Mortality Risk After Atypical Femoral Fracture: A Systematic Review and Meta-analysis

To summarize all available data using systematic review and meta-analysis to estimate the 1-year mortality risk after atypical femoral fracture (AFF) and risk ratio of mortality after AFF versus typical femoral fracture (TFF). Potentially eligible studies were identified from MEDLINE and Embase databases from inception to February 2022 using a search strategy that comprised the terms for “atypical femoral fracture” and “mortality.” An eligible study must consist of a cohort of patients with AFF. Then, the study must report the 1-year mortality rate after the AFF or report effect estimates with 95% confidence intervals, comparing the incident mortality between patients with AFF and TFF. Point estimates with standard errors were retrieved from each study and combined using the generic inverse variance method. A total of 8967 articles were identified. After 2 rounds of independent review by 3 investigators, we identified 7 studies reporting the 1-year mortality rate of AFFs and 3 studies comparing the mortality rate of AFF with that of TFF. Pooled analysis revealed a pooled 1-year mortality rate after an AFF of 0.10 (95% confidence interval, 0.05-0.16; I2 = 93.3%). Two studies compared the mortality risks of AFF with those of TFF and revealed conflicting results. The 1-year mortality rate after an AFF was approximately 10%. However, evidence is insufficient to conclude whether there was a difference in mortality risk between AFF and TFF.