Body mass index as a prognostic factor for fracturing of the proximal extremity of the femur: a case–control study☆☆☆

OBJECTIVES To compare the body mass index (BMI) of patients with fractures in the proximal extremity of the femur with the BMI of patients without any previous history of fractures. METHODS We investigated patients of both sexes, aged 65 years or over, who were admitted to Hospital Independência, Hospital Beneficência Portuguesa or ULBRA University Hospital, between December 2007 and December 2010, with histories of low-energy trauma such as falling from a standing position. These individuals were compared with patients of the same age but without any history of fracturing of the proximal extremity of the femur (n = 89), who were attended at the geriatrics outpatient clinic of the Sociedade Porto-Alegrense de Auxílio aos Necessitados (SPAAN). RESULTS The age group of the patients with fractures in the proximal extremity of the femur ranged from 65 to 96 years (mean: 77.58). The main type of fracture was trochanteric (47; 62.2%), followed by femoral neck fractures (27; 36%). Among the patients who presented on fracturing the proximal extremity of the femur, 12% had low weight, 62.7% normal weight, 24% overweight, and 1.3% obesity. Among the patients without any history of fractures, 5.6% presented low weight, 43.8% normal weight, 33.7% overweight, and 9.8% obesity. It was observed that the patients with fractures in the proximal extremity of the femur (n = 75) presented a mean BMI of 22.6, while the patients without fractures presented a mean BMI of 25.5. CONCLUSION The patients in the group with fractures were significantly taller than those in the group without fractures and presented significantly lower BMI than those in the group without fractures.