Mortality following atypical femoral fractures in men

Atypical femoral fractures (AFFs) are an uncommon complication of bisphosphonate (BP) treatment for osteoporosis. The purpose of this report was to determine differences in mortality among men treated with BPs who experienced AFFs, hip fractures, or typical subtrochanteric/femoral shaft (ST/FS) fractures. We included men from the Veterans Affairs Corporate Data Warehouse who filled at least one BP prescription over a nearly 20-yr span (October 1, 1999, to December 31, 2022). Typical ST/FS and hip fractures after a first filled prescription for a BP were identified using ICD codes. Radiographic review was conducted for ST/FS fractures to determine which were AFFs using the American Society of Bone and Mineral Research 2014 criterion. Demographic and clinical characteristics and cumulative duration of BP exposure prior to the incident fracture were determined. There were 23 men with an AFF, 4591 with a hip fracture, and 225 with a (non-AFF) ST/FS fracture. At 12-mo post-fracture, 4% of men with an AFF had died, compared with 25% of men with a hip fracture and 15% of men with an ST/FS fracture. Over 5 yrs. of follow-up, mortality following fracture differed among the 3 different fracture groups (χ2 = 6.21, d.f. = 2, p = .045) with death occurring in 7 of 23 (30%) men with an AFF, 2380 of 4591 (52%) men with a hip fracture and 109 of 225 (48%) men with a ST/FS fracture. In Cox proportional hazard models, over 5 yrs, with and without adjustment for covariates, there were no significant differences in mortality following an AFF compared with a hip fracture or an AFF compared with a ST/FS fracture (p > .10 for all). It is possible that mortality is lower following AFF compared with a hip or ST/FS fracture; however, limited sample size among those with AFF may have precluded ascertainment of such a difference.