Six-fold increased risk of hip fracture in older Australians (≥60 years) with dementia

The objectives were: (1) to estimate the prevalence of dementia in older people with hip fracture (HF) and (2) to evaluate the significance of dementia and residential care as risk factors for HF in the Australian Capital Territory (ACT), Australia.

We performed a prospective study of 555 consecutive patients (≥60 years) with HF (mean age 82.6±7.9 (SD) years; 74.2% women) within 162,608 person-years of observation. The main predictor variables of HF were, pre-fracture diagnosed dementia of any type and residential status. ACT population estimates and age- and gender-specific prevalence rates of dementia in the ACT population were used to calculate the relative risk of HF in demented people.

Of those with HF, 176 (31.7%) were diagnosed with dementia prior to the fracture. Multiple logistic regression analysis revealed that dementia in HF patients was associated with history of stroke (OR=2.2; 95% CI 1.2–4.0; p=0.008), residential care (OR=6.7; 95% CI 4.5–10.2; p=0.001) and older age (OR=1.03; 95% CI 1.0–1.1; p=0.036). The overall relative risk (RR) for HF in persons with dementia was 6.3 (95% CI 5.1–7.1) times higher than in those without pre-fracture dementia, and the RR in the young-old (60–79 years) with dementia was higher than in the old-old (≥85 years). The RR of HF for demented persons living in long-term residential care facilities compared to the non-demented age-matched community-dwelling population was 16.3 (95% CI 14.4–18.2; p=0.001).

This study demonstrated a high prevalence of demented people among HF patients and a 6.3-fold risk for HF in older persons with dementia. This risk is almost 2.6 times greater in demented people living in residential care. These data may be useful in health policy decisions and strongly support development of targeted HF prevention strategies, planning and allocation of resources and prioritisation of prevention efforts toward those with dementia, especially in residential care.