POSSUM predicts hospital mortality and long-term survival in patients with hip fractures

Each year, some 18,000 Dutch residents, most of them elderly, suffer a hip fracture. These patients constitute a major, and increasing, healthcare problem with high mortality. In an ageing population, not only the incidence of hip fractures will increase but also comorbidity. Comorbidity is a major cause of high mortality. The physiologic and operative severity score for the enumeration of mortality and morbidity (POSSUM) system predicts mortality and morbidity in surgical patients using physiologic and operative factors.

For 272 consecutive patients who were treated in our hospital for hip fractures, all complications were registered, and orthopedic POSSUM was performed. Total survival was registered with a mean follow-up of 58 months. Discriminating performance of POSSUM was estimated using receiver-operating curves. After validation, patients were divided into three equal large groups, termed low-risk group, intermediate-risk group, and high-risk group. Kaplan-Meier survival curves were made of each group.

Orthopedic POSSUM performed well in predicting mortality with an area under the curve of 0.83 (95% confidence interval 0.76-0.89) and morbidity with an area under the curve of 0.83 (95% confidence interval 0.76-0.90). Three groups that composed of 92 (low risk), 93 (intermediate risk), and 87 (high risk) patients differed significantly in inhospital mortality, all complications, severe complications, and total survival.

This study has shown that the orthopedic POSSUM is an excellent predictor of inhospital mortality and long-term survival in patients suffering from hip fractures. It is a reasonable predictor of severe postoperative complications. The orthopedic POSSUM is a useful risk stratification and audit tool.