CAT and type 1 diabetes mellitus: Glycated haemoglobin was 6,14 ± 1,11; 95% CI: 6,06–6,57 in T1DM and 6,50 ± 0,85; 95%CI: 6,32–7,25 in T2DM, both in AA genotype of CAT and 6,19 ± 1,32, 95% CI: 6,09–6,60 in T1DM and 6,61 ± 0,54; 95%CI: 6,45–7,05 in T2DM, both in TT genotype of CAT gene, with p = 0,249.