Incidence and risk factors for a second hip fracture in elderly women. The Study of Osteoporotic Fractures.
Women with hip fracture have an increased risk of second hip fracture but other risk factors for a second hip fracture have not been established. We sought to determine the incidence and risk factors for second hip fracture, in a prospective cohort study of community-dwelling postmenopausal women over 65 years: the Study of Osteoporotic Fractures. From a cohort of 9,704 women, 632 women with a documented first hip fracture during the study were followed up until a second hip fracture or the end of follow-up. Clinical risk factors and bone mineral density were assessed at the beginning of the study. Fifty-three second hip fractures were validated by radiographs. Women with hip fracture had a 2.3% per year risk of second hip fracture. Women who walked for exercise at baseline were less likely to sustain a second hip fracture with a relative risk (RR) of 0.5 [0.3-0.9], as were those who had normal depth perception (RR=0.5 [0.3-0.9]). Women who lost weight since age 25 years had an increased risk of second incident hip fracture (RR = 2.7 [1.6-4.6]), as did those who had a low calcaneal bone mineral density (RR=1.5 [1.1-2.0] per standard deviation decrease in bone mineral density). Current use of estrogen replacement therapy at baseline was protective (RR=0.5 [0.3-0.9]) up to 2 years of follow-up. We conclude that community-dwelling women with a first hip fracture have a high risk of second hip fracture, and risk factors for this second fracture are similar to those of first hip fracture.
Chapurlat
R D
RD
Prevention Sciences Group, University of California at San Francisco, California, USA. roland.chapurlat@laposte.net
Bauer
D C
DC
Nevitt
M
M
Stone
K
K
Cummings
S R
SR
D000368:Aged; D005260:Female; D016330:Frail Elderly; D006620:Hip Fractures / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D008019:Life Style; D015663:Osteoporosis, Postmenopausal / Q000150:complications*; D011446:Prospective Studies; D012008:Recurrence; D012307:Risk Factors; D014481:United States / Q000453:epidemiology