Risk factors for incident vertebral fractures in men and women: the Rotterdam Study

Abstract

Low BMD and prevalent vertebral fractures are known risk factors for incident vertebral fractures. In 3001 men and women from the Rotterdam Study, prevalent nonvertebral fractures, early menopause, current smoking, and walking aid use were also strong risk factors for incident vertebral fractures.

Introduction: Thus far, age, low BMD, and prevalent vertebral fractures are the only well-known risk factors for incident vertebral fractures. Therefore, our aim was to investigate other potential risk factors for incident vertebral fractures in the elderly.

Materials and methods: This study was based on the Rotterdam Study, a large prospective population-based cohort study among men and women > or =55 years of age. For 3001 subjects, spinal radiographs were obtained at baseline and again approximately 6.3 years later. These follow-up radiographs were scored for vertebral fractures using the McCloskey-Kanis method. Whenever a vertebral fracture was detected, the radiograph was compared with the baseline radiograph. If this fracture was not already present at baseline, it was considered incident. At baseline, information on potential risk factors was obtained.

Results: Low BMD and prevalent vertebral fractures were strong risk factors for incident vertebral fractures in both men and women (RR 2.3 [1.6-3.3] and 2.2 [0.9-5.0] for men and RR 2.1 [1.6-2.6] and 4.1 [2.5-6.7] for women, respectively). For women, age, early menopause (< or =45 years of age; RR 1.0 [1.1-3.5]), current smoking (2.1 [1.2-3.5]), and walking aid use (2.5 [1.1-5.5]) were additional independent risk factors. For men, only a history of nonvertebral fractures was a significant independent risk factor (OR 2.4 [1.2-4.8]).

Conclusion: Apart from low BMD and prevalent vertebral fractures, prevalent nonvertebral fractures are associated with an increased incident vertebral fracture risk in men. In women, early menopause, current smoking, and walking aid use are additional independent risk factors for incident vertebral fractures.