Incidence of hip fractures in the city of Rosario, Argentina

Abstract

In order to determine the incidence of hip fractures (HFx) in the city of Rosario, Argentina, (population, about 900,000), all HFx admitted to 26 medical centers from August 2001 to July 2002 were surveyed. Exclusion criteria were pathological fractures, violent trauma, and fractures in patients living outside urban limits. Demographical data were obtained from the 2001 national census, and the 1991 national census with projections made by the city's statistics department. In the study period, there were 763 HFx in persons aged 50 or older (608 in women and 155 in men). The annual incidence among inhabitants over the age of 50 years was 290 per 100,000 (405 for women, and 137 for men; female/male ratio: 2.96). In the population aged 65 or older, the global incidence was 646 per 100,000 (847 for women, and 343 for men; ratio: 2.47). The mean age (+/-SD) of fractured patients was 79.5+/-9.2 years; median age was 81 years (range: 50-104). Fractured men were younger (76.2+/-9.8 years vs 80.7+/-8.3 years; p <0.0001) and leaner (body mass index [BMI], 24.5+/-3.0 kg/m(2) vs 26.0+/-2.8 kg/m(2); p <0.0001) than fractured women. Most fractured patients either had normal BMI (35%) or were overweight (BMI, 25.1-30.0 kg/m(2); 47.5%). The incidence of fractures increased exponentially with advancing age. Relative risks of HFx (females/males) were calculated for each decade of life; the risk in individuals below the age of 69 was the same in both sexes; in those aged 70 or more the risk was significantly higher among women. Parental origin of fractured patients was mainly Spanish or Italian, reflecting the city's ethnic composition. Most fractures (72.5%) occurred in houses; 20% in apartments, and 7.5% in nursing homes. HFx were trochanteric in 54.4% of cases. Female patients with trochanteric fractures were older than those with cervical ones (80.0+/-9.4 years vs 78.2+/-11.4 years; p <0.01); their weights and BMIs did not differ significantly. The majority of HFx were treated surgically (91.8%); in-hospital mortality was 1.4%. In conclusion, incidence rates of HFx were somewhat higher in Rosario than those found in two other cities of central Argentina one decade earlier.