Radial and humeral fractures as predictors of subsequent hip, radial or humeral fractures in women, and their seasonal variation

Abstract

Hip fractures are common in elderly women, and early risk assessment of future hip fractures is relevant in relation to prevention. We studied the predictive value of radial and humeral fractures in women. The influence of weather conditions on the risk was also studied. Women aged 20–99 years with a fracture of the distal radius (n=1162) or proximal humerus (n=406) were followed for 0 to 9 years. The relative risk (RR) and 95% confidence limits (CL) of subsequent fracture among women suffering radial or humeral fractures compared with the background population were calculated. Women 60–79 years of age who had suffered a fracture of the distal radius or proximal humerus had relative risks of sustaining a hip fracture of 1.9 (1.3–2.6, 95% CL) and 2.5 (1.3–3.6, 95% CL) respectively. The relative risk of hip fracture was highest within the first years following a fracture of the radius or the humerus. Women suffering an upper extremity fracture (radius or humerus) in snowy or icy weather had a marginally increased risk (RR=1.3, 0.4–2.3, 95% CL and RR=1.8, 0.3–3.4, 95% CL) for a later hip fracture. A woman 50 years old with a radial or a humeral fracture had an estimated residual lifetime risk of sustaining a subsequent hip fracture of 17% and 16% respectively compared with 11% for the background population. The moderately increased risk of hip fractures in peri- and postmenopausal women suffering upper extremity fractures may be caused by a greater propensity to fall and/or be related to a higher degree of osteoporosis compared with the background population. For individuals other indicators of hip fracture should also be considered to improve the risk estimation of a later hip fracture.