A medical history of arterial thrombosis is a strong predictor of post-operative myocardial infarction and stroke in patients with hip fractures-a nationwide cohort study

INTRODUCTION: Hip fractures lead to a substantial burden of disease and mortality among the elderly. Myocardial infarction (MI) and stroke are serious and overlooked complications, and their impact on mortality and morbidity may be underestimated. We investigated; 90-day absolute risk of stroke and MI following hip fracture surgery, and ii) anamnestic risk factors associated with elevated risk of postoperative MI and stroke.

METHODS: All Danish patients aged ≥60 undergoing first time hip fracture surgery in 2000-2017 were identified. Outcomes were MI or stroke 90 days after surgery. We performed gender-stratified cumulative incidence functions and multivariate Cox regression models adjusted for age and comorbidities.

RESULTS: 124,660 patients were included. Incidence of MI was 2.2% and 1.3%, and incidence of stroke was 3.5% and 2.5%, in men and women, respectively. The most important risk factor for MI and stroke was a previous event. Hazard ratio (HR) of MI associated with previous MI was 2.43 (95% Confidence Interval (CI) 2.02-2.92) in men and 2.65 (95% CI 2.23-3.16) in women, while the HR of stroke associated with previous stroke was 4.17 (95% CI 3.73-4.67) and 3.73 (95% CI 3.43-4.08), respectively. Other risk factors of MI were; sex, age, and a history of heart failure, hypertension, peripheral artery disease or diabetes. For postoperative stroke; sex age, and atrial fibrillation were important risk factors.

CONCLUSION: MI and stroke after hip fractures are overlooked and serious complications. Persons with elevated risk can be identified at admission, based on their medical history.