Purpose: Atrial fibrillation (AF) has been associated with elevated levels of cardiac troponins; however, it is not clear if this association is independent of underlying cardiovascular disease. The aim of this study was to investigate the impact of AF on cardiac troponin I levels in a 75-year-old cohort from the general population, using a recently introduced, highly sensitive assay.
Methods: All 75-year-old citizens in Asker and Baerum counties were invited to participate in a prevalence study of AF. High-sensitive troponin I (hs-TnI) levels were measured (Abbott Diagnostics) in serum samples collected from 62 subjects with AF and a gender-matched control group of 126 subjects in sinus rhythm.
Results: Hs-TnI was detectable in all subjects (median 7.3 ng/L [range 3.0-88.7]). Patients with AF had higher levels than subjects in sinus rhythm (8.3 ng/L [3.7-88.7] vs. 6.8 ng/L [3.0-77.5]; p = 0.011). Male gender (p = 0.002), hypertension (p = 0.001), coronary heart disease (p < 0.001), heart failure (p < 0.001), prior stroke or transient ischemic attack (p = 0.013) and serum creatinine (p < 0.001) were all associated with higher levels of hs-TnI in univariate analysis. Heart failure and coronary heart disease remained significantly associated with hs-TnI in multivariate analysis, whereas the relation between AF and hs-TnI was no longer statistically significant.
Conclusion: All subjects had detectable levels of hs-TnI. AF patients had higher hs-TnI levels than subjects in sinus rhythm; however, this difference was not statistically significant after adjustment for heart failure and coronary heart disease.
Keywords: Biomarkers; cardiac arrhythmia; cardiology; cardiovascular diseases; cohort studies; immunoassays.