Effect of comorbidities and postoperative complications on mortality after hip fracture in elderly people: prospective observational cohort study.

ABSTRACT

OBJECTIVES: To evaluate postoperative medical complications and the association between these complications and mortality at 30 days and one year after surgery for hip fracture and to examine the association between preoperative comorbidity and the risk of postoperative complications and mortality. DESIGN: Prospective observational cohort study. SETTING: University teaching hospital. PARTICIPANTS: 2448 consecutive patients admitted with an acute hip fracture over a four year period. We excluded 358 patients all those aged < 60; those with periprosthetic fractures, pathological fractures, and fractures treated without surgery; and patients who died before surgery. INTERVENTIONS: Routine care for hip fractures. MAIN OUTCOME MEASURES: Postoperative complications and mortality at 30 days and one year. RESULTS: Mortality was 9.6% at 30 days and 33% at one year. The most common postoperative complications were chest infection (9%) and heart failure (5%). In patients who developed postoperative heart failure mortality was 65% at 30 days (hazard ratio 16.1, 95% confidence interval 12.2 to 21.3). Of these patients, 92% were dead by one year (11.3, 9.1 to 14.0). In patients who developed a postoperative chest infection mortality at 30 days was 43% (8.5, 6.6 to 11.1). Significant preoperative variables for increased mortality at 30 days included the presence of three or more comorbidities (2.5, 1.6 to 3.9), respiratory disease (1.8, 1.3 to 2.5), and malignancy (1.5, 1.01 to 2.3). CONCLUSIONS: In elderly people with hip fracture, the presence of three or more comorbidities is the strongest preoperative risk factor. Chest infection and heart failure are the most common postoperative complications and lead to increased mortality. These groups offer a clear target for specialist medical assessment.