FRACTURES AND LOW AXIAL BONE-DENSITY IN PERIMENOPAUSAL WOMEN

The relationship between past fractures and current bone density (BMD) was analyzed in a population sample of 3222 women aged 48-58. BMD was determined with dual X-ray absorptiometry (DXA) at the spine and femoral neck. 702 women reported fractures. Wrist and ankle were the most common fracture sites. Fracture history increased the risk [OR (95% CI)] of low spinal BMD (of more than 1 SD below the study population mean) by 1.75 (1.41; 2.18). The sensitivity and specificity of fracture history to detect a low spinal BMD were 31 and 80%, respectively. One SD decreases of spinal and femoral BMD equalled to respective overall fracture risks (adjusted ORs) of 1.36 (1.24; 1.50) and 1.38 (1.25; 1.51). Both BMDs related more strongly to wrist fracture [1.73 (1.47; 2.05)/1.69 (1.43; 1.99)] than to all nonwrist fractures combined [1.24 (1.11; 1.37)/1.27 (1.14; 1.42)]. Ankle and rib fractures related only to spinal [1.21 (1.00; 1.46)/1.45 (1.12; 1.87)] but tibia and foot bone fractures only to femoral [2.04 (1.37; 3.04)/2.20 (1.42; 3.41)] BMD. Spinal BMD related more strongly to fractures due to falls on same level than to fractures due to all other trauma combined. Fracture history poorly screens out low perimenopausal BMD. The results suggest that pre- and perimenopausal fractures relate to low axial bone density and that the magnitude of this relation depends on the sites of fracture and densitometry as well as on the type of trauma.