men. Despite the decline in the age-standardized incidence, the absolute number of hip fractures increased owing to the aging population. The number of hip fractures is expected to increase from 18,338 in 2010 to 50,421 in 2035-a 2.7-fold increase. The number of bed days for 2010 and 2035 was estimated at 161,248 and 501,995, respectively, representing a 3.1-fold increase.
  
  
  CONCLUSIONS
  The socioeconomic impact of hip fractures will be high in the near future. This study provides a quantitative basis for future policy decisions to serve this need.
authors.affiliation: Department of Orthopaedic Surgery, Chang Gung Memorial Hospital, No.5, Fuxing Street 333, Guishan Township, Taoyuan, Taiwan.
authors.forename: I-J
authors.initials: IJ
authors.lastname: Chen
authors.forename: C-Y F
authors.initials: CY
authors.lastname: Chiang
authors.forename: Y-H
authors.initials: YH
authors.lastname: Li
authors.forename: C-H
authors.initials: CH
authors.lastname: Chang
authors.forename: C-C
authors.initials: CC
authors.lastname: Hu
authors.forename: D W
authors.initials: DW
authors.lastname: Chen
authors.forename: Y
authors.initials: Y
authors.lastname: Chang
authors.forename: W-E
authors.initials: WE
authors.lastname: Yang
authors.forename: H-N
authors.initials: HN
authors.lastname: Shih
authors.forename: S W-N
authors.initials: SW
authors.lastname: Ueng
authors.forename: P-H
authors.initials: PH
authors.lastname: Hsieh
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D001509:Bed Occupancy / Q000706:statistics & numerical data / Q000639:trends; D015331:Cohort Studies; D005260:Female; D005544:Forecasting; D006306:Health Surveys; D006620:Hip Fractures / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007902:Length of Stay / Q000706:statistics & numerical data; D008297:Male; D008875:Middle Aged; D058866:Osteoporotic Fractures / Q000453:epidemiology*; D017678:Sex Distribution; D013624:Taiwan / Q000453:epidemiology