Use of warfarin is associated with delay in surgery for hip fracture in older patients

Delay in surgery for hip fractures in older patients may affect mortality and the risk of delirium. Delay in surgery may occur as a result of several factors. It has not been established whether certain patient-related factors, such as a high international normalized ratio (INR) caused by warfarin treatment is associated with delay in surgery. The aim of this study was to explore the associations between warfarin treatment, INR, and time from admission to surgery.

This is an observational study based on data from a database of all hip fracture patients aged ≥ 65 years who were admitted to an orthogeriatric unit. The database included data from 1192 consecutive patients admitted from January 2007 to April 2010. Data were collected during routine work. Use of warfarin, patient characteristics, medical complications, length of stay, and time from admission to surgery were registered from the patients' records, and INR at admission in warfarin users.

Warfarin was used by 117 (9.8%) patients at admission, which included more men (n = 42; 14.4%) than women (n = 75; 8.3%) (P = 0.003). The mean age was 85 years, with no difference between users and nonusers. Warfarin users had more comorbid diseases (mean, 2.1 vs 1.8; P = 0.003), poorer health status (American Society of Anesthesiologists score of 3-5 in 77.8% vs 51.0%), and longer waiting time for surgery compared with nonusers (mean, 23 vs 12 hours; P < 0.001). There was no difference in need for blood transfusions (28.2% of users compared with 25.3% of nonusers; P = 0.49). Length of stay was longer among warfarin users compared with nonusers (mean, 14.6 vs 11.7 days; P = 0.002). Warfarin users with an INR of ≥ 2 had a longer waiting time than those with an INR of < 2, but they had a longer waiting time than nonusers.

Hip fracture patients who are using warfarin experience a longer waiting time for surgery, most likely due to more comorbidities. A more active approach to better management of comorbidities may reduce waiting time for surgery in warfarin users.