Intra-individual variability in troponin T concentration in dialysis patients

PurposeHaemodialysis patients often have increased TnT concentrations in the absence of symptoms suggestive of acute coronary syndrome. To evaluate the potential usefulness of establishing patient specific baselines, we investigated intra-individual variability of TnT concentration in stable haemodialysis patients.MethodsWe measured pre-dialysis troponin T concentrations weekly for 15 weeks in 61 stable haemodialysis patients.ResultsThirty two of 61 patients had at least one result greater than the diagnostic cut-off for significant myocardial damage of 0.04 μg/L. The intra-individual variability was small; 99% of all the variance from each patient's median was ≤ 0.063 μg/L.ConclusionsIntra-individual variability in TnT concentration is small enough to merit establishment a of baseline concentration for each haemodialysis patient. This baseline is stable over at least 15 weeks; samples need be collected no more frequently than this. A change in concentration of more than 0.06 μg/L from the individual's baseline is significant.