Body composition and hip fracture type in elderly women

Many observations support the view that there are significant differences between patients sustaining trochanteric fractures and those sustaining cervical fractures of the hip. Our aim was to evaluate the association between soft tissue composition (fat and lean compartments) and the type of hip fracture sustained. Of 120 consecutive women affected by their first hip fracture admitted to our rehabilitation hospital 102 were included in this cross-sectional study. Body composition was assessed by DXA. Body fat mass was lower in the women with trochanteric fracture than in those with cervical fracture (difference between groups: 2.86 kg; 95% CI 0.10-5.61 kg; p=0.042). The percentage of fat was 30.75+/-8.77 (mean+/-SD) versus 34.75+/-7.29 (difference between groups: 4.00; 95% CI 0.84-7.16; p=0.014). In contrast, no meaningful differences in body lean mass were shown between the two groups. Logistic multiple regression showed that fat mass was associated with the type of fracture independently of age, height, weight, time between fracture occurrence and DEXA assessment, comorbidity, number of drugs in use, lean mass and bone mineral content. The logistic regression results were similar when fat percentage was substituted for fat mass. The data show that fat but not lean body mass is associated with the type of hip fracture, contributing to the definition of the differences between patients sustaining cervical or trochanteric fractures. We stress the importance of distinguishing the two types of fracture when clinical or epidemiological studies related to body composition, including those regarding nutrition or physical exercise, are performed.