Objectives Analysis association between high-sensitive troponin T levels and the nonischemia factors in hospitalised elderly patients without overt coronary heart disease (CHD).
Methods A total of 354 hospitalised elderly patients, aged ≥ 65 years, without overt CHD, were included in this cross-sectional study. Cardiovascular risk factors, Clinical and historical data were obtained from medical records of patients. hs-TnT, N-Terminal pro-brain natriuretic peptide (NT-proBNP), high sensitive c-reactive protein (hs-CRP), other biochemical and serum lipid profile were measured. The estimated glomerular filtration rate (eGFR) was calculated according to Chinese improved MDRD formula. Echocardiographic test, including myocardial motion, cardiac structure and function were performed. Patients were divided into three groups based on hs-TnT tertile level: low (<0.011 ng/ml ), intermediate (0.012∼0.020 ng/ml) and high (≥0.21 ng/ml).
Results The mean (± SD) age of participants was 82.31 ± 6.33 years. hs-TnT levels were 0.003ng/ml to 0.031ng/ml. Among these elderly patients, 346 subjects (97.7%) had detectable hs-TnT (≥ 0.003 ng/ml), and 202 subjects (57.1%) had hs-TnT concentrations ≥ 0.014ng/ml. Compared to the low hs-TnT group, patients in intermediate and high hs-TnT groups were older, 82.5(8.0), 83.0(7.0), 85.0(6.0) respectively, and the proportion of male were higher, 57.9%, 73.5%, 87.0% respectively. The levels of log NT-proBNP (2.28 ± 0.37 pg/dl, 2.49 ± 0.40 pg/dl, 2.82 ± 0.58 pg/dl) and uric acid (312.10 ± 93.76μmol/L, 339.88 ± 104.80μmol/L, 385.11 ± 119.29μmol/L) increased as well as the level of eGFR decreased (75.41 ± 17.56 ml•min-1•1.73m-2, 70.44 ± 17.06 ml•min-1•1.73m-2, 63.94 ± 20.62 ml•min-1•1.73m-2) in proportion to increasing tertile level. The levels of creatine kinase and CK-MB had no significant differences in three groups. Compared to the low hs-TnT group, patients in intermediate and high hs-TnT groups had increase of left ventricular end-systolic diameter (LVESD) (30.26 ± 2.41mm, 31.17 ± 3.54mm, 32.87 ± 3.71mm) and left ventricular mass index (106.65 ± 18.36, 113.81 ± 25.73, 128.33 ± 34.60). Patients in high hs-TnT group also had significant increase of left atrial diameter and left ventricular end-diastolic diameter as well as decrease of left ventricular ejection fraction compared to those in low and intermediate groups. The proportions of diabetes (32.6%, 46.0%, 53.9%), cardiac arrhythmias (17.5%, 28.3%, 38.3%), ventricular wall motion abnormalities (18.3%, 33.6%, 43.5%) and valvular lesions (35.5%, 41.6%, 59.1%) were higher in patients in intermediate and high hs-TnT groups. In multivariable linear regression analysis, the male gender, age, NT-proBNP, LVESD and eGFR were independently associated with hsTnT levels.
Conclusions The present study, most of elderly patients without CHD showed detectable hs-TnT levels, 57.1% of the subjects showed the levels ≥ 0. 014 ng /ml. hs-TnT levels were associated with male, age, diabetes, ventricular wall motion abnormality, cardiac structure and function abnormality, renal function reduction and NT-proBNP levels. Our findings suggest hs-TnT levels maybe predicate poor prognosis in elderly patients without CHD. Further prospective studies are needed to determine whether hs-TnT provides useful prognostic information in the elderly population.