First-ever stroke following hip replacement surgeries: a large population-based survey.

Objective: This study was designed to determine the prevalence, subtypes and risk factors of first-ever stroke following hip replacement (HR) in a large population of Taiwan.

Methods: Using the National Health Insurance system of Taiwan, we identified patients undergoing HR from 2000 to 2011 and randomly selected 4 : 1 age- and sex-matched controls for each HR patients. The index date for HR patients was defined the date for HR. All study subjects were followed from the index date until stroke occurred at admission. T-test and chi-square test were used for continuous and categorical variables, respectively. The hazard ratios of risk factors were determined with Cox proportional hazard regression model.

Results: A total of 3604 HR patients and 14 394 controls were enrolled. In comparison with controls, patients undergoing HR had a significantly higher incidence of comorbidities (i.e. atrial fibrillation, hypertension, diabetes) and consumed more medications (i.e. antihypertension, antidiabetes, nonsteroid anti-inflammatory drugs and anticoagulants) before surgery. The HR patients had a significant higher incidence of first-ever stroke, especially for those aged over 65. (Hazard ratio: 1·33, 95% confidence interval: 1·12-1·58) The significantly higher risk for first-ever stroke occurred within 3 months and ≥ 1 year after HR. The incidence rate of ischaemic stroke is about five times than that of haemorrhagic stroke.

Conclusion: Our study identifies multiple risk factors that cause cerebrovascular complications after HR, which is vital in creating treatment plans to prevent for said problems.