3.1 Troponins and MACE at long-term follow-up.
Among the entire population, 29 patients were lost to follow-up because they refused to participate to the follow-up or did not answer to telephone calls. Follow-up data were, therefore, available in 512 patients, who were followed for a median time of 22.7 months (IQR: 7.2-43.2 months), yielding a total of 1175 patient-years of observation.
During the entire follow-up, 140 patients experienced a MACE (66 non-fatal MI, 74 cardiovascular deaths).
In the whole cohort, a multivariable COX regression analysis showed that age (HR: 1.06; 95%CI: 1.04-1.08; p value <0.001); in-hospital maximum levels of hs-cTnT (HR: 2.02; 95% CI: 1.59-2.58; p<0.001), heart failure (1.90; 95% CI: 1.23-2.95; p=0.004), and CHD (HR: 1.65; 95% C.I. 1.09-2.49; p value =0.018) independently predicted MACE, after adjusting for sex, smoking habit, COPD, arterial hypertension, CKD, diabetes, history of stroke, PAF and CAF).
To better stratify MACE risk in relation to troponin levels, in hospital maximum hs-cTnT were stratified in 5 quintiles (≤0.010 µg/L; 0.011-0.014 µg/L; 0.015-0.030 µg/l; 0.031-0.074 µg/L, >0.074 µg/L). A multivariable COX regression analysis showed age, heart failure, CHD and the increasing quintiles of hs-cTnT (HR: 2.16; 95% CI: 1.82-2.58; p value <0.001) predicted MACE, after adjusting for the possible confounding variable (Figure 1).