Ninety-day mortality of extremely elderly patients undergoing hip fracture surgery and its association with preoperative cardiac function: a single-center retrospective study

Purpose We investigated the 90-day mortality rate in elderly patients who underwent hip fracture surgery and the association of preoperative cardiac function with mortality. Methods We retrospectively enrolled 133 consecutive patients aged 80 years or older who underwent hip fracture surgery. We obtained information for patient sex, age, comorbidities, medications, anesthesia method, left ventricular systolic and diastolic functions assessed by echocardiography, and preoperative brain natriuretic peptide (BNP) levels. Multivariate logistic regression analysis was performed. Results The 90-day mortality rate in patients with a mean age of 88.9 years was 7.5% (10/133). More than half of the patients had diastolic dysfunction of the left ventricle. There were no significant differences in preoperative cardiac systolic and diastolic functions between the mortality group and non-mortality group. The preoperative BNP level in the mortality group was significantly higher than that in the non-mortality group ( p = 0.038). Preoperative BNP level was not an independent risk factor for 90-day mortality ( p = 0.081) in the primary multivariate logistic regression analysis but was an independent risk factor ( p = 0.039) with an odds ratio of 1.004 (95% CI 1.000–1.008) in the sensitivity analysis with different explanatory variables. Conclusion The 90-day mortality rate in patients over 80 years old after hip fracture surgery was 7.5%. There were no significant differences in preoperative cardiac function assessed by echocardiography between the mortality and non-mortality groups. Our results suggest that there is no association or only a weak association of high BNP level with 90-day mortality in this age population.