Objectives Cardiac troponins are specific for the heart, but not for the acute coronary syndrome. We wanted to assess how common elevated cardiac troponin concentrations were, in a population with significant non-cardiac disease. Design Methods We measured both hs-cTnT and hs-cTnI on all samples submitted to the laboratory during one 24 h period, and assessed the magnitude of the cTn concentration with the location and severity of disease of the patient. Results Community patients and patients from the maternity ward had the lowest cTn concentrations with results above the 99th percentile being only 0–2% of the total. As expected, the highest proportion of results > 99th percentile came from Coronary Care and Intensive Care. However, substantial numbers of persons on Medical and Surgical wards, without a primary diagnosis of cardiac disease, also had cTn > 99th percentile. Particularly for cTnT, there was a highly significant odds ratio predicting mortality when results above and below the 99th percentile were compared. Conclusions Significant illnesses apart from the acute coronary syndrome are important causes of a rise in cTn to above the 99th percentile, and appear to reflect the total body burden of disease. Even when the high hs-cTn concentration is not due to the acute coronary syndrome, there is a significant association with all-cause mortality.