Stable high-sensitivity cardiac troponin T levels and the association with frailty and prognosis in patients with chest pain

•Chronic myocardial injury, defined as stable high-sensitivity cardiac troponin > 99th percentile value, is associated with frailty.•Clinicians should acknowledge patients with chronic myocardial injury who also are frail, as these factors are strongly associated with a worse prognosis.•Chronic myocardial injury could be a marker of a biologically aged heart and may in the future be used to identify prematurely aged individuals who could benefit from early prevention strategies. Chronic myocardial injury is defined by stable high-sensitivity cardiac troponin (hs-cTn) levels above the 99th percentile value, which may be a sign of a biologically aged heart. This study investigated the association between frailty and chronic myocardial injury. In a cohort of patients with chest pain and stable hs-cTnT levels measured 2011–2014, we included all patients who were assessed by two scoring systems measuring frailty. Adjusted odds ratios (ORs) were calculated to estimate the risk of frailty at different hs-cTnT levels (referent: hs-cTnT ≤ 14 ng/l). Cox regression was used to estimate risks of death and cardiovascular events in relation to frailty status and hs-cTnT levels (referent: non-frail and hs-cTnT ≤ 14 ng/l). A total of 979 patients were included, of whom 269 (27%) had chronic myocardial injury. The risk of being frail was almost four times higher in patients with chronic myocardial injury, compared with patients in the reference group (hs-cTnT ≥ 30 ng/l: OR: 3.69, 95% CI: 2.02-6.76). During a follow-up of 4.3 years, 275 (28%) patients died. Mortality risks increased with increasing hs-cTnT levels and degree of frailty, being increased four-fold in frail patients with hs-cTnT levels ≥ 30 ng/l (HR: 4.07, 95% CI: 2.42-6.86). Stable hs-cTnT levels are associated with the degree of frailty, and frailty measurements could help to identify patients with stable hs-cTnT levels who are at a high risk of death. The findings support the hypothesis that chronic myocardial injury could be a marker of a biologically aged heart.