The aim of this study was to survey the incidence of osteoporotic fragility fractures, which include vertebral, hip, distal radius, and proximal humerus fractures, in patients ≥ 50 years of age, from 2004 to 2015, in Sado City, Japan. We examined temporal changes in the incidence of these fractures from 2010 through 2015. The incidence of vertebral (p < 0.001) and radius fractures (p = 0.001) was lower in 2015 than in 2010, with only the incidence of hip fracture (p = 0.013) being lower in 2015 than in 2004. With regard to age-specific incidences, there was a sharp increase in vertebral and hip fractures among the segment of the population 70-89 years old, with no remarkable change in the incidence of radial and humeral fractures. Pre-existing vertebral fractures were identified in 69.6% of patients with a hip fracture, 35.6% of patients with a distal radius fracture, and 55% of patients with a humeral fracture. Among patients with pre-existing vertebral fractures, 42.5% had a single fracture, whereas 57.5% had 2 or more fractures. The proportion of patients on anti-osteoporotic agents before the occurrence of fractures increased to 14.5% in 2015, compared to 4% in 2004 and 7.6% in 2010. We speculate that the increase in the use of anti-osteoporotic agents is the main reason for the declining incidence of fractures. Therefore, considering the sharp increase in hip and vertebral fractures among individuals in their mid-1970s and older, judicious use of anti-osteoporotic agents among these individuals could be useful for lowering the occurrence of these fractures.
Keywords: Distal radius fracture; Hip fracture; Humerus fracture; Incidence; Vertebral fracture.