HIP-FRACTURES, RISK-FACTORS, BONE-MINERAL DENSITY, BODY-COMPOSITION AND BIOCHEMICAL-CHANGES IN PATIENTS AND AGE-MATCHED CONTROLS

During one year (6/93 - 5/94) we performed a prospective study in pati ents with hip fracture, treated at the Hospital de Clinicas. A total o f 102 women 52 to 94 years of age (Mean +/- ISD: 79.5 +/- 9.1 years) a nd 17 men 61 to 98 years of age (79.7 +/- 9.9 years) who had sustained a hip fracture due to mild or moderate trauma were included. The rati o women: men was 6:1. We also studied 55 age-matched control women wit hout diseases that could affect the skeleton or previous hip fracture (77.1 +/- 5.8 years of age). We did not study a control group in men. Women with hip fractures had lower weight (p < 0.01), lower age of ons et of the menopause (p < 0.01) and a tendency to have with a greater f requency a mother with hip fracture (p < 0.08) compared with age-match ed controls. When vertebral fractures were excluded, 44% of the hip fr acture women had sustained previous skeletal fractures, while only 16% of the age-matched controls had suffered previous skeletal fractures (p < 0.001) (Table 2). The most frequent previous skeletal fractures w ere wrist and humerus. Forty eight percent of hip fracture women had h ad at least one vertebral fracture. About 17% of the hip fractured men had sustained previous skeletal fractures, while 5/12 men had suffere d at least one vertebral fracture. Hip fractured women and men sustain ed greater history of diseases which provoke postural instability (Tab le 3). Biochemical determinations showed significantly diminished leve ls of serum albumin (p < 0.001) and calcium (p < 0.01), and increased serum PTH (p < 0.05) compared to age-matched controls (Table 4), Bone mineral density (determined by dual energy X-ray absorptiometry) was s ignificantly diminished over proximal femur, total skeleton, legs and pelvis (p < 0.001), head and spine (p < 0.05) (Table 5). Body composit ion measurements showed that hip fracture women had a significantly lo wer lean mass compared with controls (p < 0.05), Fat mass also was low er in fracture patients compared with controls, but the difference was not statistically significant (Table 5). We conclude that hip fractur e in our population is related to several previous factors: earlier on set of menopause, lower nutrition and body weight, previous diseases t hat increase the likelihood of falling, increased levels of PTH and re duced bone mass. Prevention of hip fractures should take into account all these factors, specially those that could be modified.