Can troponin I measurement predict coronary artery calcification score in asymptomatic type 2 diabetic patients?

Abstract

Coronary artery calcification score (CACs) has been shown to be useful for assessment of cardiovascular risk in diabetic patients without known coronary artery disease. CACs score can be useful to detect high risk patients (CACs > 400) or low risk patients (CACs < 10). Troponin is known to be a biomarker of mortality and cardiovascular events in the overall population. It has been shown that troponin can be found elevated in diabetic patients without any acute coronary syndrome. The objective was to study the relationship between CAC score and troponin level in asymptomatic type 2 diabetic patients. A CACs was prospectively performed in 460 consecutive asymptomatic type 2 diabetic patients with ≥ 2 additional risk factors (age > 50 for men and > 60 for women, hypertension, current smoking, elevated LDL and albuminuria) but without any known coronary artery disease during a yearly check-up between January 2015 and December 2016. A measurement of Troponin I was systematically performed (hs-cTnI, Architect, ng/l). Mean age was 61 ± 10 [30–87] y.o. and 58% were male. Mean duration of diabetes was 15 ± 10 y and 35% were treated with insulin. Mean CACs was 287 ± 30 [0–5983]. Median hs-cTnI was 3 ng/l [0±182]. Twenty-two percent of the patients had a troponin < 2 ng/l, 83% < 5 ng/l. A significant correlation was found between CACs and hs-cTnI ( r = 0.20, P = 0.0001). hs-cTroponin I levels according to CACs are presented in Table 1 . Mean hs-cTnI was significantly lower in patients with CAC score ≤ 10 compared to CAC score > 10. No difference was found in hs-cTnI level in patients with CACs > 400 or CACs < 400. ROC curve analysis demonstrated that a threshold ≤ 3 ng/l can predict a CACs < 10 with sensitivity of 87% but a very low specificity of 34%. A threshold > 6 ng/l can predict a CACs > 400 with a very low sensitivity of 21% and specificity of 91% ( Table 1 ). The link between CACs and hs-cTnI is weak and cannot help to stratify patients with low or high CACs.