Subsequent fracture rates in a nationwide population-based cohort study with a 10-year perspective

Summary:
Fractures after the age of 50 are frequently observed
in Denmark, and many of these may be osteoporotic. This
study examined the incidence of all and subsequent fractures in
a 10-year period from 2001 to 2011. The incidence of subsequent
fractures was high, especially following hip fracture.
Introduction: The purpose of this study is to examine patterns
of subsequent fractures and mortality rates over a 10-year
period in patients already suffering from fracture.
Methods: The study was designed as a nationwide, registerbased
follow-up study. Patients were included if diagnosed
with an index fracture (ICD-10 codes: S22.x, S32.x, S42.x,
S52.x, S62.x, S72.x, S82.x, S92.x, T02.x, T08.x, T10.x and
T12.x) between January 1st, 2001 and December 31st, 2001
and if older than 50 years at time of fracture. The patients were
investigated for future subsequent fractures from January 1st,
2002 to December 31st, 2011.
Results: In this study, we demonstrated that patients with
fractures (especially hip fractures) have a high risk of
subsequent fractures, especially hip fracture. Other fractures,
which are not commonly considered as osteoporotic fractures,
such as lower leg, were frequently observed in the 10 years
following index fracture. The cumulative incidence proportion
(CIP) of subsequent fractures during the 10-year followup
period was high for all recurrent fractures (9–46 %). Subsequent
hip fracture, regardless of index fracture, had the
highest CIP across the study period, ranging from 9 to 40 %.
Appendicular fractures were often followed by a recurrent
fracture, or subsequent fractures at a more proximal location
in the same limb, i.e. forearm fractures were followed by
humerus fractures. These results have not been previously
demonstrated to this extent, and according to our knowledge,
no previous studies have estimated cumulative 10-year subsequent
fracture incidences for any non-hip fractures.
Conclusion: Patients suffering a fracture (and especially a hip
fracture) have a high incidence of subsequent fracture. Fractures
after the age of 50 may be considered an early warning of
increased risk for future fractures in many patients.