Myocardial infarction after hip fracture repair: a population-based study

Objectives: To quantify the occurrence of myocardial infarction (MI) occurring in the early postoperative period after surgical hip fracture repair and estimate the effect on 1-year mortality.

Design: A population-based, historical cohort study of individuals who underwent surgical repair of a hip fracture that used the computerized medical record linkage system of the Rochester Epidemiology Project.

Setting: Academic and community hospitals, outpatient offices, and nursing homes in Olmsted County, Minnesota.

Participants: Over the 15-year study period (1988-2002), 1,116 elderly adults underwent surgical repair of a hip fracture.

Measurements: At the end of the first 7 days after hip fracture repair, participants were classified into one of three groups: clinically verified MI (cv-MI), subclinical myocardial ischemia, and no myocardial ischemia. One-year mortality was compared between these groups. Multivariate models assessed risk factors for early postoperative cv-MI and 1-year mortality.

Results: Within the first 7 days after hip fracture repair, 116 (10.4%) participants experienced cv-MI and 41 (3.7%) subclinical myocardial ischemia. Overall 1-year mortality was 22%, with no difference between those with subclinical myocardial ischemia and those with no myocardial ischemia. One-year mortality for those with cv-MI (35.8%) was significantly higher than for the other two groups. Occurrence of early postoperative cv-MI, male sex, and history of heart failure or dementia were independently associated with greater 1-year mortality, whereas prefracture home residence and preoperative higher hemoglobin were protective.

Conclusion: Rates of early postoperative, cv-MI after hip fracture repair exceed rates after other major orthopedic surgeries and are independently associated with greater 1-year mortality.