Author + information
- Dimitrios Farmakis, MD, PhD⁎ (, )
- Ioanna Andreadou, PhD and
- Athanasios Aessopos, MD, PhD
- ↵⁎First Department of Internal Medicine, University of Athens Medical School, Laiko Hospital, 17 Ag. Thoma Street, Athens 11527, Greece
We read with great interest the recent paper by Rubin et al. (1) on the association of hyperglycemia with subclinical myocardial injury, indicated by the correlation between glycated hemoglobin (HbA1c) and high-sensitivity cardiac troponin T (hs-cTnT), respectively.
As pointed out by the authors (1), HbA1c, in addition to being an established marker for the monitoring of medium-term glycemic status, it is now also recommended for the screening and diagnosis of diabetes mellitus (HbA1c ≥6.5%) (2). However, it should be stressed that only certain standardized HbA1c assays are suitable for diagnostic purposes and definitely none of the point-of-care ones, as stressed by the American Diabetes Association (2).
The introduction of the novel hs-cTnT assays, developed to provide a more sensitive and timely diagnosis or rule-out of acute coronary syndromes, has rendered clinicians and scientists eager for their use in daily practice and in clinical research as surrogates for several endpoints. However, before starting to use them to jump to clinically relevant conclusions, we need to clarify what a minor elevation of hs-cTnT level truly stands for, especially given the fact that the applied cutoffs have been derived by fairly healthy and relatively young populations. On this issue, the authors are to be congratulated because they seem to have made every effort to adjust for several variables and potential confounders (1). However, they also excluded individuals with advanced age or comorbidities, such as atrial fibrillation, renal dysfunction, and stroke, and therefore their findings may not be applicable to the general population.
The pathophysiology underlying the minor troponin increase and the impact of several parameters that may impair its release or clearance and therefore the values detected by the highly sensitive assays should be refined (3). The establishment of different age-, sex-, or medical history–specific cutoffs seems quite complicated, whereas some authors have developed algorithms to guide the clinical use of hs-cTnT in different patient groups. On the other hand, the clinical benefit and the cost-effectiveness of modifying our therapeutic strategies according to the results of hs-cTnT tests should also be evaluated by proper trials.
The high sensitivity of the new troponin assays enhances their clinical performance but also increases the need for better refinement of their clinical significance.
- American College of Cardiology Foundation