Impact of troponin 1 on long-term mortality after emergency orthopaedic surgery in older patients.

OBJECTIVES: To determine the association between post-operative troponin rises and longer term (2-year) mortality after emergency orthopaedic surgery in patients over 60 years of age.

METHODS: One hundred and two patients were recruited in 2006 and had inpatient troponin 1 measurements. These patients were followed up by a telephone call annually for complications.

RESULTS: At 2 years, 29.4% (30/102) of patients had died. Twenty-five patients (25/54 or 49.3%) with a troponin rise were dead at 2 years compared with five patients without a troponin rise (5/48 or 10.4%), which was significantly different P < 0.0001. Patients with a higher troponin level (>0.1 µg/L) were more likely to be dead at 2 years compared with those with a lower level of troponin. However, when adjusted for other comorbidities the association between troponin elevation and death at 2 years did not persist. Using Cox regression multivariate analysis, only one factor, sustaining an in-hospital cardiac event odds ratio 4.3 (95% confidence interval 1.8-10.3, P = 0.001), was associated with 2 years all-cause mortality . Furthermore, patients who sustained a symptomatic troponin rise (P < 0.0001) or asymptomatic troponin rise (P = 0.004) were more likely to have died at 2 years compared with those with no troponin rise. Three factors were significantly associated with a cardiac event during the second year: (i) post-operative troponin rise (P = 0.05); (ii) pre-morbid atrial fibrillation (P = 0.04); and (iii) post-operative renal failure (P < 0.001).

CONCLUSION: Elevated post-operative troponin levels are predictive of 1-year but not 2-year mortality in older patients undergoing emergency orthopaedic surgery.