Risk factors for hip fracture among institutionalised older people.

BACKGROUND: risk factors for hip fracture in community-dwelling individuals have been extensively studied, but there have been fewer studies of institutionalised older people.
METHODS: a total of 1,894 older people (1,433 females, 461 males; mean age 86 years, SD 7.1 years) were recruited from 52 nursing homes and 30 intermediate-care nursing care facilities in Australia during March 1999 and February 2003. We assessed clinical risk factors for hip fracture and skeletal fragility by calcaneus broadband ultrasound attenuation (BUA) at baseline and then followed up for fracture for 4 years. Hip fractures were validated by x-ray reports. Survival analysis with age as a time-dependent covariate was used to analyse the data.
RESULTS: during a mean follow-up period of 2.65 years (SD 1.38), 201 hip fractures in 191 residents were recorded, giving an overall hip fracture incidence rate of 4.0% per person year (males 3.6% and females 4.1%). Residents living in intermediate-care hostels had a higher crude hip fracture rate (4.6% vs. 3.0%) than those living in high-care nursing homes. In multivariate analysis, an increased risk of hip fracture was significantly associated with older age, cognitive impairment, a history of fracture since age 50, lower body weight, longer lower leg length and poorer balance in intermediate-care hostel residents, but not with lower BUA.
CONCLUSIONS: institutionalised older people, who are at a higher risk of hip fracture than community-dwelling individuals, have differences in some risk factors for hip fracture that should be considered in targeting intervention programs.