Determinants and prognostic implications of cardiac troponin T measured by a sensitive assay in type 2 diabetes mellitus.
BACKGROUND
The cardiac troponins are biomarkers used for diagnosis of myocardial injury. They are also powerful prognostic markers in many diseases and settings. Recently introduced high-sensitivity assays indicate that chronic cardiac troponin elevations are common in response to cardiovascular (CV) morbidity. Type 2 diabetes mellitus (T2DM) confers a high risk of CV disease, but little is known about chronic cardiac troponin elevations in diabetic subjects. Accordingly, we aimed to understand the prevalence, determinants, and prognostic implications of cardiac troponin T (cTnT) elevations measured with a high-sensitivity assay in patients with T2DM.


METHODS
cTnT was measured in stored, frozen serum samples from 124 subjects enrolled in the Asker and Bærum Cardiovascular Diabetes trial at baseline and at 2-year follow-up, if available (96 samples available). Results were analyzed in relation to baseline variables, hospitalizations, and group assignment (multifactorial intensive versus conventional diabetes care for lowering CV risk).


RESULTS
One-hundred thirteen (90%) had detectable cTnT at baseline and of those, 22 (18% of the total population) subjects had values above the 99th percentile for healthy controls (13.5 ng/L). Levels at baseline were associated with conventional CV risk factors (age, renal function, gender). There was a strong correlation between cTnT levels at the two time-points (r=0.92, p>0.001). Risk for hospitalizations during follow-up increased step-wise by quartiles of hscTnT measured at baseline (p=0.058).


CONCLUSIONS
Elevations of cTnT above the 99th percentile measured by a highly sensitive assay were encountered frequently in a population of T2DM patients. cTnT levels appeared to be stable over time and associated with conventional CV risk factors. Although a clear trend was present, no statistically robust associations with adverse outcomes could be found.
Hallén
Jonas
J
Department of Cardiology, Oslo University Hospital, Faculty of Medicine, University of Oslo, Oslo, Norway. jonashallen@gmail.com
Johansen
Odd Erik
OE
Birkeland
Kåre I
KI
Gullestad
Lars
L
Aakhus
Svend
S
Endresen
Knut
K
Tjora
Solve
S
Jaffe
Allan S
AS
Atar
Dan
D
D000328:Adult; D015415:Biomarkers / Q000097:blood*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology* / Q000628:therapy; D004563:Electrochemistry / Q000379:methods; D005500:Follow-Up Studies; D006331:Heart Diseases / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008163:Luminescent Measurements / Q000379:methods; D015995:Prevalence; D011379:Prognosis; D016032:Randomized Controlled Trials as Topic / Q000706:statistics & numerical data; D012307:Risk Factors; D012680:Sensitivity and Specificity; D020107:Troponin T / Q000032:analysis / Q000097:blood*
D015415:Biomarkers; D020107:Troponin T