Hip fracture predicts subsequent hip fracture: a retrospective observational study to support a call to early hip fracture prevention efforts in post-fracture patients

Abstract

In this real-world retrospective cohort, subsequent hip fracture occurred in one in four patients with any initial fracture, most often after hip fracture, on average within 1.5 years. These data support the need for early post-fracture interventions to help reduce imminent hip fracture risk and high societal and humanistic costs.

Purpose: This large retrospective cohort study aimed to provide hip fracture data, in the context of other fractures, to help inform efforts related to hip fracture prevention focusing on post-fracture patients.

Methods: A cohort of 115,776 patients (72.3% female) aged > 65 (median age 81) with an index fracture occurring at skeletal sites related to age-related bone loss between January 1, 2011, and March 31, 2015, was identified using health services data from Ontario, Canada, and followed until March 31, 2017.

Results: Hip fracture was the most common second fracture (27.8%), occurring in ≥ 19% of cases after each index fracture site and most frequently (33.0%) after hip index fracture. Median time to a second fracture of the hip was ~ 1.5 years post-index event. Patients with index hip fracture contributed the most to fracture-related initial surgeries (64.1%) and post-surgery complications (71.9%) and had the second-highest total mean healthcare cost per patient in the first year after index fracture ($62,793 ± 44,438). One-year mortality (any cause) after index hip fracture was 26.2% vs. 15.9% in the entire cohort, and 25.9% after second hip fracture.

Conclusion: A second fracture at the hip was observed in one in four patients after any index fracture and in one in three patients with an index hip fracture, on average within 1.5 years. Index hip fracture was associated with high mortality and post-surgery complication rates and healthcare costs relative to other fractures. These data support focusing on early hip fracture prevention efforts in post-fracture patients.

Keywords: Healthcare resource utilization; Hip fracture; Imminent risk; Mortality; Osteoporosis; Real-world data.

Fig. 1

Flow diagram of patients included in the cohort. ^aAll patients with a valid IKN with a fracture occurring at an osteoporotic fracture site (hip, vertebral [clinical], wrist [distal radius, or both distal radius and ulna], clavicle/ribs/sternum, humerus, tibia/fibula/knee [including medial and lateral malleolus], pelvis, radius/ulna [proximal, midshaft or distal ulna only], multisite, femur) between January 1, 2011, and March 31, 2015. Fractures were identified using ICD-10-CA codes from hospital admissions, emergency room visits and ambulatory care. ICD-10-CA International Classification of Diseases, 10th revision, Canada, IKN ICES key number

Fig. 2

Second fracture of the hip based on index fracture site. A Distribution of second fracture based on index fracture site. ^aThe most common second fracture site for a given index fracture. ^bPercentages based on total number of patients with an index fracture occurring at a given site. Values at the top of each bar represent % (number) of second fracture of any site. ^cIndex fracture occurring at major osteoporotic fracture site. B Median time to second hip fracture based on index fracture site. ^aPercentages based on the total number of second fractures in a given index fracture site. IQR interquartile range

Fig. 3

Contribution of index hip fractures to the total number of patients undergoing initial surgery, experiencing complications or to 1-year mortality. ^aPercentages based on the number of patients who experienced ≥ 1 post-surgery complication within 30 days