The Correlation between Lower Extremity Fracture and Subsequent Arterial Embolism and Thrombosis-A National Population Cohort Study

Abstract

The hazard of subsequent arterial embolism and thrombosis (SAET) in patients with lower leg fractures is not yet well demonstrated. The purpose of this study is to determine the correlation between lower leg fracture and SAET in Taiwan. A total of 134,844 patients with lower leg fractures (ICD-9-CM: 823) and chronological diagnosis as SAET (ICD-9-CM: 444.22) was matched (1:1) to the non-fracture cohort according to their propensity score (data coming from the National Health Insurance database between January 2000 to December 2012). Patients were matched by age, gender, and comorbidities. The incidence of SAET and correlation between SAET development and lower leg fracture was statistically analyzed, and subgroup analysis categorized by characteristics and comorbidities was conducted as well. The cumulative incidence of SAET was calculated by Kaplan-Meier analysis. Kaplan-Meier analysis plot showed that, by the end of the ten-year follow-up period, the cumulative incidence of SAET was significantly higher for the lower leg fracture cohort than for the non-fracture cohort (log-rank test: p < 0.001). The lower leg fracture, male, elder age (45-64-year-old; ≥65-year-old), hypertension, diabetes mellitus, and gout were significantly associated with lower extremity SAET risk compared with the matched group. There was an inseparable correlation between the lower leg fracture group and the risks of SAET; subgroup analysis by gender (male, female), age (age < 40 years, age 40-64 years, and age > 65 years) and comorbidities (hypertension, diabetes mellitus, and gout) show compatible results as well. Patients with lower leg fracture have a significantly increased risk of SAET since then two years after the fracture. The hazard of SAET was significantly higher in patients with lower leg fracture than in the non-fracture cohort, and the high incidence was found since then two years after fracture. Further studies are warranted.

Keywords: arterial embolism and thrombosis; lower leg fractures.

Figure 1

Kaplan–Meier analysis plot showed that, by the end of the ten-year follow-up period, the cumulative incidence of PAOD was significantly higher for the lower leg fracture cohort than for the non-fracture cohort (log-rank test: p < 0.001).