Haemoglobin predicts length of hospital stay after hip fracture surgery in older patients

Objectives: Treating anaemia in older patients who have undergone hip fracture surgery is to enhance functional recovery. The relationship between peri-operative haemoglobin levels and outcome after hip fracture surgery are controversial. We assessed whether higher haemoglobin levels predict length of hospital stay after hip fracture surgery in elderly subjects. Study design: A follow-up study in a historical cohort was performed in 317 patients aged 65 years old undergoing hip fracture surgery over the period 2004-2006 at the Leiden University Medical Centre. Mean outcome measures: Linear regression analysis was used to assess the association between pre- and post-operative haemoglobin level and length of hospital stay after controlling for age and sex. Results: Anaemia after hip fracture surgery was present among 86% of the patients. Length of hospital stay after hip fracture surgery in elderly subjects with post-operative anaemia (10.7 days) was significantly longer than in elderly subjects without post-operative anaemia (7.5 days, p = 0.007). Post-operative haemoglobin levels and length of hospital stay were inversely related (p = 0.013). The length of hospital stay was not related with pre-operative haemoglobin level. Conclusion: Higher postoperative haemoglobin levels predict shorter length of hospital stay after hip fracture surgery in the elderly. A definitive randomized clinical trial has to demonstrate whether this association is causal.