TNNI3 and hippocampal atrophy: People with cardiac troponin I concentrations >5.2 ng/L had 0.63% (95%CI: 0.23 to 1.04%) lower grey matter volume and 18% (95%CI: 0 to 40%) increased risk of hippocampal atrophy compared with those with cardiac troponin I <2.5 ng/L, corresponding to an age effect of 2.7 and 3 years, respectively (Table 4).